Poll: Would You Choose Custom Geometry If You Could?

Mar 3, 2022 at 20:03
by Henry Quinney  
The Grim Donut

We've all thought it, or maybe even said it - "Why didn't they just do this?" Maybe it was an extra 5mm of reach or a degree on the head tube angle on your favorite enduro bike, either way, it's very easy to second-guess bike brands and specific geometry figures. In fact, I say this as somebody who does it in a professional capacity as I shoot my shots from the sidelines, safe in the knowledge that I won't have to ever make a bike myself and let the smart-alecs tear it apart.

The Grim Donut
"Mommy, why do my hands hurt?"

Of course, geometry is very complicated, and there might just be a very good reason your XC race bike doesn't have a 90-degree seat tube angle. Riding a bike complicates things because not only does it factor in our height and stature but it also has to consider them both as we ride our bikes in two very different positions - seated and standing. Other categories of bikes don't have to factor this in so much, and I suppose that's one of the reasons mountain-bike-specific geometry dimensions are relatively recent compared to something like top or seat tube length, which is far more prominent in something like road bikes.

The Grim Donut
Mike Levy does know best... apparently.

Trying to boil down all that into three or four sizes to suit the whole variety of humans that want to ride it is no easy task, especially considering bikes are so expensive now. Truthfully, if I was to spend thousands of dollars on a bike then I'd be pretty frustrated if I struggled to find one that actually fit properly.

There is also the added complication of how much we lean our mountain bikes. A simple geometry dimension like head angle or stack becomes a lot more complicated when off the y-axis. That's not even mentioning something like fork offset and trail or effective top tube length on the new wave of bikes with longer reaches and steeper seat tube angles.

Then again, look at the Grim Donut. After a test ride, and merely 5 brown envelopes stuffed with Tim Horton's vouchers, Yoann Barelli said he was very impressed with how it rode - and the clock backed it up.

So for this week's poll I want to know - could you design your own bike, and how accurately do you know your preferred geometry? I'm not talking about producing it but rather sending off your dimensions to a fabricator and them returning the bike to you. And, if so, what do you think it would ride like?

Would you choose you own custom bike geometry if you could?



Would a your custom geometry bike be any good?




218 Comments

  • 219 0
 80° head angle, 90° seat angle, 500mm chainstays, short reach, 26 inch in the front, 29 inch in the back, minimal stack. Everything for the perfect Upduro
  • 31 2
 You laugh, but I keep thinking putting a 26" wheel on the front of a regular XC bike would make a good goofy bike for hill climbs. The dirt bikers have fun with hill climb bikes, why not us?
  • 207 4
 @Glenngineer: because climbing with a wide open throttle is shit loads of fun, having your heart exploding after 10 pedal strokes isn't.
  • 19 12
 @Glenngineer: For most of us, climbing is a means to an end. And we don’t have a throttle.
  • 19 1
 Really could anyone take this joke seriously and just build it and test it for the sake of click baits?
  • 50 1
 time for PB to release the successor to the Grim Donut based on your geometry.

...the ...Amiable Bagel?
  • 9 0
 @Balgaroth: different thrills for different skills.
  • 20 0
 I‘m already perfect, thank you very much
  • 13 1
 @Upduro: You already have 29 inches in your rear??? Doesn't sound fun
  • 14 1
 @bashhard: front AND rear
  • 1 0
 @PauRexs: marinobike.com - could probably make your money back on YouTube if you filmed it well enough.
  • 2 0
 I will take the GDv2 any day of the week. I would use it as my downcountry bike.
  • 2 0
 @robokfc: were gravel should evolve...
  • 2 0
 Pretty close to some Walmart bikes
  • 2 0
 @Glenngineer: Because dirt bikes have motors.
  • 1 0
 @Glenngineer: You don't need to go in that direction. A steep seat angle, a long reach, long chainstays and decent bb height coupled with a 22 tooth chainring and a 52 tooth cog and you'll be ready to climb walls!
  • 1 0
 @bashhard: or… very fun?
  • 1 0
 Is that even a bike?
  • 3 0
 Here you are @bashhard !
I made sure there was room for water bottles, just in case.

a href="https://www.pinkbike.com/photo/22213978/">Bashhard Upduro/a>
  • 1 0
 @Upduro: That sounds like the same 49 inches then.
  • 150 0
 I'd like to just change 2-4 things from an existing great platform. Not reconstruct an entire bicycle.
  • 14 0
 This is where I'm at. A Medium frame with 465 reach and ~615 stack and they can fill in the blanks everywhere else on what they think works best.
  • 6 2
 Exactly. You may not know everything, but you may know a few things you prefer. I went with the stock size large BTR Ranger 26" wheeled bike, but lowered the top tube and reduced the seat tube to 400mm. Should I ever want to have the saddle up to XC height, I could raise a 400mm seatpost to max height (300mm extension, 100mm in the seattube). But pretty much always I have it slammed. It required a stronger seattube (Reynolds 851 instead of 631) but it could be done and I'm super happy with how it worked out. But once you have such a starting point, it may help to get ideas how another bike could be made good. For instance I'm happy with my front-rear balance. If I'd get a full suspension bike, it could be longer but I might still want a similar (sagged) front center rear center ratio. And you're not just going to throw your design over the fence and have it built. At least not with an European builder. You're going to discuss it to check whether it is actually going to work out as you hoped it would. And you're going to work with a builder that may share your vision. I have my midfoot over the pedal axle so I feel this works well with a short rear center and longer front center. BTR bikes are like that (my bike has a 415mm rear center). For instance Nicolai may not like to go there.

