Ask Pinkbike: Offset Questions & Full Face Suggestions

Apr 10, 2018
by Pinkbike Staff  
Ask Pinkbike Header

Here at Pinkbike we get inundated with all kinds of questions, ranging from the basic "Can I have stickers" to more in-depth, soul-searching types of queries like if you should pop the question or what to name your first child. Ask Pinkbike is an occasional column where we'll be hand-picking and answering questions that have been keeping readers up at night, although we'll likely steer clear of those last two and keep it more tech oriented.






Do I Want a Reduced Offset Fork?

Question: Pinkbike user @Shep77 asked this question in the Bikes, Parts & Gear forum: I have a 2016 Orbea Occam AM (140mm travel front and rear, 27.5). For 2018, they changed to a 150mm-travel fork and the head-angle went from 67 degrees to 66.5. The bikes which are using a low-offset fork for 2018, such as the Orbea Rallon and Transition full-springers, appear to have head-angles of 66 or less. Now that Rockshox has announced commercial availability of their low-offset Lyrik and Yari, I have been thinking about updating my fork to a 150mm, and going with the low-offset option. It might take an angle-set headset in order to get that last 1 degree of rake to really take advantage of a low-offset fork.

My question is, are there any other geometry measurements which I should look at before deciding this is a worth-while experiment. The bike currently has a Boost rear end, but a non-Boost fork, so it's difficult to upgrade wheelsets. This is another motivator to update the fork.


bigquotesThere's a lot of buzz around the concept of fork offset these days, but I honestly don't think all of it is warranted. Yes, fork offset does affect the handling of your bike, but putting on a reduced offset fork isn't always going to transform how it feels out on the trail in a positive way. It's important to focus on what performance attributes you're trying to achieve, rather than thinking that less offset is automatically better. It's just one part of the equation when it comes to bike geometry.

In my experience, reduced offset forks make the most sense on bikes with relatively long reach numbers. Bringing the wheel back towards the rider makes it a little easier to keep the front end weighted, which can lead to a more stable, locked in feeling while cornering. On the flip side, putting a reduced offset fork on a relatively short bike can make it feel like the wheel is tucking over too far in corners, which isn't what you want.

Let's take a look at your particular bike. Right now, with a head angle of 67-degrees and a 44mm offset fork, you have a trail number of 104mm. If you purchased a fork with the same travel but with 37mm of offset, that number would change to 111mm, and your wheelbase would be slightly shorter. For comparison, a trail number of 111mm could also be achieved by reducing the head angle by one degree. Trail affects what the steering of your bike feels like - in the most basic terms, more trail slows the steering down, and less trail speeds it up.

Still with me? I hope so, but it is easy to get overwhelmed by all the possibilities. If I was in your shoes, I'd start with getting a 150mm fork with the 'regular' amount of offset and seeing how that felt. If the bike still didn't feel slack or stable enough, then I'd put in that angle adjust headset. The Occam isn't that long of a bike – I think the benefits of the slightly longer wheelbase that will come from the longer and slacker setup will outweigh what you would achieve with a reduced offset fork.
Mike Kazimer


Forking
It's easy to get fixated on offset, but remember it's just one part of the geometry equation.





Enduro Helmet for Downhill?

Question: Pinkbike user @DirtJumpKitty asked this question in the Downhill: The Fox Proframe helmet has caught my eye for some time but I'm not sure if it's up to par for DH riding, even though it's "DH certified."

I just got into DH last year. I would say I'm an intermediate level rider and do have some good crashes (so don't want the helmet to break on the first fall). I mostly ride the Blue Mountain Bike Park (Ontario, CAN) and planning to go to Whistler this year.


bigquotesFox's ProFrame helmet is certified for downhill, which means it complies with normal helmet regulations plus an additional safety test on the strength of the chin bar. The ProFrame was designed around enduro racing use and has huge ventilation and no foam or mesh in the chin guard to help heavy breathing to get maximum airflow.

If you are purely riding downhill with lift access in a not too crazily hot location, I would not recommend the ProFrame. There are two trade-offs of the design which are big pro's for enduro, but con's for pure downhill and bike park. Firstly, the huge ventilation leaves you more susceptible to incoming branches or sticks, and even though it passes the safety test, an unlucky crash might leave you with a pointy rock in your head. Secondly, the open chin bar area will eventually leave you will a mouth full of dirt, dust, mud, flies, wasps and whatever else is out there. If you are purely in the park just go for a full on DH helmet - you can cool down on the lift.

