I would usually run a Rock'R2 on the rear at around 28psi. The HR2 EXO I have on now I try to keep at 30psi, and I still get some rim-strikes on a few of the extra-pointy-rock trails around here. Front Rock'R2 I usually run 22-25psi.
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I'd say just put more air in your tires. How much you weigh?
Those michelins are still pretty damp at higher pressures. 22psi front is just asking for trouble IMO.
You got like 25lbs on me. You're destroying tires because you have no air in them. If you really get all smashy smash, 35psi in the rear will still deform enough to grip for you. Yeah man, you weigh more than me and run lower pressures. it's gonna be a bad time
I suspect I don't ride nearly as hard as yourself. :cool:
That said - I shall consider bumping up rear pressure when riding those prickly trails...
I probably also need to come to terms with the fact that I'll probably never be 180lbs geared up again, and act appropriately. :D
I know I'm going to curse myself, but I've only had one flat since I switched to the Rock'R2s (summer 2016) - and that was definitely due to low tire pressure (I forgot to check prior to a rocky ride).
Dammit. I'm surely going to get a flat on my next ride now. :mad:
Brakeside crank somehow came loose and fell off while riding home from work today. How the hell does that even happen? The crank socket (or whatever the correct term is) deformed a bit in the process, can I safely reinstall it and keep using it?
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You'd be amazed at how often I've seen that. Crankbolt gets lose from vibration, then slowly starts to back out from crank pressure (on square taper the taper itself tends to push the crank outward over time when the bolt isn't tight.) Eventually it gets so far out it wobbles, which bends the metal on the inside edge of the crank. Bad on a ride. REALLY hilarious when it's your brother and it comes off when he's in the middle of a sprint finish in a race. Good times. ... Was that outloud? Anyway...
Sometimes you can put it back on, tighten it up, and it'll work. Depends on how much positive contact area you have left on the crank to interface with the taper. If you put it on and it's at all wobbly, it's done unless you try to ghetto fix it (more on that in a sec.) One issue with trying to tighten it up to take out wobble is that if you tighten it up too much you can split the crank. Which is bad.
Anyway, if it doesn't work and you want to try the ghetto fix, you use strips of aluminum foil to shim the areas where the crankarm bent. It's not easy, or in any way recommended, but I know of bikes fixed that way that are still being happily ridden 10 years later.
But it's your crank. You have to gauge for yourself how much you are willing to risk with any of this stuff, and how bomber it feels when you are done reassembling.
Because my brother who lost it field sprinting? Heavy damage man. To more than just him and his bike. Was spectacular.
Kinda weird for a commuter maybe, but not unheard of. Had it happen a few times on a mountain bike.
Put it back on and crank it good and tight. If there's no play, ride it. If there is play, ride it carefully.:D
If it keeps loosening, you could try some blue thread lock on the crank bolts, but if it's too fudged, you'll need to replace the crank.
The good news is that replacement square taper crank arms can be found for around $10 used, or $20 new.
Put it back on and it seems solid enough to ride tomorrow. Just to be safe I'll see if I can get a replacement cheap somewhere. I replaced the cranks on this bike in February and I was lucky to get the bolt out of the old cranks, hence my surprise. My only other experience with square taper is on kids bikes.
What length is it?
I might have a line on one.
If it loosens again, or just doesn't tighten enough, try greasing the tapered spindle and tighten the crank bolt A LOT.
This will probably split the crank arm.
Beece is on point. Additionally, some green loctite in there with the aluminium foil might help - but I'd recommend replacement - you ride the shit out of your commuter.
You've got it reinstalled. It'll feel good, but you won't really know until you put a few miles on it. Usually when they get deformed like that they're done.
I'd be sure to bring an 8mm with you tomorrow on your commute. Check tightness when you get to work. If it loosened up again you'll have to replace it. NDS square taper crank arms are cheeeap.
^^^ Splitting would put an end to it... I figured it'd just distort the area around the square hole in the crank enough to tighten it up a bunch.
FWIW, it is not recommended to grease the taper on a square taper BB because of likely overtightening.
we had set of raceface turbo cranks on juniors Holeshot hard tail which used to creak a lot, so on advice of a train locomotive mechanic we got a Loctite product for retaining sleeves and bearings, cleaned the spindle & crank, apply product let it cure the creak went away, it was like gluing the crank on with epoxy
except then he snapped the square taper spindle so we didnt have to worry about creaking, then he broke a couple more square tapers, at that point he was good enough to pretty much break them on command
so we got him a full suspension with octalink crank & spindle so he didnt break anymore spindles,
Instead he broke the frame in half...
BB spindle looks fine?
NDS square taper arms are super cheap:
Sunlite Allow Low Profile Left Crank Arm w/Square Taper, 170mm, Black https://www.amazon.com/dp/B000AO5J20..._W-3YDb6XF05KK
I’ve never had to use Loctite on any of my square taper crank bolts ... have always used grease (on the bolts, never the spindle) and torqued to spec. But then again this was old Ultegra stuff before the Octalink self extracting stuff came out.
Made it to work alive. Felt OK and kept a close eye on the spindle. The bolt took about a quarter turn at the office. Replacement crank arm has been ordered, but with frequent torque checks I think it's OK to ride temporarily since driving to work is the worst. No balls-out green light sprints for the time being.
just be careful on the road gaps cuz when the spindle snaps the opposite pedal will come around and put a pedal imprint in your calf and i'm not sure how he managed to stay upright
Is there a temperature range that you stop riding full suspension bikes, assuming you have an alternative to ride? In my case I have a 2019 Patrol NX- Rockshox Yari RC up front, RS deluxe RT air rear. (a developing newb’s) Concerns are premature wear and suspension pressure finnicks
Nah. You may notice some change in performance due to oil viscosity increasing, but you aren't hurting anything.