So yeah, start with a design you already like and work from there. And with some brands like Starling and Curtis, it is almost standard to have some geometry numbers custom.
  • 5 0
 I agree, I'm sure I couldn't bang out a better bike than what I'm on currently, but I'd love an adjustable chain stay to tweak for preferences.
  • 1 0
 @vinay: yep my Curtis am7 was custom all over. Head tube size and angle. Seat tube height and angle as well as reach and fork travel which changes headtube location. Beautiful frame.
  • 2 0
 I,'d be pretty damn happy just being able to specify a 485-490 reach and 650ish stack. Maybe the hta and sta a degee. Maybe add 5mm to the stays. I don't want to design a bike, just tweak.
  • 2 0
 All that but Curtis doesn't offer a provision for 29x3.0 tire clearance@mikelee:
  • 3 0
 @Tigergoosebumps: the am7 is a 27.5 frame. You’d want the am9 for 29er. Max tire is 2.6 I think. For the type of bikes they are I only use 2.4 anyway. It’s a fast,very light,aggressive hardtail.
  • 4 0
 Same. In an ideal world I'd like to uncouple the choice of geo from the choice of bike. I'd like to pick the manufacturer based on warranty and support, bike model based on travel/weight/components and then have the geo tweaked for my particular body dimensions, the steepness of the terrain I usually ride and my preference for a poppy or plough bike.

In other words, more made-to-measure than bespoke.
  • 3 0
 Remember that "what innovations would you like" article from a week or 2 ago. This is the innovation we need. With 3d printing, digital inventory and CAM, the buyer could select from a limited number of +- 20mm TT, +- 2deg HTA etc for an upcharge. Easier for a welded (or Atherton style) bike, but I bet you could cost effectively machine 1-off moulds from a softer material that could only stand a couple of bikes
  • 1 0
 Completely agree! I wouldn’t want to start from scratch but I’d like to at least customize for my body dimensions. Maybe it would simply be a bike fit tool like on BikeCAD rather than me choosing the geometry numbers
  • 2 0
 THIS. Working out everything on my own would be a hassle, but I could definitely do a few tweaks.
Trail/enduro bike i just want a mullet bike with the shortest possible chainstays and a BB that is a bit lower (use shorter cranks)
For a slope/DJ bike i want a 71 degree HTA (yes a degree or 2 steeper than most) but I also want a 30-40mm longer top tube so the 26" tires don't catch my toes on Barspins or X-ups.

I would probably have royaly screwed up bikes, but at least it would be mine.
  • 4 0
 @mountainsofsussex: pretty sure that what kavenz bikes does you can custom spec reach and a few other measurements but not the whole bike. For me that that sounds like the perfect middle ground
  • 1 1
 Most brands don't allow you to play with the dimensions of the rear triangle, but there is a lot you can do with the front. Just look at the respective pages of Nicolai, Curtis, Starling, Project XII etc. Probably goes for Kavenz too. It is impossible for them to set exact limits as so much is related that it is better to just start the conversation and discuss your ideas. They want to be sure about the chain line, tire clearance etc. And they also recalculate for strength. As mentioned, I went with a shorter seattube, they did the computer simulations and decided it could be done but required a stronger tube. You're going to want their input so you'll start with a brand that has bikes that are already close to what you're looking for. So if you're looking for a no-frills jump bike you may like to work with Curtis. Whereas if you really do appreciate the frills, Project XII or Portus Cycles may be a better fit. Either way, I think there is a bike builder for everyone. Do people need a custom bike? Likely not (though no one was mass producing exactly what I was looking for). Then again, I read somewhere that people buy a new mountainbike every three years or so. I'd say that once you've decided what you're really looking for and are having it built (in the color you like), you're going to hold on to it for much longer.
  • 2 0
 @vinay: absolutely and do agree the most people don't understand the affect of moving pivots and change it would cause in leverage rates ( I bearly understand it). But tweeking frame geometry a little reach, STA, HA and seat tube length. It would really dial in a bike for most people. But the problem with choice is you can make the wrong ones
  • 1 1
 @briain: With things like suspension, I think it is hard to get it right. The big brands think it out, then build the prototype to test and tweak it for the final design. They may even work with a mule in the mean time to try different settings. If you jump that, you basically just get to ride the first prototype. It may work out as of course, part of the tweaking is because they have to make a production model that works for more than a few people whereas you just get a bike that works for you. But yeah, I wouldn't dare to mess with that. But also because I have little (good) experience with rear suspension. With geometry, it is different. You kind of do know what amount of room you want over the bike, how you want to move around etc. If you aim for a certain front-rear weight balance, that may be doable too. But the actual dynamics, working with head tube angle and trail and all that, I think it can be tricky. But if you already have a lot of experience on a certain bike that's close, you may have an idea of which direction you want to tweak it into. But yeah, it is a commitment. I was pretty safe just lowering the top tube. I trusted the builder on the rest of the geometry.
  • 1 0
 @briain: I love what Kavenz have done. But they're such low volume that custom is less of a disruption. I was thinking of the big boys - like Trek Project One or Orbea MyO, but with geometry rather than just paint and some components
  • 1 0
 cannot say better
  • 1 0
 @mountainsofsussex: granted they are low volume and everyone who offers any form of customisation are using metal as a frame material. But if you look at how forbidden bikes change the chain-stay length on their bikes for different sizes its genius so there are ways of doing it. Also I have heard of racers mixing and matching different parts from different frame sizes to get what they want out of their bikes. If brands shorten their supply chains and move closer to in house production these things become possible but extended supply chains across the world just doesn't make it feasible
  • 1 0
 @mikealive: so an s3 enduro?
  • 1 0
 @briain: I looked at their numbers and the range of reach and 440 to 540 is pretty good but they don't have a 470 which in my mind is would be the ideal reach. It goes from 460-480, put in a 470 and boom
  • 108 7
 Love the overconfidence of pink bike readers Smile
  • 16 12
 So many deluded people.
  • 15 1
 Talk is cheap and bikes are expensive.
  • 3 3
 Lol, had the exact thought when I saw the poll results
  • 4 3
 Does it really matter, everyone is going to do whatever Pinkbike tells us we need and want in the end anyway.
  • 13 0
 I know myself all too well- I’d get all psyched about doing “my own custom geo”…


And then just end up surfing bike sites to copy what ever looks good or has gotten a raving review about how well it rides.
  • 6 1
 Right?

