As I was close to finishing my hour of practice yesterday, I noticed on my 26” Nimbus muni the left side crank bolt was very loose. I came onto it pretty hard with the allan key to tighten it. Today after almost an hour it had backed off again. So Here are a few questions, Is there a torque setting I should put to it. Is just tightening it with the allan key and some blue loctite the way to go? Any thoughts why this happened and what is a good way to prevent it from reoccurring? Thanks
From this thread: “Use a torque wrench and take it up to 25 lbs. They should stay tight. Make sure the threads are clean, and use blue Loctite.”
Also if the ISIS spacers are too thick there could be some looseness in the spline and that would tend to loosen the bolt.
I have never used LocTite. I have no issues with crank bolts coming loose (except on my Schlumpf hub). JimT is right; if the spacer is too wide, that could create play in the interface which would loosen the bolt. You might check to see if the spacer is too narrow. Depending on the combination of cranks/hub/spacers, the crank bolt can be completely tight without having the spacer compressed / sandwiched between the crank and bearing. Using too-narrow spacers could really mess things up. I would first check to make sure you’re compressing the spacers. If that is okay, tighten the crap out of the bolts.
elpuebloUNIdo, JimT, I would think and hope the spacers are the correct size as they came new with the uni. The right side has remained tight so it is probably just a matter of following the directions as LanceB earlier posted. Thanks guys
If the crank was used when the bolt was loose that could cause some wear on the spline of the crank or axle and that would require a thinner spacer to make a tight joint. You can check to see if a thinner spacer is needed by doing this: The ISIS specification; there shall be a press fit connection between the male and the female tapered spline of about 3 to 6 mm, normally around 5 mm. In practice this means, when you attach your crank arms by hand, there shall be around 3 to 6 mm space between crank shoulder and spacer (if not: take a thinner spacer!). Then you tighten it till there is no gap between spacer and crank left to reach the proper amount of press fit and then up to about 40 Nm which will tense up the screw enough so that it can not loosen itself.
From here.
It is possible to have completely tight bolts but loose spacers. Make sure the the bolt and the spacer are tight. I bring this up because the ISIS interface caused a lot of confusion for me, early on. Good luck!
Thanks that’s good info. After I torqued the bolt, it and the spacer have remained tight. It’s only been used for an hour and a half so I’ll keep my eye on it.
Over the past two weeks of practice, each day I have been able to learn or do a skill better, gone up a hill further, or over a piece of terrain that I have not been able to do before. Not huge accomplishments but quite significant for me when they are added up. Also a good shot of confidence that there has been definite improvement each day. johnfoss maybe all the thinking about riding while I was off did help me. It took a couple of hours to get fully comfortable on the 26 again. Once I did things have happened quickly and steadily rather than in dribs n drabs. I’m looking forward to what I may surprise myself with tomorrow.
So after four hours of riding, the crank bolt is still tight. I guess it just needed the 25 ft lbs put on it, as stated not much leverage with those little allen keys. My gains are still coming along every day. I still must not be relaxing enough, because I do run out of gas after half a km on my dirt road. I feel that I’m sitting well and relaxed, then I get in some pot holes or on a hill and I can tell that I’m putting more weight on my feet. I do hold the seat with one hand while riding now, and I have been trying to get used to switching to the other hand. Once I get used to that I’ll work on both both hands holding the seat. Does it help to pull yourself into the saddle? I imagine it is just a matter of more saddle time than anything else.
I was thinking of getting another 26” tire that I could use equally for pavement and dirt roads. I have a Duro Wildlife Leopard now, it isn’t very good on pavement. I’ve been reading tire threads a lot, it seems the Felt Berm Master is about as good as one could ask for. I don’t think it is made any more though. Does anyone know of a suitable tire for this application?
Thanks
Maxxis Holy Roller looks a lot like that Felt Berm Master tire.
