Ask Pinkbike: Correct Shock Length, Tubeless for Gravity, A-Line Paralysis Tips, and Keeping the Bits Out of Your Goggles

 I'm personally curious about him not snagging that gravity rider of the year, or at least honorable mention, he certainly pulled of some shenanigans.

 im neutral but look at the results and stuff and you will see why josh won

 Not sure what race that was, but I know I've ridden races where it was so muddy that goggles were pointless: every rider came through the finish line with them off. At some point, you just can't keep them clear of mud, & you're better off just squinting through it.

 at one race i even stopped , took them off, and set off again... still won with 0.8 seconds lol

 I find for downhill races that are more like kayak runs that you can put your goggles around the chin part of your full face, they act like an extra guard to stop most of the flicking water.

 Some of the world cup racers are running roll offs at the races. This is a good way to solve the mud problem. A tear off system is also a good idea if your goggles are compatible and if they are permitted at the race.

 Someone watches too much Spongebob

 @Waldon83 Someone doesn't watch enough spongebob

 Some good weight training without using straps or gloves when handeling some heavy dumbells and barbells has def helped big time, also a bike with proper geometry for your size and body position to keep your weight back and on the pedals

 No simpathy for the guys who don't weight train and are running thin ruffian grips cause they think they look cool and its what so many others use when they start whining about their hands. Maybe if you wanked it every once in a while...

 ^ i had the same thought. i run ex823's on my DH bike and so far the og highroller is the only tire readily available in tubeless that i feel comfortable running on the rear. please maxxis, DH version of highroller 2 in tubeless.

 Don't ruin the marketing circle jerk! All these tires that were designed around normal rim widths are SO much better on wider rims because....ummm...well Pinkbike told us so. Jeez guys...

 "Almost no enduro racers run tubes as well"

 And also notable, alot of pros run 2.35 tires .

 I just went from i30 rims back to i25's because of tire profiles being less than ideal on the wide rims...I would say the only people running i30 rims for enduro are the few specialized racers running their traverse fatty sl wheelset..other than that there are very few companies making a rim over i25....The wide rim is awesome for going in a strait line but not so much for cornering

 I prefer 23mm rims myself just because of the profile it gives. 25mm works for me only when running huge tyres but 23 also works well for huge tyres.

 I'm going to use Kenda Small Block 8 2.35 on WTB Frequency i25 - TUBELESS.
While SB8 are not officialy tubeless ready, the man from KENDA told me to try it with the Orange sealant.
Also there are a tubeless-conv. kits that convert any tires/rims to tubeless system like Stan's or Joe's Sealant Conversion Kit on ebay.
That kits provide 2 molded rubber strips with integrated valves weighting 70 grams each( and other stuff.)

So, guys, did someone tried Kenda SB8 2.35" tubeless with some sealants/kits?
Is it necessarily to use that molded rubber strips(70grams!!!) or Gorilla type is enough ?

 Gorilla tape is not light, and a couple wraps around a wheel can often end up weighing as much as one molded rubber strip.

 ^id guess alot more than 70grams. 70 grams is less than 3/16 of a pound. if you're worried about that little added weight on a DH bike than you probably have a carbon frame, carbon wheels, carbon cranks, carbon bars etc. And if not than who gives a sh*t about 70g

 But the kits include also some spoke tape.
Is it enough only 1 wrap of gorilla tape ?

@ whitebullit
If you worried about that little added weight on a DH bike then yes I can agree with you.
But I did not mentioned DH bike.
My bike is at most for freeride with these wheels and current fork.
I mentioned Kenda SB8, they are not very DH, isn't it ?
And they are light: 120tpi 26x2.35" 680gramm
I like them because of fast rolling, pattern, lightweight and the price.
That's why I got them.

 @bikecustomizer, im not knocking your tire choice, just sayin you could drop 50x that 70g if you took a crap before riding. dont worry so much about grams, worry about getting the tires seated correctly. my DH bike has true tubeless and my trail bike has DH casings and DH tubes. id rather have a little extra weight and not have to worry all the time about getting a flat, but when i can afford it my trail bike is getting 823's as well. go for what works for you, regardless of weight, you'll be glad you did.