The major point you did raise in your question was having multiple crashes as you are a beginner rider – all helmets should be replaced after a crash. Even if they look fine on the outside, the EPS foam which absorbs impacts could be compressed leaving you with less protection for the next crash. There is only one exception to the rule I have found which is POC's Coron helmet which uses a multi-impact EPP foam but is a premium product at €500.
Paul Aston

Theo Galy charging through the rocks on stage eight. Theo rode to fifth place on the weekend.
Probably not ideal conditions for the massively vented ProFrame helmet.




Have some unresolved tech questions? Jump in the Pinkbike Forum and we'll look to answer it for next time.


85 Comments

  • 156 1
 Can PB do a poll on how many people actually replace their lid every time they crash?
  • 90 1
 There's crashing and there's crashing. I've replaced a few over the years. I think generally you know when the impact is big enough to warrant a new lid.
  • 6 0
 pretty sure they did a few months back...
  • 17 0
 Just because some people don't replace their helmet after a crash doesn't mean you should follow suit
  • 6 4
 Ive had a few big knocks but I've only replaced my helmet twice and thats after cracking them. Being a student too I don't always have alot of $$ laying around to buy a new helmet just because I hit my head.
  • 6 2
 Shit... I wear a dot certified mx helmet from oneil and things a beast.. then again I havent seen any "serious" crashes with it.. mostly roll overs or doing head slides on it. I think if anyone replaces its the cat 1 guys with the single impact carbon helmets.
  • 32 2
 @icedemon05lrb: I'm one of the cat 1 guys with a carbon MIPS helmet, and pretty much replace them annually. Even without any big crashes, a year's worth of small getoffs usually leaves a helmet looking worse for wear and I'd rather spend $350 a year than have cognition problems later in life.

You only get one brain, and damage to it can't be fixed. Don't be cheap about your helmet.
  • 2 0
 @harveymurphy199: Bontrager will send ya a new one if it's within a year. FYI
  • 1 0
 It's a bit harder to tell with the Smith helmets and the aerocore construction. I did crash mine - but not as bad as several other crashes where I knew it was time to replace the helmet - esp when you can see cracks in the foam. I still use it sporadically for lighter duty - not that you can predict when you may crash - it could happen on a beer run a block away...
  • 1 4
 @CaptainBLT: I agree.. thats why I dont buy anything not DOT certified. Not worth it. Carbon doesnt save anything.. just makes the impact on the shell lessened. HAve you seen the difference in padding? lol I had a tld carbon flame... loved the look but not the safety after hitting a tree on the wc course in Angle Fire.
  • 5 2
 @icedemon05lrb: you're one of those goons riding in a moto helmet? Damn, I wish I had your confidence.
  • 3 0
 Kali replaces them for free, you just pay shipping. I've only done it once but it was painless and cost me like $12
  • 8 0
 what....you're supposed to replace your helmet after every crash? must have forgotten.
  • 3 2
 @CaptainBLT: you willl spend 10,500 dollars on full face helmets in the next 30 years of your life then
  • 1 0
 Well every time you crash AND hit your head ! Otherwise that'd be a bit ridiculous right ? In that case I guess I do but usually i just slide on my side or stuff like that and my helmet don't touch the ground so why would I change it ?
  • 2 1
 @icedemon05lrb: No doubt, I do the same, just grab one of those beasts from the garage for lift access days, screw fashion, Live to Ride another Day!
  • 1 0
 i normally replace them after either a bad crash, or 2/3 years, i have broken a fox metah and a tld d3 carbon. other than those hits, it's only a few scrapes, most crashes ou either slide/role around, or don't even touch your head nowhere
  • 1 1
 @CaptainBLT: You must be a dentist
  • 2 1
 If I would replace my helmet after every hard crash, it would have meant a new helmet pretty much every ride back when I started out. I think I replaced it every now and then when I realized there was no good spot on it anymore to crash onto. It was only that article by Danielle Baker a year (or so) ago that made me realize how serious a concussion is. I've had my fair share of concussions but I've been diagnosed with ADHD too so I hadn't realized that lack of concentration could be caused by old concussions too. Either way, I'm crashing a lot less in recent years so helmets last a bit longer. Not be a neuro-expert, it is hard to see through all the marketing, pseudo-science and real science. I decided to go with the cheaper helmets though. A crashed a few weeks ago and cracked my 25 euro On One Enduro (open face mtb) helmet, bought two helmets to replace it. Wrecked my POC Receptor Flow (dirtjump) helmet last week, thinking of getting something similar from Abus for about half the money. If companies are pushing the limits of lightweight and much ventilation then yeah at some point I expect the expert companies to do a much better job. But if I'm getting something with good coverage, no sharp angles to get hung up onto (to introduce rotational loads) and it passes all the certifications then I expect it to be decent. It appears like more money gets you lower weight, clear coat over carbon and better ventilation. But a more expensive helmet may also make me less eager to replace it after a crash, which may actually be the biggest risk. What I see in more expensive helmets of course is that they also introduce other safety measures like a slip plane (MIPS or similar). Tests I've seen are done with a bald dummy. I'd be interested in how it compares when using properly hairy dummies. I don't think I've ever seen Pantani wear a helmet (though I must admit I've not been paying close attention). So yeah, I'm not entirely convinced I'd benefit from the slip plane. And POC is not convinced of the benefit of a neck brace, so we'll call it a draw. What I do know is that it makes sense to replace a broken helmet and for them to be that disposable, they need to be cheap. Unless local brand Egghelmets releases an adult line of helmets too. I also want a helmet with a mohawk, horns and flames. You can never be too cool.
  • 3 0
 @honda50r: My livelihood is dependent upon my brain, which is a deliberate choice. When I was younger I worked in forestry, but had a riding injury that put me on crutches for 9 months and unable to work. I had to choose between changing my career or changing my hobbies. I retrained for a career in engineering and I have a much better appreciation for protecting what's important.

