Crank it up..

[seanryan]

So as a few of you may know ive had some issues with the cranks on my new mountain bicycle .
After some cranks falling off mid ride and much faffing etc, i took the bb mounted chain guide plate off and put the cranks back on just bb and cranks, fits perfectly no spacers required.
I will be putting these cranks on another bike but will be replacing them, i need a crankset that is slightly longer so it can accommodate the bb iscg plate.
What are my options, ps will be replacing bb aswell and the old cranks were xt hollowtech 2!

[Psycholist]

Unless the BB shell of your bike is way out of tolerance (Not 68 or 73 mm wide) you need to have one 2.5 mm spacer on the drive side of the BB for 73 mm and 2 on the drive side and one on the other side for 68 mm. If they're hollowtech II cranks do you know whether the pinch bolts were torqued correctly when you first got it?

If the BB is out of tolerance you might need to face it back to the correct length. I have the tools for this in my garage. Measure the BB shell first though. If it's exactly 68 or 73 mm then this is not the problem.

Are there any random washers on the BB axle of the crank? There shouldn't be.

There are no slightly longer crankset options for this if it meets the standard.

If the chainguide plate is more than 2.5 mm thick then the problem is with this.

[seanryan]

Front NDS to DS i had. crank arm, 2 pinch bolts, no plastic tab. NDS bearing cup. then (measured) 73mm BB shell. then 3mm BB mounted iscg plate,
then 2mm spacer (required as granny ring bolt holes rubbed off chain guide). then DS bearing cup. then DS crank assembly.

So technically a 5mm spacer has been added to the DS when all added.

I put this minus the chain guide into a 68mm bb shell and the end of the spindle is flush with the edge of the NDS crank arm.

If i were to remove the 2mm washer as the new cranks wont have the granny ring mounts would just the 3mm plate be ok or would i require a new plate/guide???

[seanryan]

http://www.pinkbike.com/u/seanryan/albu ... ly-cranks/
this is the assembly on the 68mm shell.
including the makes the shell seem 73mm in length by adding the 5mm.

Is the spindle protruding enough/to much, from the NDS...

Ps, sorry about the teeth marks on the arm. uncooperativity requires brute force...

[Psycholist]

On the previous setup you had 2.5 mm too much width on the axle, losing you that much spline engagement on the non drive side crank.

On the 68 mm BB shell if you're using the 2 mm spacer you have 5.5 mm too little on the axle. The end of the axle should not be flush with the outside of the NDS crank. The crank should be a mm or two short of this so the plastic preload cap that screws into the axle preloads the crank rather than just tightening onto the axle (Same principle as applies to the cap on the top of the steerer tube).

There are plenty of those spacers floating around in my garage if you want to do more checking anyway.

The photos don't really show anything useful to me in diagnosing the problem. Did you remove the crank with an axe or something?

From that photo the crank may be slightly too far onto the axle, but it's probably acceptable.

[seanryan]

So if i remove the 2mm spacer would that be suitable engagement??

Ill reassemble in the morning and show the initial problem and then with the 2mm spacer removed.. And will add photos to better show my problem.

Fairymount. pedalling from the truck to the start. very first run!! NDS crank fell off, put back on with allen keys, fell off half way down again, so went back to the van got my pedal spanner out of my bag and hammered it back on as it wouldnt go on by hand, it was either that or spend from 9:30 am till approx 4 sitting down the bottom waiting for everyone to finish! Lasted perfectly until i tried to pedal again yesterday in killaloe......

[seanryan]

This is the gap now with the 2mm spacer removed. Is that acceptable?
http://www.pinkbike.com/photo/10392528/

However the absence of the 2mm means that this gap is not sufficient for the guide to fit. thus will require cranks with no granny ring option.
http://www.pinkbike.com/photo/10392531/

[dannyk]

Say you should be able to get away with it without the 2mm spacer..., although what happens when you add the chainguide in again?

[seanryan]

The granny ring holes rubbed off the guide causing a channel marked into the guide!

Not bad now but if i rode with it for a while it would do serious damage.

Also when I put an 8 speed drivetrain on the NRS and spun the pedals the freehub made some funny grating noises, perfectly silent normally but with the stuff attached it rattled away!