I’ve built about 10 frames, and the first one was me choosing what I thought would be best, based upon “current trends”. It was not a good mix. I then just started copying Specialized geo and doing minor tweaks. Individuals must have large time resources to prototype and test geometries. So I will rely on someone else to do the field testing. Thanks!
  • 2 0
 To be fair, it's likely that many Pinkbikers buy/change bike frames much more often than the general public, and that this gives the ability to directly compare different geometry across frames. I know that I have found myself thinking, "if I could just have the reach/stack of my previous frame, married with the chainstay length, seat angle and suspension kinematics of this frame...."

I think it would be tricky to reinvent from scratch, especially when accounting for the entire bike as a system. But I am confident that I could tweak things on my current rig to make it fit my exact proportions and riding style.
  • 3 0
 Geo is quite easy to figure out what you like. But try to match good kinematic is a way more complex thing!
  • 36 1
 Yes definitely. With my engineering degree earned from cruising PinkBike forums, I absolutely can make better decisions on geometry than a bunch of dorks that wasted all those years in college. I bet they don't even ride bikes. Excuse my while I go and whip up some homemade ivermectin to ease my sore throat and hacking fits.
  • 2 0
 I'm there with you. Once you make a given number of Pinkbike comments on bike reviews, I think you should receive a framed certification that ordains you an official bike engineer. Smile
  • 3 2
 I think you overestimate what you can learn in college about bike geometry. It seems so simple at first glance, but the numbers affect eachother in so many ways, that finding a good geometry is more of a trial and error process. That's why i'd trust the average reader of pinkbike to come up with a better geometry than the smartest engineer who never rode a bike.
  • 2 0
 Do you guys really believe that the recent improvements in geometry, were the result of some break throughs in engineering?
  • 25 1
 "I don't think it's that hard" is relative I guess. There's some numbers I know very specifically from bikes I've ridden and I know what I prefer for a certain style of bike. All the usuals like STA, HTA, Reach, ETT, BB height, chainstay. I'm all good with those. So basically if I was doing my own thing I'd steal an existing bike's numbers that I'm familiar with and then tweak 4-5 things. So is that really my own geometry?
  • 22 1
 I think most people overestimate their engineering abilities. Especially if you want a water bottle in the triangle.
  • 4 1
 @gnarlysipes: No doubt. We’re not engineers, but we play one on TV. Also, we stayed at a Holiday Inn Express.
  • 1 3
 Not really relative, unless you're so narcissistic that you overestimate your own ability. The majority of people here (including you) would struggle to make a decent single pivot suspension bike, let alone actually know what they're doing when all of those values are blanks.
  • 5 0
 If we're saying custom is grabbing an existing frame that we like and making a couple adjustments I think that's within the ability of many keyboard engineers here. Starting from scratch... probably not so much. Some of us could probably do better and design something that "works," but would it be worth pursuing when it probably still wouldn't be as good as the a fs design from an established company?
  • 22 2
 My custom geo Marino hardtail is complete and should be shipped in a few days for only $430 including shipping.

160mm fork
29x2.8 clearance
460mm reach
425-435mm chain stay (sliding dropouts)
77° seat angle
65° head angle
Two bottle mounts inside frame plus 2 more tool mounts

Not the most extreme geo, but I'm excited to ride it!
  • 2 0
 Nice dude!
  • 4 1
 Sounds nice. I've got a marino made for my friend with conservative geo,for bikepacking and easy trails. It rides very nice,but feels very stiff/less compliant than my Stanton,but cant beat the price! Lots of people go full retard on wild geo, guess some will regret it..
  • 4 0
 Curious how that seat angle will feel pedaling on flat/rolling terrain, especially with that big fork sagged
  • 4 0
 @VtVolk: and in Minnesota, no less... So it is a lot of flat and rolling terrain.

I also double checked my geo and I have a 64° head angle.

And, my fork is currently at 180mm and I may try it that way first. Seat angle will be a bit more slack then.

So, yeah, I am anxious to see how it goes. May feel awful for all I know, but it's within the extremes of several other frames that had glowing reviews the past few years.
  • 2 0
 I built one up last year and I'm really liking it! I combined the back of my dirt jumper and the front of my enduro bike into one everything bike 160mm fork 26x3.0 420 reach 390mm chain stays 65 degree headangle
  • 1 0
 Gonna feel heavy on the arms with 77deg seat tube.
  • 1 0
 @littleskull99: I suppose I'll find out once I get it on the trail! I have a 2020 Stumpjumper as well and this is my first attempt at custom geo, so if it doesn't work out for me, I can move on.

And like I said above, I'll actually have a bigger fork initially, so it will probably be more like 76 and I'm going to run a short stem and a decent rise on the bars, and probably a few spacers under the stem just to keep the steerer long. At least to start so that I can make adjustments.
  • 1 0
 That's a serious STA with a hardtail.
  • 3 0
 @yupstate: But not unheard of either. Chromag Doctahawk is 76.5, Canfield Yelli Screamy is 77, On-One Hello Dave is 77, Marin El-Roy is 78, etc. Those bikes all seem to have cult followings, too, so maybe they are on to something.

Figured I'd give it a try. If needed, I can slam the seat as far back as possible. If I still don't like it, I can sell it and move on to my next project. Really not a big deal.

The truth is, neither of us have ridden my frame yet! Hopefully it works out for me, but I'm smart enough to know that it is possible that I missed the mark, too. I'll find out in about a month Smile
  • 1 0
 @tpfenning: Well I hope you like it, if not please come back and post here for those of us that thought possibly it was too steep. That would add value to my day for the money you spent. It's very important to me for me to be correct! Smile

Seriously though it depends on the terrain and your height along with the actual STA. It's going to be steep, there's no denying that. But if the terrain is straight up and straight down then it should be ok. Also if you're tall that helps.
  • 2 0
 @yupstate: I'm 6'1" (185cm) so not super tall, and my terrain in Minnesota is definitely not mountainous. A 64⁰ head angle (double checked my geo) and 160mm forked hardtail is definitely overkill from the get go.