I just had a similar leg injury last year with a similar recovery time. This time, the only consequence is I can't do my favorite hobby. The last time was life changing, this time is mildly frustrating. Protect your brain, you need it for everything.
  • 2 0
 @dirtmiester: I'm not saying that everyone should buy helmets as often as I do or for my budget. But they should always wear a helmet, and it should be a priority to keep that helmet in good condition. Head injuries can be devastating in one instant, and even "minor" concussions really mess you up later in life.

Go ask a someone experiencing early onset dementia if they would pay $10,500 to have more time with a sharp mind. Then ask their family. Then reconsider the value of a good helmet.
  • 2 0
 @CaptainBLT: Well yeah I absolutely agree the quality of the helmet is important. I just don't think it necessarily correlates with the price. Ever since I started back late 2001 the open face helmets I bought had extended coverage in the rear. I didn't need the lightest, best ventilated or most stylish. I just wanted the best protection and more protection at the back of head seemed to make sense. I'm no neuro scientist though. I can merely try to follow their logic to judge whether it makes sense or not. When I smashed my first full face (bicycle) helmet, I replaced it with an MX helmet. I thought bigger helmet, more material, better protection. I only later learned that it doesn't quite works like that. Either way, what I'm seeing now with the way helmets are marketed it is still about the number of vents, weight, "carbon", style and maybe some features (buckles, adjustments etc). They don't add anything to the safety of the helmet, just to the price. In fact, if the high price makes me more reluctant to dispose of the helmet when it is cracked, it (hence these features) are only reducing the safety in a way. The way it is now, I go for the helmet that has the certifications, seems to have good coverage and fit and I choose the color I like. If I have a good smash and notice a crack, I remove the small parts I want to keep spare (pads, peak) and the helmet ends up in the trash. Just because I'm replacing a POC helmet by something from Abus doesn't imply I'm lowering the safety standard. Abus may not be the most flashy brand around or even associated with high profile athletes, but it is still a brand dedicated to safety and security and I don't expect anything sub par from them.

That said, I think out of all my concussions I think there was only one bicycle related and I was wearing a helmet. The other ones were stupid stuff. No alcohol or drugs involved and not even something where I should have been wearing a helmet. First was when crossing the street (aged 9) and not paying proper attention. I got knocked down by a car. Another one I can recall was on my paper round (aged 16). I was always running and jumping down the stairs. This time apparently I jumped a tad (from) too high and hit my head against a wall above the stairs. Most recent I can think of is that I have this special "ability" to laugh so hard and for so long that eventually I faint. Usually I notice and try to at least sit and calm down. Occasionally I drop down. This time I dropped and hit my head against a heavy flowerpot that didn't give way. Again, no drugs or alcohol involved. Ever, actually. Ever since, my girlfriend gets quite nervous when I'm laughing for more than a minute and pushes me down before I can drop Wink .