 One wrap of gorilla tape and stans sealant is fine for me on non tubeless ready tires

 Thats a 7.7 lbs crap.... Just saying you should probably get that checked out....

 @whitebuilt
"worry about getting the tires seated correctly"
That's one of the reasons I asked my questions.
But I also consider the weight savings. Just because if the weight can be reduced then I will at least try to do it (without crazyness of course). Especially if that weight is rotational.

"id rather have a little extra weight and not have to worry all the time about getting a flat"
That's another reason of my asking and this article.
There are a tubes of just 100g weight. 70g molded rubber strips vs 100g tubes....
Seems they are thin for rough staff but if not to go rough it's ok and there is no that tubeless hassle.

Also I like high preassure in my tires, usually ~3.5bars

@wydopen
Oh yeah, thanks! Now I'm full enthusiasm!
What is your weigth ? I'm ~85kg

 Im 190lbs Im running exo tries and riding very rough terrain...Ive only flatted once in the last year...if you set them up right you have nothing to worry about

 just for shits and gigs. im 200 lbs and didnt get a flat at all this year. booya bitches!

 Real acid?

 Aw fark, that make me laugh..

 I keep my goggles on the helmet in the "riding position" between runs, shake the possible dirt off before a run, ensure that the fit is perfect... and no matter how much I try to have it dirt free, there is always the occasional bit of dirt that gets in there. So I stop (after it got into my eyeball of course) shake the dirt off, resume run... and still manage to get dirt in there.

The guy who solves this issue deserves the physics nobel prize.

 Same thing here. The movement of the helmet obviously moves the goggle as well. I tend to have dirt penetrating the goggles on jump impulsion. Getting other goggles helped but didn't fix the issue 100% (note these were oakleys )

 Chips and brews for sweet DH. Got it.

 yes to hydration and grip size+hand size/preference. A-Line hands haha try garbanzo hands. now thats a bitch! oh and gloves help too if they fit properly, if they bunch up, or are too loose they can make things worse.

 My calves get crampy when I start to become chemically unbalanced...it's also an early warning system to prepare for a lot of HURT cuz it's COMIN' lol. This usually happens when I am dumb and don't mix my mix strong enough for a race level effort.

 This. I'm a career auto mechanic and my hands/wrists/forearms get abused on a daily basis, so I'm not as sensitive to arm pump from braking on downhill runs, but tweaking the bar position, controls, and grip size only helped so much with the intense wrist pain I was suffering after about a half hour of riding. Bigger grips helped a whole lot, but more was needed.

I found that in my newbness to dialing in suspension, I had too much compression and not enough rebound. Getting the rebound on my fork set up so it was slow enough not to pogo over big chatter (rocky trails) helped immensely. I just set it and forget it, so it works for the majority of my riding. Same with the compression, I get it close to where I want it and adapt from there, with plus or minus a few clicks as needed. Now I can ride for a few hours, until I'm pretty much spent, and no outrageous pain in the wrists and hands.

 ^2nd

Bad setup or poor performing forks (forks in need of a rebuild) lead to GI Joe hand. Make sure your forks are running smooth through all its millimeters and setup properly for how you ride. If you ride lots getting the forks serviced a minimum of once a season works wonders - even if you think they don't need the love.

 The end result of properly set up damping is being able to relax your grip on the bars. Relaxed is better. Relaxed will keep your upper body more fresh and the bike more under control.

 I'm also really surprised this wasn't mentioned. Keep a loose grip, let the bars float in your hands. Some of the best riding advice I've ever received. Helps to keep your weight centralized on the bike too! (you wont be leaning/pulling on the bars)

 Woah, I didnt know other people did this. I thought that i was the only one handlebar dancing in my cupped hands. This is solid advice, it's how I was able to ride my rigid single speed fast in my 20s. The whole bike was dancing under me. Just stop holding on so tight.

 Yeah i do this when i can remember but it gets really hard to do when your tired and weak.