And I'm going to run it at 180mm to start which will push the HTA closer to 63⁰, so I'll have other things besides the STA to worry about as well.

I already had a 27.5 180mm fork, which is what the geo was designed around, but I wanted room to swap 29er wheels in at a later date and a 160mm 29er fork is the same axle to crown as the 180mm 27.5 and that's the reason for the sliding dropouts as well.

But then I found new 29er lowers for my Yari for cheap and decided to go straight to 29er, but didn't buy a 160mm air spring yet.

So there's a bit of the journey I went on. I'll report back how it feels, but like you said, it's going to be a handful of factors in the end.
  • 1 0
 @tpfenning: Wow, quite the story there. Go mullet and you're STA will level out a bit. Sounds like it may be a stale grim donut........stale = hard...tail? Anyone? Nope nobody's laughing.
  • 1 0
 @yupstate: Frame came last week! You can see pics on my profile. STA with the 180mm fork without sag is sitting at 74 and HA is way back at 61.5, both by my phone app, so teaspoon of salt. I had read somewhere that Marino geo is at sag which might explain why it's slacker than I expected at static. I figured it would be 1-2 degrees slacker with the extra 20mm in the fork, but it's double that. BB drop is at about 20-25mm, compared to the 35mmin the geo chart, so it all makes some sense.

I've never ridden a bike like this at all, so I have nothing to compare it to besides my old Capra and my current Stumpjumper. I haven't had it on the trails yet, but scooting around the neighborhood and running the front end pretty soft (~25-30% sag), it feels really good!
  • 17 0
 Years of development with engineers and some of the world best riders... I ride two weeks and watch a lot of Youtube... Of course I know better... We are entering an age of the over confident and under qualified and every opinion is as good as an education. Most people can't even set up their suspension, but let's give them the keys to the castle!
  • 4 0
 Amen, man. I know a lot of people here are just full of poop, but I had no idea they were this deluded.
  • 4 2
 Exactly. Years of development with engineers and professional riders, and then some knucklehead slaps on angle set in it because "he knows better."
  • 14 0
 Steve from Hardtail Party recently got the opportunity to design his perfect bike from scratch. He rode a prototype with his planned dream geometry and even then did minor revisions to some of the measurements. Getting it right is obviously an iterative process.
  • 2 0
 I've built a bunch of frames for mostly myself. I definitely prefer designing/building hardtails (and it's been an iterative process!), but full suspension bikes... nah. Give me 4 models that will hold up and are good-ish and i'd rather pick between them. There isn't a raft of institutional knowledge for a designer to use, the interaction with evolving shock tech makes it hard, and i don't wanna have a compromised FS bike even if it's great at 1 thing.

Modern suspension bikes are amazing.
  • 13 0
 Could I lay out a geometry that'd fit my body and my preferences really nicely? Absolutely.

Could I lay out that geometry and have it work with pivot placements and a suspension design that I actually like? ehhhhh... maybe.
  • 1 0
 So just take an existing suspension design that you like and change only the measurements that matter to you.

I did that with my current bike, adjusted that head angle slightly and asked for a little more reach (I felt I was between two standard sizes). It cost Euro 150.- extra at the time, and Federico at MDE bikes did a marvelous job - it’s simply the best bike I’ve ever ridden.
  • 9 0
 My custom geometry would really just tweak certain dimensions so it would be an ideal fit and would base my ride on something along the lines of a Stanton Sherpa, Kona Unit X or perhaps a Cotic Solaris. I'm one of those riders whose height, inseam and arm length places me between a small and medium in many brands. I have a slightly shorter inseam but longer arms which can complicate things. For the riding I do the most - multi-hour rides on doubletrack, green or 'light' blue singletrack along with 'gravel' sections - means I don't really need the slackest geometry and longest reach. All day comfort and practicality (yes to water bottle bosses) is most important to me.
  • 10 1
 And again: it would be nice if the selection of answers would not make you sound like an absolute knob!

I understand that the majority of commenters behave like a 14 year old, but do the editors also have to?
  • 6 0
 Where is the option for "I DO know about numbers, but I think the bike brands do a great job."?
  • 4 0
 And the typos of a teenager, too ("brandss" and "a your")
  • 11 0
 I’ll stick to carpentry
  • 2 0
 @FatSanch: funny looking bike! I’ll stick to my Yeti :-)
  • 7 0
 Anyone who thinks designing and building a frame is easy should try it some time. It's a lot more complicated than it looks and it's easy to sit back and trash talk someone else's work when you haven't produced anything yourself.
  • 5 0
 I think the geo has been pretty well discussed and most here know what they like. The harder part in designing a bike is tube profiles or carbon layup. How stiff is too stiff etc. I was lucky enough to work for a framebuilder and got to make my own steel hardtail. I knew what geo but had to discuss at length, what tubes and what butting I wanted because I had no idea. Could have ended up being 3kg and stiff as or under 2kg and noodley. Ended up right in the middle and my ankles are all the better for it.
  • 6 1
 There needs to be a stronger response than "Yes absolutely". Manufacturers in general seem to care less about any product the further away from medium you get. Bigger (and smaller) than average riders need good gear as much as the averages, and this would be a good way to get it!
  • 5 0
 Calculating the optimal geometry for a bike means 1 Choosing the compromises you want for this bike's intentions. For downhill or triathlon bikes, there are very few compromises to consider. But for mountain bikes that are to be pedaled up and ridden down in a variety of terrain, there are many. 2 Matching those compromises to the your own body dimensions by picking the correct lengths and angles. This isn't very hard for yourself if you have experience on a few different bikes that you rode extensively in the variety of terrain that you like. It helps of course if there was at least one bike you liked, and you know what lengths and angles they have. I don't buy new bikes very often so I actually am not sure whether I would still like a longer, slacker bike than I have now or it would be too much on steep techy climbs. It may take some adjustment in riding style, which takes time. Same for the amount of travel. Sure, there are times when I will love that. But my close to home trails may be better on the XC-ish120mm bike I have now. This is why I would answer 'no' to this poll. I do not yet know what I want. Still, I am pretty certain that if I would take my current bike and steepen the actual seat angle by 3 degrees I would like it better.
  • 4 0
 Understanding the geometry and their relations to one another is exceptionally complex. You change one thing and affects the others. It takes designers and engineers a lot of time to come up with figures that work with suspension kinematics, pedalling efficiency, different sizes, etc. A lot of people could probably come up with some basic numbers if they were keen and looked at a bunch of geometry charts, but it would likely be a best guess.