So yeah, I'm wearing my helmet and replace it when I should. But unfortunately that is by no means a guarantee that I won't ever suffer another concussion. And I'm not saying that proudly, because concussions definitely suck big time!
  • 3 0
 I been rock in my D3 sence 2011 in not as think as i smart I am
  • 31 1
 Multi-impact protection means that your head is protected when you crash and your head bounces off the ground several times in a row. It does NOT mean that you can have several big crashes and still keep on riding the same helmet!
  • 4 9
flag meesterover (Apr 10, 2018 at 13:43) (Below Threshold)
 But if you are hard-headed, it is a moot point (to even wear a helmet) brah.
  • 3 0
 Kali MacDuff claims exactly that. "... no more crash and trash..." but I don't know where and if you could ever actually buy it...
  • 5 0
 I wish MIPS stood for Multi Impact Protection System but our expensive MIPS helmets incorporate Multi-Directional Impact Protection System technology.
  • 24 1
 Sam Hill you legend!
  • 10 3
 Proframe is sweet. Just bought it for my kid. And price isn’t killing either. If you don’t race on DH tracks, it seems to be the best. But as far as lift assisted riding goes, dress up to the occasion and buy a proper FF for FFS
  • 24 0
 When I went OTB wearing a FF not OF riding DH I thought WTF, but then I thought FFS thank god for the FF FTW for DH IMO (BTW it’s a D3)
  • 1 1
 Good Morning Vietnam!
  • 9 0
 I have cwashed the sim hellmitt a few tims with no not even one.
  • 7 0
 gwood fer yoo ser!
  • 6 1
 Coming from racing motocross I know how important it is to replace after a good impact. Also if you have a $2.00 head buy a $2.00 helmet. Personally I value mine and buy top of the line and replace after a hit
  • 3 0
 I have one rule: Never buy a used helmet or a used pair of gloves (eww). I don't scrimped on one of the most important equipment for mountain biking: your helmet. "This will do" or "This looks ok" is not ok. It's not you who's going to take care of yourself when you have a severe concussion. It will be your family. So spare them the anguish and buy a decent helmet.
  • 2 0
 This reduced fork offset thing has been around for far longer than the trend would have you believe... every Pike I’ve gotten thru QBP for the last 4 years (2014 26”, 2016 27.5”, 2017 29”) was available in a reduced offset, which I very willingly bought
  • 2 0
 Sounds like you're due for a Pike 32" this year or next!
  • 1 0
 Back in 2008 I demoed a bike with a 160mm lyrik on it. It felt like I was on top of the front wheel. Got back to the shop and shared my thoughts, and the owner let me ride the same bike (his bike) with a 180mm 66 and a fair bit more offset (don't recall exact numbers). One quick spin around the parking lot and I was sold. I ride that bike quite happily for years until I cracked the frame. Point is it goes both ways depending on bike, Geo, and preference.
  • 2 0
 The older POC Cortex also used EPP and can probably be found 50% off or so at most places that would still have them in stock if you didnt feel like forking out for the latest and greatest.
  • 1 2
 But Cortex was a noodle.
  • 2 1
 My Mondraker Crafty with a 44 offset has more stable steering than my friend's Crafty wirh 51 that is a bit more lively. It isn't day and night but for sure there is a difference between the two of them and it comes down to personal preference I suppose.
  • 1 0
 Just picked up a Bell super DH, burly. But I’d still never wear it on proper DH trails. Vents and coverage leave it suceptible to intrusions.
If there’s some serious consequences, put on the right gear. One brain and injuries to it are permanent, take care of it.
  • 4 0
 "You can cool down on the lift"- @paulAston
True Truth Sir.
  • 5 0
 Not always. Sometimes there is no wind and the sun feels like the ozone hole is directly above you. Or you are imprisoned in a saundola that has one tiny little window/air vent for which you are desperatly trying to stick your face through, gasping for air like a refugee in the cargo hold of container ship.
  • 1 0
 @Boardlife69: yup - i remember 2 years ago in a 30 degree les arcs, my nice white bull super 2r I wore all day except to eat lunch. my friends with the cheap black 661 downhill helmets were removing them at every opportunity and looked like sweaty drowned rats
  • 4 4
 I don't think I would trust the Proframe especially for downhill racing. Two days ago I went OTB while racing DH and cracked my carbon D3 on both sides of the chin bar, the very front and at the back. The Proframe may be Dh certified but its a mental thing, it just doesn't look like it would handle some of the bigger hits. I also have learnt that if your unsure about your helmet standing up in a crash, thats gonna play on your mind, and you'll probably crash. I don't think i would trust some of the detachable chin bar enduro helmets either but thats another story.
  • 18 4
 i crashed in a D3 and cracked the helmet. did the same crash in a proframe and no crack. theyre called anecdotes
  • 30 0
 @krazieghost: am I the only one who laughed at "the same crash?"
  • 9 0
 @saboob: Uhh testing? Usually I try three or four helmets on and throw myself down the same stairs to see which one is more comfortable in a crash!
  • 2 1
 Fell in a berm at Windrock. Pro-frame chin bar broke in 2 places, helmet itself cracked in 4 other places. I had a concussion and went to the ER for amnesia. Overall I was OK and I believe the helmet did its job as good as it should have. The Pro-frame is awesome for gnarly hike a bike type riding but definitely would not recommend for lift parks. I bought a replacement for the record because I feel like it should have cracked/broken given the amplitude of the impact.
  • 1 0
 Seriously though, whats the difference between changing the fork offset a few mm and changing the head angle by half a degree? Is there a difference? I would really like to know...
  • 1 0
 Think head angle vs wheel base. Slacker bikes can shorten/manage their wheel base while still retaining the benefits of a slacker angle. You can adjust trail/steering, optimizing for different geos. I know just about anyone could explain better than I... this is also discussed in the article. Of course a half degree here and a few mm there, prob not that big of a deal
  • 3 1
 I brome my Proframe completely in half. Was the 3rd and final time it saved my ass. When it breaks in two, bin it.
  • 25 1
 Nah, loads of life left in it. Gorilla glue FTW.
  • 4 0
 Can I have stickers?
  • 6 7
 So, you reduce fork offset to reduce wheelbase on the bike with a very long reach. Why not just have a bike with little less reach so your front wheel is properly weighted without creating a new "standard"? WTF?
  • 5 0
 Long reach will suit some riders, especially taller ones, as far as body position goes, but it can make the bike less manoeuvarable because of the wheelbase. Less fork offset allows the same head angle but shortens the wheelbase without making the rider feel cramped on the bike.
  • 12 2
 I drew this long time ago.. I guess it’s still relevant
www.pinkbike.com/photo/11655861
  • 5 2
 @metaam: I feel like the change to wheelbase via offset is a little bit overestimated. A Large Kona Process, for example, has a wheelbase of 1216mm. changing a fork from 44mm to 37mm offset is only reducing the wheelbase by 7mm of 1216mm, or 0.6%. Not really a big change.