I have a Duro Wildlife leopard on my 24” Muni and I love it!
Lots of grip, bounce and roll-over capability.
For casual road riding I would not change it.
OK, It is a heavy tire but at firm pressure it is really not too bad. And who rides long distance on a 26” anyway?
What I like best about it is that it is insensitive to road camber.
I guess due to the nice round profile of the tire.
This year I have ridden over 600km on it, mostly on-road as I was preparing for a Climbing for Life event in France.
And I still love it!
- 1 on the 24’ Duro Wildlife leopard. I mainly use it for Muni but from time to time I also use it for riding around town to improve my skills (riding down stairs, rolling hops etc…)… Fantastic tyre!!
Quax1974, Interesting, for road riding what kind of pressure are you using?
I have a Duro Wildlife leopard on my 24" and at least compared to 36’er it is quite bad on cambered paved surfaces. I think I run about 25psi and maybe a higher pressure would be better.
Add about 10 more pounds of air pressure and try again. Those tires a definitely not made for road riding, but I find with enough pressure they handle road camber pretty well.
Ok guys thanks, I’ll pump it up more and give it a try on the road for a bit and see how it is.
For road riding I run my 24" Wildlife close to the indicated maximum pressure of 2.5 bar, which translates to 36 PSI.
I don’t know what is the max indicated pressure for the 26" though.
But as I mentioned; I find it handles camber really wel.
My 27.5 Maxiss High Roller on the other hand…
That tire just tries to thow me off the road 
Offcourse a n off-road tire it will never be as good as a dedicated road tire.
But swapping tires is not a lot of fun so for some causual riding I would not consider it.
And I’ve read in particular the Wildlife is horrible to get off / on a rim.
Alternatively if you consider longer rides you could consider getting a 2nd wheel with a road tire.
Swapping wheels is easier than swapping tires
Especially If you outfit is with cranks and pedals.
And for serious road riding you would like shorter cranks anyway.
I also read that certain KH rims make it hard to get the tire on/off the rim. Perhaps because the tire sits deeper into the rim.
Lots of interesting comments on this wheel question. Yesterday, as suggested I pumped my tire up to 35 psi, which is the max for the 26” Duro Wildlife Leopard. I rode it on the old piece of seldom used highway nearby. The highway is on a slight down grade, intermittently frost heaved along its .5 km length, as well as small surface cracks everywhere. The camber is anything but consistent, but it is a lot smoother than a potholed gravel road. There was a lot less rolling resistance with 35 psi compared to the usual 18 -22 psi that I have in the tire. It had a totally different feel to it balance wise as well, which will definitely take some getting used to. I don’t think I sat as well in the seat as I usually do. Once I reached the end of the old highway I then crossed a sideroad and the old hwy became a hard packed dirt road. I continued on this for another few hundred yards before I had an uphill upd. I’m sure a ride on a newer paved road would feel quite different also. This is about the furthest distance I have ridden so far in one go. I’m going to ride it some more with the tire pumped up to 35 psi. I want to get used to it before deciding on getting another tire or not. I do like what Quax1974 said about getting a whole new wheel with cranks and peddles. Then it will be a matter of choosing the right combination of wheel/tire and crank length, or another uni, hmmm.
You just need to ride with the higher pressure a bit longer and you will feel more relaxed. I noticed with the 36" that when the pressure is too low it makes it more difficult to mount because it adds more friction. Last year or so when I started adding more air in tires I thought it made the unis more twitchy, but nowadays I use that to more easily roll away. That is on the 32" and 36".
Today I have to fix my 36" tire as it sprung a leak. There is too much friction when all the air is out
Setonix, yes I agree, I need to ride it more pumped up to max pressure. I would have thought it would be harder to mount at higher pressure, as it would have more of a tendency to kick out from underneath. Interesting, I’ll take notice of how that works out, thanks.
While riding, sometimes more air is better, sometimes less air is better, no air is never better. 