I think it would be cool if a manufacturer had a configurator of sorts. You enter in your weight, height, riding ability, and answer some questions about how and what you ride and it spits out a set of geometry figures to match. The geometry could be within a pre-defined, engineered range to ensure that all the kinematics and critical performance aspects of the bike are maintained. This probably already exists, but I haven’t used one.
  • 5 0
 Robot Bikes… I mean Atherton Bikes does that. A few years ago it was essentially a play on the 2015 Giant Reign.
  • 3 0
 Definitely. But maybe not fully bespoke- given too much leeway and choice, I could make a real mess.

Getting to take a production bike and tweak it to my liking would be killer. On my Ripmo, for example, I would slacken the head angle a bit, slacken the seat angle (I have stubby legs, and often feel too far forward pedaling) and adding a little to the chainstays would suit me perfectly. It's not that the bike is wrong for me, but it could be even better with some small tweaks to suit my stubby legs and long arms.
  • 5 0
 honestly i'd be super stoked if more companies had the M/L size, like chromag does. i'm exactly 5'10" and that puts me right in the middle of too small or too large.
  • 1 0
 Yeah, my custom geo would pretty much just be between a modern L and Xl frame with most companies.
  • 1 0
 Exactly! Trek’s M/L is perfect (I’m 5’10 too) could go for a large, but then the whole bike feels really tall. The in between size is great for having a more maneuverable bike
  • 5 0
 I feel like really short chainstays have fallen out of fashion but my old canfield balance with 420mm stays was just so fun and I never felt it to be a detriment.
  • 3 0
 I wouldn't trust myself to start from scratch. But if there was a company that could take my measurements and understand my riding style and design custom geo around that, there could be a marginal benefit to buying a standard size from the same company.

That being said, humans are adaptable. A good rider on "bad" geometry will outride an average rider on optimized custom geometry. I think my money would be better spent trying to become a better rider.
  • 2 0
 Probably not. I mean I roughly know what I need and there's usually a size to cater. But sometimes you can fall between sizes... Luckily the extremes of geometry have been done now, been reeled back in, and decent geometry is available! And most frames have some sort of geo adjustment. So no, no need really these days. Couldn't find this option in the poll.
  • 3 0
 Anytime you are buying new bike, u sorta choosing "geometry for you", it is not tailor-made for you, however it is the most closest geo that will suit u, besides brand loyalty;
  • 4 0
 5 years ago it would of been important to customize your geo. In this era there are enough production options that it's not necessary.
  • 2 0
 I think for the most part "geometry" is pretty bang on these days - the problem is the sizing. For me as far as reach is concerned I'm definitely a XL ~500mm, but if we're talking eff. Top Tube usually prefer a large ~425-430mm. While seated and climbing I want to be over the pedals and upright as possible, not lunged forward in all out XC mode, but descending definitely want to be more stretched out and "in" the bike.
  • 2 0
 I DID-and saved $$$$. 64.5 hta 75 sta 435 chainstays, 485 reach 631 stack 55mm bb drop, 1248mm wheelbase. I didn't want to compromise on something with dated geometry or overpriced components, then play the upgrade game where I'm constantly trading for last year's model because after eons selling everything from Kias to Porsches to houses, I've come to the conclusion modern bike values are a f*cking joke.
  • 2 0
 Custom geometry doesn't need to be crazy weird out there. I know what I want in my next small travel dualie frame my only problem is I want it 27.5 which sucks because it pretty much exists in a 29er. But I already have a bigger travel 29er I like, and I ride my 26" dirtjumper 4 nights a week. I want a crossover poppy slappy jib bike.
  • 2 0
 The re is a limit to where bikes fit and handle well given each rider and the terrain they ride in. Understanding your own 'rider profile' is key to being able to choose what is going to work best. Go to an area that is completely different terrain and your sweet spot drifts away a little. Where I live the uplift options are limited, which doesn't bother me tbh, and the terrain is rolling. So a bike that climbs well is a must really and then fit comes into play as a priority and seated climbing on a bad fitting bike is just making your riding harder. Starting with a bikes set of numbers or starting from scratch doesn't really matter. There are soft limits anyway so it's not like you'll and up with a bastard child of a bike. What ever number you tweak still means a custom frame to be made. Some of the brands have had bikes with some adjustmenst and they kind of have to do that to try and appeal to as many people as possible. Smaller bespoke brands can pretty much cater to any request as part of the normal part of ordering a frame. Though any builder who has got their bikes dialled will have a starting template to work from and tweak to suit, but still keep the character of their bike intact.
  • 4 1
 As an engineer, BMXer, I would make a great custom bike!! Seriously though, it would be nice to be able to make some very slight changes on a bike.
  • 3 0
 "Engineer" is great and all, but that you have a BMX background is the key.
  • 2 0
 Being short with short arms and legs, I'd like a small thats actually small something about 400-410mm reach would be nice. Some nice new bikes out there but far too long for me even with a 10mm direct bolt on stem.
  • 1 0
 Some brands offer "junior bikes". Check out Commençal and YT.
  • 2 0
 Building in a custom stack to an existing bike could clean up the front end and add a bit of rigidity. Adjusting the seat tube angle together with reach would help tall riders and in between sizers.
  • 6 1
 63 hta 78 sta 480 reach 650 stack 430 chainstay
  • 3 0
 question two is excellent. Would your custome geometry be any good. No, id spend time effort and money designing my own custom geo specifically to ensure it's utter crap.
  • 1 0
 I think a lot of people would like to be able to make a couple of small changes to the manufacturers dimensions. For example, being old, riding steep trails, I’d usually like a slightly taller front end relative to the seat in the down position, without the shortening effect of spacers and high rise bars. Actually thinking about it dropper posts getting longer has reduced that issue somewhat.
  • 1 0
 Τhe custom geo bike I'd design a few years ago is currently offered by quite a few brands in one form or another. Apart from the ridiculous price increases and availability issues it's a great time to pick a new bike - chances are it will be great. Even XC bikes are getting slacker, which is a big step in the right direction.
  • 1 0
 I ride a custom bike - a Dead Rabbit Geo29 handmade in Switzerland by @Swissracetech ! Awesome bike, and perfect for me and for how I ride!!!
I'd be riding just fine with a Stumpy Evo and standard geometry, or with something similar, but the relationship with my Dead Rabbit is completely different. It's personal, it was made for me, according to my preferences, and it was made by a good friend. This bike will stay with me, even when I get a new bike or two sometime in the future.
  • 1 0
 what would be best is a bike with highly adjustable geometry. I would like to be able to experiment on the fly with your head angle from 73 to 55 (not a bs 63.7-64.2) and lower your BB really low. I reckon you could get a bike that is a blast to ride in SOME conditions. Geometry is a compromise and it would be nice not to have to compromise.
It would also help to fie tune by being able to experience some extremes.
  • 2 1
 Wow, lot of self-confidence being displayed in those poll results. Never realized Pinkbike had such a large following among engineers.