More than anything, offset changes affect fork trail, and therefore the stability of the bike at speed (at the cost of steering response).
  • 5 1
 Fork offset is a steering feel change above all else and a geometry change as a very secondary effect. It corrects steering feel for slack head angles and large wheels. Motorbikes use it extensively to control steering feel because high grip tires on pavement will exaggerate the impacts of offset and trail.
  • 1 0
 @RoboDuck: yes. Just think JB the same thing. Offset shouldn’t be used as a way to increase wheelbase, rather how it affects steering input. I wish writers would stop mentioning wheel base numbers and trail...
  • 3 2
 Thanks for taking the time to answer some of these questions - it helps everyone learn something new!
  • 3 1
 Yeah that offset advice is money, been wondering the same thing and that's the clearest explanation thus far of fit and compatibility.
  • 1 0
 Yeah!!! It was crickets chirping on my original post. I like MK's approach, which avoids me spending a bunch of money and accidentally making the bike less fun to ride, rather than more.
  • 3 2
 Are there plans for an app version of the site? For example the Newschoolers app?
  • 1 1
 Buy an Arai moto helmet - might not be the lightest, but it's safer than any helmet you could find on this page or comments
  • 5 0
 Safer if you go into a tree at 40mph but you're not doing that on a bike? Moto helmets are designed for higher speeds and if you go down at 20mph helmet will stay undamaged and all of the impact force will go straight to your head/brain while a DH fullface will brake or will get damaged (EPS/EPP will compress) and thus absorb impact instead of your head. On whole DH WC circuit only Minaar is using a moto helmet.
  • 1 0
 @vid1998: ^this, exactly.
  • 1 1
 I sometimes even use full face for enduro
  • 4 0
 Some enduro events require a FF on all timed segments, and a helmet of some kind (carry extra or removable chin) on all transfers (CES Mammoth for example). You can get DQ'd for wearing your FF like a hat on transfers. I just go FF all the time, it's not too hot where/when I ride.
  • 1 1
 @endlessblockades: Panama is too hot and our trails arent anything like other countrys, we dont even have trail parks so we mostly use full face for protection because of the amount of rocks on trails
  • 1 0
 @sasso90: I didn't recognize the flag - it must be brutal in the jungle there! I went through the Canal twice on an old freighter when I was a kid decades ago. Carry on!!!
  • 3 3
 get a Bell SuperDH.....just works, and not comparable to Super R..
  • 2 0
 I must say that I saw it in person and it’s sweet. Seems better than Switchblade 2
  • 1 0
 Agree... Super DH is the best helmet I've put on my head. More comfortable than Proframe, cooler than Switchblade, and still DH-rated. It's good that it can do everything because it costs as much as 2-3 helmets. Smile
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