 I actually never thought about trying to keep my weight more on my feet.Gonna try that tomorrow

 Aaargh the Manos Hands of Fate syndrome or, to the more holy, GOD (grip of death). If you're fighting with your bars then your bike isn't dancing in time with you

 The white knuckle death grip is my preferred style of riding!

 It depends how much of the anti-squat is in the shock tuning, or whether it is in the suspension linkages. Running a shorter shock will make the bike feel like it is further through the stroke than it really is, like if you set too much sag for instance. However, the shock will be running normally without the mushy feeling you get when you run too much sag. My mate ran a shorter than normal shock on his bike for a while because we had a spare one, and it worked pretty well, it slackened the bike up well and still had a nice suspension feel.

 Same drama however: if it's not shorter STROKE as well as shorter eye-to-eye, your suspension will travel farther at full compression, which can make things bash into each other just like something too long.

In my mind, it's more dangerous than something too long: you can change the angle of force at full compression on a shock mount doing this, which is less concerning at the top of the travel, but could be catastrophic in a hard bottom out: you might be loading welds instead of the mount.

 Good point, we didn't have an issue with this, he had a meta 55 at the time with plenty of clearance before the frame contacted itself. Would definitely be worth taking the air/spring out of the shock and cycling it to make sure nothing contacts before going for a ride.

 That doesn't really change the fact that the shock is pivoting farther than the frame designer took into account for the shock mounting, changing how the force is delivered to the mount(unless it's a model that's sold with a few different shock lengths: Specialized & Cannondale are known to do this.)

 In my case I'd be looking at a shorter eye-to-eye and shorter stroke, so no bashing into things.

 As for the other characteristics, It's going to vary widely based on the suspension type, the tune of that suspension type for a particular frame, & how much shorter you go.

Broadly, though, bikes are engineered to pedal well at certain point in the stroke, with a certain size chainring. you can make some bikes feel like crap just by putting the wrong size chainring on them. I'd feel better about trying it on a DH bike than a trail bike, & when I was considering doing something similar, I was going to stick with the same eye to eye, & just reduce the stroke.

After all, think about it: if you change the EtE & stroke by the same amount, if a 650b wheel is hitting the seat tube with the original shock, it'll hit the seat tube with the new one. So you have to shorten the stroke more than the EtE. Now you've magnified how much you're reducing the travel, because you're losing some by shortening the EtE(bike sits lower in the travel) & then losing some more by shortening the stroke(bike doesn't move as far through the travel before bottoming out.)

 I did this on my sx trail. shorter stroke, stock got 6.7 inches, with new shorter dhx air it got 5.9inches of travel, slackened the head angle from 66.5 to around 65 degrees. the bike felt like a new ride. it was perfect (and the rear was slightly more progressive)

 groghunter, I must have a unique frame then because the larger wheel is no-where near contacting the seat tube (or anywhere else) with the shock removed completely. The shorter shock would just put the suspension approximately at %40 sag of the original, so I'd need to run less sag.

 I was just using seat tube contact as a proxy for tire/frame contact, as it's the most common, but by no means exclusive, point of contact when you up wheel size.

Not sure what you mean by the wheel not contacting anywhere without a shock... is the frame contacting the frame, or binding at a pivot? something has to stop it from moving any farther.

 It is a FSR style design with a rocker mounted under the top tube, without the shock the rocker just swings up into the bottom of the top tube.

 forks that are too soft also make the problem much more severe

 can't see how too-soft a fork would hurt the hands. (maybe so if it leads to harsh bottoming) my hand pain only got more manageable when i softened my fork up. i would stand by that advice

 May seem counter-intuitive, but that's how it is. Going from a silver (the softest) to a red (medium) spring in my Boxxer helped immensely (according to Rock Shox, I should be running the silver). Soft suspension is almost never good. Now I can go on for much longer with no pain.

 i should have said its not soft spring, but making the rebound much slower that saved my hands. with slower rebound the fork tracks the ground better and does more work for you. there is a widespread misnomer about how rebound should be fast. i try to make it as slow as i can for the trail at hand. obviously it can be too slow & pack up but i play the slow side for best handling and less pain.