There are sometimes things that feel "wrong" on certain bikes, but I know enough to have an idea what I *don't* know, and most likely any changes I tried to introduce would have knock-on effects that would be horrible.

I also know I'd buy that $250 seat-angle adjuster, that everybody in the comments panned, in a hot second if it were more affordable. I suspect that would fix a number of issues I have that result from the balancing act of a good descending geometry vs good climbing geometry.
  • 3 0
 Have my custom geo Marino hardtail on its way. It’s a big of an experiment but can’t wait to see how it builds up and rides
  • 1 0
 Mine is finished, just waiting on delivery sometime in the next few weeks!
  • 1 0
 I built one up last year, It rides pretty nice, I essentially combined my dirt jumper and my enduro bike to make an everything bike, it has 160mm of travel, a lot of reach, very short chain-stays and 26" wheels!
  • 1 0
 Anybody who has been riding bikes for a long time and spent a ton of time and money on bikes, likely knows what geometry metrics fit their body and riding style. This is why Atherton bikes is a great idea, but the pricing of those bikes are expensive. Therein lies the conflict. Wink
  • 1 0
 Custom geo. on a bike is great as long as I can use my bmx parts, carry more than one water bottle, and have to buy a new set of wheels for a different dropout standard so I can still complain about something. Oh yeah, and there should be room for a battery and a motor. A custom bike should make biking more accessible to under represented user groups!
  • 1 0
 Geometry will settle down just like it did for motorcycles. There is a performance sweet spot for each discipline. Everybody will get there. Pushing the boundaries today will help zero in on that sweet spot. I wish Santa Cruz would have kept a couple top driven shock models in their lineup. It was lighter and poppier.
  • 1 0
 64.5 HTA, 475mm reach, 76.5-77 STA, 440mm chain stays. 155/165 adjustable travel like GG had with the crush/plush modes. 170mm fork with short offset. 100mm head tube, any longer (at least on my current bike) feels like the bars are too high. Ideally the shock would be mounted low (like any one of a number of bikes that “look like a…”) On bike storage is a must, either with a strap or I’m frame box. I like the OG Swat bolt on box the best. I ride in WNC all year long, so mud protection has to be thought of. Seen too many Smoother-outler’s get the linkage all messed up from debris. Plus room for a medium bottle in the front triangle. Throw in the usual boost spacing, threaded BB, 34.9 seat tube and it’s good to roll.
  • 1 0
 Adjustable HTA /reach, I'd take 1.5 degrees /1.5cm, the rest you can do with modified fork travel/sag/front wheel size, handelbar stack/rise.
Adjustable shock mounts, Rocky Mountain type both ends of shock (trunnion mount go to Hell).
Adjustabla CS, >1.5cm.
And you can experiment as you like and adapt to terrain and changing riding style.
I don't trust bike manufacturers will or can guess what is best for me.
To those who think I am overconfident: if you're passionate enough you can get some great results, todays designers had to learn too to get where they are.
You'll make some mistakes along the way but so did they and it is part of learning process.
  • 1 0
 Only thing I have ever wanted to alter is seat tube length; to accommodate a decent travel dropper post (stumpy legs), but component manufacturers have sorted my problem with short stack, adjustable travel droppers. Now I'd just leave it stock and benefit from the companies' development budgets.
  • 1 0
 When a football player (soccer for some) misses a goal, the old saying goes: I could have scored that. If the pro engineers and designers who work at the bike industry are still fiddling with micro adjusts (bikes are around for a long time now), it probably isn't that easy. But take notice that, in some areas, custom geometry, supported by the brands costumer service and available for certain areas of the frameset, already exist (check some premium bike brands or independent builders, for instance, and hence the word Premium). For the sake of the argument, I think there should be some costumer programs that could allow you to choose some geo tweaks from a given base. The bikes are so expensive now, I believe some could have some form of custom geo option.