Took the cassette off and there was a fair bit of wobble in the freehub body, is this normal or shout it be tight as a drum??!!

[Psycholist]

If it's a Shimano hub then a bit of play is normal. Grating noises are not a good sign though, so the freehub may be on the way out. This part is replaceable though, so not a big deal. Check to make sure nothing in the freehub is catching on the spokes or anything first though - it might have nothing to do with the hub.

If it's a Mavic wheel the grating noises are more common and also mean it's on the way out - replacement parts are available for this too and it's an easier but more expensive job than a Shimano hub.

Compare the prices with the prices of new hubs before committing to buy spares though, especially if there's a bit of grind in the bearings too. I recommend Shimano XTR - bikecomponents.de had them for just under €200 last time I checked ...

I also have a 120 click Superstar hub brand new if you're interested in buying that... It's a gorgeous hub and sounds like bees while freewheeling, but the aluminium freehub body wouldn't have played well with my torque output...

[seanryan]

It's a Sun-Ringle Ryde XMB hub so from what I remember previous owner didn't mention anything about replacing the free-hub. Just regreasing the bearings!

From my judgement it sounds like the bearings in it are bone dry and are rubbing off each other, coupled with a bit of play!

[seanryan]

The wheel and bearings are perfect it's the free hub body that's the problem!!

[Psycholist]

It being a Sun Ringle hub may be a large part of the problem here. They're easy enough to pull apart so you can open it and check it for cracked off bits of ratchet pawl in the drive ring. I've been waiting for a couple of months at this point for the warranty replacement on the snapped rear axle on my one though, so spares may only be theoretically available. Given the amount of wind-up in the freewheel mechanism under power I reckon the axle isn't all that's under built in these hubs. The bearings are known to be complete crap in these hubs too unfortunately, but lifting the bearing seals out and putting a bit of grease in will help them last another while hopefully.

[seanryan]

It being a Sun Ringle hub may be a large part of the problem here.

Was afraid you'd say that!!

How compatible are freehubs? Would Shimano fit sun/mavic/hope etc or are they specific to the brand?

To get at the free-hub, from my research, I need to go in through the NDS with a 11/12mm Allen key. Which I don't have.

[seanryan]

The bearings were done just before I bought them and they spin beautifully , really smooth!

[seanryan]

http://www.chainreactioncycles.com/ie/e ... -prod54490

This is the freehub i need, as you can see there is a kind of collar on the left thats inside the axle, this is unscrewed with the 11/12mm allen key.

[Psycholist]

Each brand has their own way of fitting freehubs and they're almost universally incompatible. The type you linked to is one of the rarest designs by the looks of it in that it copies the Shimano setup, where the freehub is a separate unit that bolts to the hub, with the freewheel mechanism entirely held in the freehub rather than at the interface between the freehub and hub bodies like most cartridge bearing hubs. I'd keep running what I have and pay a little extra later on to get this: http://www.chainreactioncycles.com/ie/e ... -prod40550 (Keep an eye out for deals on wheels too. Also bikecomponents.de is mostly cheaper then CRC before postage, so if you've a few things to get you can save money there) - the SLX hubs on my Anthem have surprised me in that they're still running without me ever needing to look at them, but the frame has fatigue cracked...

[seanryan]

That looks reasonable enough!
The freehub moves fine and quietly when help in my hands but its when i wiggle it side to side or let it freewheel in the bike with the drivetrain installed that the noise is very obvious.
Im sure i could still ride on it but id imagine it would give up sooner or later!

[Psycholist]

Since you don't tend to deathmarch you're probably not going to get stranded 30 miles from home on your own, so that's less of an issue...

[dannyk]

Yea I'd agree with that. Personally I'd just ride it until it gives up the ghost. Otherwise the list of things theoretically needing replacing gets endless

[seanryan]

Thanks lads think i'll just leave it and replace the whole thing in time!

Another question?
How universal are crown races?

[Psycholist]

No guarantee it'll fit if it's not from the same make and model of headset. This doesn't mean it won't get you home, but usually the sealing doesn't work correctly if the crown race isn't right, so the headset will die a lot more quickly.

[seanryan]

It seems quite snug I haven't push it fully down to the crown but it's contacting fully with the bearing and doesn't seem to add extra height to the stack...