 You said that more damping is making the fork do more work, which is not true. The sole purpose of damping is to absorb energy, thus make the suspension work less (whether it be compression or rebound). Actually I like my suspension reasonably fast so it doesn't pack up. The more work the fork does, the fewer impacts are transferred onto your hands. Of course, fast and slow are subjective terms so we may not come to an agreement ;-)

 absorbing energy through damping is the work that forks do. how can you suggest that more damping is less work for the fork?! you seem confused. ill bet money that you will ride the same trail with more control with it slower. everyone knows you don't want it to pack up, but guys turn that info into "it should be fast" which is the wrong idea. several seasons at whistler pounding rocky lines have taught me this. i was a fast rebound guy too, until i got smart. I've saved myself and countless other guys from their sore hands & lack of control in the rocks by slowing down the rebound for them. at least in the case of DH on rocky terrain, although i can't think of any biking scenario where this isn't the case…
try it. its true. believe me.

 You're patronizing. I know how to set suspension up. I do not ride a pogo stick, it's my pet peeve, I always tell people to get their setup sorted if they do. I usually ride with my rebound damping at 50-60% of the adjustment range, which is fairly quick and very controllable. Of course you have more control with a well tuned fork, no need to explain that to me. But you ABSOLUTELY don't want your fork to be slow. It'll pack up, it'll be sluggish. It's dangerous.

Also, you're the one that's confused about damping. The more damping in a fork, the less work it does, because damping DAMPENS the work. Try setting your rebound damping and compression damping to 100%. It'll do much less work than a well tuned one. Put the adjustments at 0% and it'll be a pogo stick (but do much more work. I'm not saying this is better, just illustrating how damping affects suspension performance)

 "obviously it can be too slow & pack up" "everyone knows you don't want it to pack up"
after i wrote those things you still think you are educating me by explaining about packing up?? who's patronizing who? Ive literally been rebuilding and tuning DH forks since you were 7 years old, believe me i have a firm grasp of the topic and don't need help there...
you are still backwards and confused about the meaning of damping. not that i give a shit what you know or don't, i was just trying to be helpful to those who would benefit from reading the info cause i used to suffer from the same ignorance til i learned better. call any trusted suspension expert you like and try to get them to agree to your explanation of damping, ill bet money they will say what i have, you don't have to take it from me. happy trails in any case

 The whole point of damping is to absorb the excess energy stored in the suspension (specifically, the spring). Damping has nothing to do with absorbing bumps (although you seem to disagree for whatever reason). Absorbing energy from the trail is what springs do. Not dampers. Now reread the first two sentences of your 3rd comment. Something doesn't add up

 "Damping has nothing to do with absorbing bumps" ?!?!?! springs don't dissipate, they store and then return energy. The reduction in energy is the job of the damping system. (just for the record, please explain your understanding of "compression damping", and how the system isn't for "absorbing bumps", its bound to be interesting read.)

i read my 2 sentences again, nothing to report, they are still spot on. call Fox, or Rockshox, or any bike shop in the world that does fork work, and have them tell you the exact same thing, I've done all i can here

 Are you sure it's the derailleur? I had the same issue and it turned out to be a worn rear cassette. If you replaced either the rear cassette or the chain but not both at the same time, it may be causing the chain to skip, as the spacing between the teeth on the cassette gets worn at the same time as the old chain is stretching; when you replace one part but not the other, the spacing is different and it can cause it to skip like that.

I hope it helps. Had me pretty confused for a while trying to fix it, wound up replacing most of the drivetrain before I got the issue fixed.

 chain might be too long also pully wheels may be worn out

 First of all, thank you for your replies.
I replaced my chain and my cassette about 9 months ago. Everything worked fine for a few weeks and then, all of a sudden, the problem came back!
So I'm not sure if replacing the cassette and chain would help. I also got a new derailleur last September, because i smashed mine into pieces (don't ask how^^) and the same problem happend after a few rides.