Food for thought, if bike brands start allowing for a full custom geo, wouldn't they loose all their identity? Basically, you just had to come with a technical drawing and present it to any brand... Who cares if it Specialized, Yeti or Norco.
  • 1 0
 I think I could sketch out a hardtail geometry from the top of my head. Of course it would be roughly based on the bikes I know and currently ride, with a few tweaks (think bb height, seat angle, stack etc.). Suspension layout? Nah, I'll leave that for the engineers.
  • 1 0
 I wish I could modify one or two things and have the other measurements automatically adjust in a way that would mostly maintain the intended handling. As a short guy, some bikes (mainly older CX geo) have standovers that are too high for my inseam, there may be a size or two that does have a standover that fits me but they are like a size 47cm and made for someone that is like 5 inches shorter than me in terms of the stack and reach just because I need like 2-3 cm less in standover... The first bikes that come to mind for this are the previous gen Specialized Crux (current one is fine) and the current Specialized Epic Evo. 780mm standover heights make me cry.
  • 1 0
 64.5 HTA, 475mm reach, 76.5-77 STA, 440mm chain stays. 155/165 adjustable travel like GG had with the crush/plush modes. 170mm fork with short offset. 100mm head tube, any longer (at least on my current bike) feels like the bars are too high. Ideally the shock would be mounted low (like any one of a number of bikes that “look like a…”) On bike storage is a must, either with a strap or swat box. I like the OG Swat bolt on box the best. Plus room for a medium bottle in the front triangle.
  • 1 0
 My first experience with custom geometry was when I was racing BMX all over the country. Fit like a tailor made suit. Amazing. I did it again when I had a Ti fat bike made. And then again with Marino for a custom flat bar road bike for a commuter. If I had the money, I'd definitely do a full-squish custom geometry frame as well. A lot of frames max out at 2.6 tires in the frame. I love to run 2.8 on 40mm rims. II can do that on my Patrol (201Cool , so if something happened to that bike, I'd struggle to find a new frame that could fit my wheels. Also love a shorter chainstay than most people. shorter than my Patrol I've tried enough different frames to know what angles feel best to me too.
  • 1 0
 I'd be interesting in trying 10 different geometries to see what feels best, and that's the only way to truly get a good fit.

I don't mind a 510mm reach, but it's on the stretchy end–but haven't tried anything close for reference. There's not much else I would change ... I think 65 HTA and 76-78 STA is a good starting point for my riding style.
  • 1 0
 I think the wheel size, wheelbase, fc/rc ratio, st height, reach and stack height are dependent on rider size.

Geometry angles should be based on terrain.

And finally tube profiles, butting and thickness is all about the strength to comfort ratio.

Just my opinions, 30 psi in my minions.
  • 1 0
 I trust the geometries of the designers, the only measure on which I would like to customize is the seat tube length. I would like it as short as possible combined with longer dropper posts. It is not nice to evaluate the shorter size than yours because the seat tube is too high.
  • 1 0
 Could I? Sure. Worth it? Not at all.

Some folks really do benefit from true custom geometry, just like some folks really benefit from custom skis or footwear.

Most of us fall within the bell curve of “average” proportions and do just fine on stock frames, with maybe some suspension tweaks to get things juuuust right.
  • 1 0
 All I require is an XL frame w/ a 460mm seat tube w/ a nice steep angle, giving me a short top tube w/ a decent reach! Unfortunately, a lot of brands are still making XL frame w/ 490mm seat tubes which is too long for anything but a 150mm dropper Frown
  • 2 0
 Of course I would, that's why I did exactly that. And to no surprise, it fits me perfectly and works extremely well for it's intended use. The only reason I haven't done it again, is cost.
  • 12 12
 Arm chair engineering at it's finest. Thinking you could pick your own geometry and make a bike that's better or even close to one from an existing brand is like saying you could cook a 5 course meal like in the next michelin star restaurant.
  • 3 0
 In this case we don't have to guess what the chef is doing. Everything's already written down.
  • 3 1
 New, small brands constatly releasing competetive products should tell you, that the "industry leaders" dont have to put in a lot of effort.
Choosing frame dimensions isnt even engineering, its design and anatomy.
  • 1 3
 @endoplasmicreticulum: Those guys are also engineers, have most of the time worked with or at another brand like forbidden being started by former norco employees. This wasn't a compliment to big industry brands but a statement about the people of pinkbike who think they know what goes into the process of make a bike work. Even if "it's just geometry" I think most are underestimating how much goes into such a process. Not to be insulting but I wouldn't trust the same smothbrained motherf*ckers who post "looks like a session" under every four bar design bike with designing a bike themselves ...
  • 3 0
 100%
The exact geo I want for a bike to be for my next bike doesn’t exist, and only 1-2 bikes come close.
  • 2 0
 I wonder how many people would spend the extra dollars on custom geometry that's basically identical to off the shelf modern geometry out there today.
  • 1 0
 I have no doubt I could pick geometry numbers to make me happy. Getting my desired geo numbers with good suspension, water bottle bosses and reasonable frame weight? I’ll leave that to the real engineers.
  • 2 0
 I have designed several of my own bikes, and I'm trying to bootstrap a bike company precisely because I wanted my own geometry!
  • 4 1
 Modern bikes have geo nailed. There is no longer a need to change it unless your 7ft tall.
  • 2 0
 Based on no experience at all, I get the impression we've settled (or are very close to settling) on ideal angles for each different category of bike. Some of the lengths probably still need work though.
  • 1 0
 Basically all I could do is set up the rider triangle and get the head angle somewhere about 64 degrees for enduro and maybe get the BB height, but don't ask me reach numbers or chainstay length.
  • 3 0
 Get a MDE, done. Best bikes for the money, custom geo high quality made in europe for 20 years,easy.
  • 1 0
 I've done custom geometry on two different bikes and both turned out great, and there is soon to be a third. (albeit the first one was great 5 years ago when it was built, less great by modern standards)
  • 1 0
 The key - to me - is more oil volume than less in the rear shock. Too often I find shocks over-leveraged and underdamped. I think Foes and Curnutt understood this, but most other suspension manufacturers do not.
  • 1 0
 Yes - being in between a medium and large can make it tricky finding a bike that fits right. But... you also need to think of resale, it might be difficult to sell something that's specifically customized for you.
  • 2 0
 I just want more manufacturers to make to chain stays longer on size XL frames for better balance especially during seated technical climbing.
  • 1 1
 What about seated or standing smooth climbing, or standing technical climbing?
  • 3 0
 Modern bikes have stellar geo in general,. This poll is about 5 yrs too late pb.
  • 1 0
 64* HA, 78* effective STA, 425mm CS, 500mm reach, lowest seat tube and standover in unison with the longest dropper possible for the most leg clearance/bike maneuvering. Around 160mm fork, 140mm shock. 29 or mullet.
  • 1 0
 I don’t have issues with geometry. What I would change is where the water bottles go. A cm here or there would make it so much nicer, but it like they just stick to the same place for all sizes.
  • 1 1
 The irony of it all is that after countless hours of studying and brainstorming, that geometry that they just had to have is completely gone to pot. Simply because they can't get even their spring rates right and are running 20% front and 45% rear dynamic sag...
  • 2 0
 I’ve worked in shops for years. Every damn bike nerd thinks they know more about bike design than the highly paid engineers that design bikes.
  • 1 0
 the question Would a your custom geometry bike be any good? is a difficult one,