 A lot of rolling resistance comes from the friction between the tyre and the tube as they move. If you do away with the tube you do away with this friction. You can 'spend' this saving elsewhere, ie, improving traction with lower pressure.

 It will roll faster on UNEVEN surfaces as as tires will compress more over small objects. This increase in tire flex will reduce deflection of the rider/bike mass center meaning better rollover performance.

 I know that quite a few pro teams have gone tubleless (GT, Santa Cruz, Specialized) but I would be surprised if all of them have. One needs only look at Aaron Gwin's run on his rear rim, when he peeled his tubeless tire off in a hard turn, to see that tubeless is still far from without it's own issues. There were at least a few Schwalbe riders testing the new Procore system this season and it seems to be a way to address some of the problems but it comes with a weight penalty.

 @whitebullit thank you for the term! I cant believe I had to read this far down the page to see the proper term. Its not imaginary, its a thing, and it involves blood swelling in a cavity (bring on the boner jokes) and pressuring the muscles in the forearm. I remember MXA did a massive article about it in the 90's. I think Kevin Windham or someone had to get an emergency surgery to drain the blood.

 Also, totally wrong comment to reply to. Oops!

 exactly, the form, the width and the material can all be relevant

 very true, I used to have pain in my hands, wrists and elbows, but when I changed to a handlebar with less sweep (from a 5 degree upsweep and 9 degree backsweep to a 4 up and 7 back) the pain just never came back. always try to take time to try different parts/set ups

 That's because with getto tubless the tube rim strip is not attached to the rim so it moves with the bead when the bead moves slightly off the rim. This prevents a lot of burping.

 Me too, my gf is physio and she does not understand why :-/

 She should loosen her grip a bit ;-)

 arm pumps a bitch. luckily coming from a moto backround i dont get it that bad anymore. but still, 6 hours of lap after lap will always have you hurtin somewhere.

 Crosstrain at the rock gym a few days a week: it'll hurt bad at first, but before too long, no more arm pump, ever. Plus climbing rules.

 Its not even arm pump though, Im the guy that asked the question and I used to ride mx so I know what arm pump is like... This is much worse!

 From my experience, running my brake levers just about as close to the bars as possible combined with running thin grips because of the size of my hands and positioning the lever body properly for one finger braking helped heaps. Running the brake levers close to the bar is good because your fingers don't have to reach very far for the levers. Reaching out a longer ways for the levers causes fatigue, which, coupled with the trail's obstacles and lots of runs, really adds up. On top of that, if you're running thick grips and don't have massive hands, you have to hold the grip tighter in order to stay in control because of the grip's wider diameter, causing more fatigue. Smaller grips, levers close to the bar and positioned well for one finger braking (i.e. don't have the brake touching/crazy close to the grip) will help a ton. Toss in well set up suspension, gym time and more riding to be in an ever better place.

 @Roguee, could it be deathgrip you are experiencing? you might not even realize it, your adrenaline could be taking over and you dont even realize youre squeezing the hell out of your grips.

 what handlebar are you currently using? Some are much worse than others. I've found the stock Specialized bars to be among the worst.

 i dunno about the lever thing - i run xt and one finger brake but get pain through all four knuckles/fingers. i have the enve dh bar if that means anything.

 I also had this horrible pain when riding and tried everything. Bigger/smaller/softer grips, bars, lever positions, fork settings. Nothing did help. What has sorted it for me is running wrist guards to support my wrists and probably most important keeping them straight instead of folding up. I use the 661's and the problem is solved! Never ride without them anymore

 I'm running nukeproof bars with slx brakes

 If you really can't find a solution (if it doesn't come from your brake setting, hand strenght, etc ...) have a look at the new Spank Components Vibrocore handlebars. The system works pretty well at smoothing the vibrations transmitted into your hands. The system has been used in MX for some times now (don't remember the name tough, it's some kind of solid jelly thingy you slide in your bar) that will absorb vibrations.

 www.pinkbike.com/news/spank-spike-800-race-vibrocore-handlebar-review-2014.html heres the article about it. You may find many ways to the same thing to your actual bar in the comments