for me yes, as I know what I would like and how i would like my bike to feel, would it be any good for anyone else, no no it would not
  • 2 0
 You follow the the pros when it comes to design. Cheat off everything you like and change what you don’t. Easy!
  • 2 0
 I am genuinely happy with my current bike, so don’t feel the need to mess about with geometry.
  • 2 0
 “Yes absolutely I know best!” Should be “ I know what fits me and what I like”.
  • 3 1
 Real question should: Does Levy still work for Pinkbike? Haven’t seen his graceful touch on anything in a while.
  • 3 0
 With a G1 lots of geo options are possible and changeable.
  • 1 0
 How about we just get bikes that allow angles to be adjusted by the user? Ie: chain stay flip chips, ZS56 headtube, linkage flip chips…
  • 1 0
 I adjustable geometry. I don't know that I would want to make a fully custom geo bike. I would be into it if it were also adjustable geo
  • 1 0
 There are so many bikes out there. If you dont have an fetish for getting money pulled out of your wallet by a specific brand its hard to not find something suitable.
  • 1 0
 Did it, copied the numbers I liked and tweaked them and still wasn’t right. Off the peg is generally better, tried and tested
  • 1 0
 Copy the geometry of a modern long and low bike, except steepen the seat tube enough that we can reach the handlebars. Perfect bike.
  • 1 0
 It's definitely doable if you take the time to learn all the details and have access to the materials and toolls.

ep1.pinkbike.org/p5pb22214363/p5pb22214363.jpg
  • 1 0
 Most bikes have a flip chip nowadays... should have asked in the poll how often we change it.
  • 2 0
 MDE bikes offer custom geometry for 150 euro extra
  • 2 0
 EZPZ Reach, stack, CS length HTA and BB drop. Thats it!
  • 2 0
 Speaking of geo, what's up with the grim donut 2??
  • 2 0
 Yes but it would basically just be a geometron g1 in between 2 sizes.
  • 1 0
 Sure I could but why bother when most brands are pretty much on the money these days?
  • 1 0
 you can already do this??? boot up solid works and call your local machine shop ladies
  • 2 0
 THX FOR THE TYPO @OUTSIDE
  • 1 0
 Hah! Geometry is the easy part. Suspension kinematics is where MTB designers make their money.
  • 2 0
 Damn beta articles clogging the lineup
  • 2 0
 64 HTA, 78 STA, 485 Reach... mhmhmhmhm
  • 2 0
 Pretty easy, right?
  • 3 0
 So a Large Sight? Well 77.7STA but yeah. Have one is great.
  • 1 0
 I think I could do a pretty good job on the general geo, but I would definitely need help on the linkage/suspension design
  • 2 0
 Would a your....
Say what now?
poof weed much..drug testing?
  • 1 0
 Did somebody say poll, Pole? My Pole does indeed have custom geometry. Huck to flat. Slacker. Permanently.
  • 1 0
 I could and I DID! Curtlo bikes, awesome builder that allows you to select your geometry.
  • 1 0
 Wow they still havnet fixed their spelling errors hours later. Embarrassing
  • 1 0
 Benefit of the doubt here, well played trolling.
  • 1 3
 Many on here are thinking way too simplistically. Sure you know you want a short chainstay lenght, but how does that affect something else... Or how does having a 210x55 instead of a 210x52.5 shock affect the geometry. How does positioning the pivot 3mm differently affect the shock curve and how does that then affect how it pedals up, or indeed down.
Doe changing the HT by 5mm make things actually better or worse... and why...

I think there's much much more to it than "oh i want 435mm chainstays and a 64deg head angle..",
  • 1 0
 Would your custom geometry be any different than what is already offered by the major manufacturers?
  • 1 0
 Most dont entirely understand how changing a flip chip changes their bike...I think that says enough
  • 2 0
 Grammer is a lost art o see
  • 1 0
 Gotta h8 it
  • 1 0
 How hard could it be? Just copy a known good bike and then your "custom" geo will be perfect.
  • 1 0
 How about just making the seat tube a little steeper on my 2017 5010 and 2021 Spesh Enduro? Please?
  • 2 0
 “How hard can it be?” - Jeremy Clarkson
  • 1 0
 Get over yourselves, we can't even ride the bikes we have to their potential.
  • 1 0
 Buy a medium 29er, because the top tube won't be bent as on the 27er and put smaller wheels on it and go shred.
  • 1 0
 I'm more concerned about PB grammar than my geo.... what the hell is going on here.
  • 5 3
 oonga boonga
  • 2 0
 here comes 40 hta
  • 2 1
 435 CS, 66.5 HA, 620 stack, 76 SA, 1200 WB
  • 1 0
 on an MTB? No. Road/gravel? yes
  • 2 1
 command-f stumpjumper
command-c
command-v
/
  • 1 0
 2m wheelbase 200 bb drop pls
  • 1 0
 Dunning Kruger AF poll results.
  • 1 0
 bring that shit to me bruh.
  • 1 0
 I would just combine my 5010 and v10 together
  • 2 2
 I wouldn't trust myself to pick suspension kinematics.
  • 4 0
 That's okay, the question was geometry.
  • 3 2
 @boozed: The geo could influence that? E.g. Changing chain stay length on a four bar design.





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