Question about Truvativ Stylo SS cranks and related drivetrain questions

[foofighter]

Ok so i notice that my SS has a weird grinding noise when i'm pedaling on the downstroke. Also when I spin the crank backwards it's spins freely and then tends to bind up.

So I took the crank apart cleaned everything out all the dirt and grime etc. I noticed that on the non-drive side there's some wear on the rubber dust cover. Was/Is there a washer that goes between the crank and the BB's surface? So that's question 1.

I cleaned all that up and put the BB back on tightened down the crank bolt and spun it and it seems to be fine, no tightness in any portion of the revolution. So it may not be the BB bearing after all?

I examined the chain next and went through link by link and noticed that there were a couple that seemed a bit tight and didnt want to pivot so much...this might be the culprit.

I put the drivetrain back together and took it for a spin and noticed the sound still, now i'm wondering if it's my chainring could it be slightly bent may be causing this sound and I go through my pedal stroke? I looked at the chainring again and tighten down on the 4 bolts and did notice that there were a couple that had loosened up a bit that i tightened down again.

So based on all these variables...what would your guess be? I think the cheapest would be the chain and then replace the chainring next...

thoughts?

[dstepper]

I could not keep those cranks from complaining...chainring bolts always coming loose. For SSing get a good set of Eno's or Middleburns and don't look back.

Dean

[Rob]

Could you see any bent/worn teeth on the chainring? I'd either replace the chain, or see if you can work out the stuck links, since you already know of one problem that needs work.

What kind of chain is it?

Is the wheel centered in the dropouts good?

[duke777]

How old is your crankset and BB, the BB might of gone bad.

Also check your chain, certain sections could have stretched from hammering. Make sure your chain tension isn't too tight, it need to bounce up and down just a little.

[foofighter]

Originally Posted by Rob

Could you see any bent/worn teeth on the chainring? I'd either replace the chain, or see if you can work out the stuck links, since you already know of one problem that needs work.

What kind of chain is it?

Is the wheel centered in the dropouts good?

dont see any visible signs of any bent teeth on the chainring. I'm using the SRAM PC-1 (the SS chain) and the wheel is centered.

Originally Posted by duke777

How old is your crankset and BB, the BB might of gone bad.

Also check your chain, certain sections could have stretched from hammering. Make sure your chain tension isn't too tight, it need to bounce up and down just a little.

I think the cheapest would be to replace the chain first. the non drive side BB seemed a bit more "gritty" when i was examining it but underneath the rubber dust cover was just nasty dirt that i cleaned and it appeared to have gone away but spinning it with your finger is different when you are putting force down on it.

[duke777]

Originally Posted by foofighter

dont see any visible signs of any bent teeth on the chainring. I'm using the SRAM PC-1 (the SS chain) and the wheel is centered.

Definitely replace the PC-1 to something better. I tried the PC-1 and it kinda gave the same problem you had. Try one of the BMX racing chains Tani carries. It's not expensive($27?) and very strong. I'm 200lbs plus gear so far they held up much better than all the other chains I've tried.

How's your chain tension? Make sure it's not too tight.

[klutter]

First off, you have a 29er, so you need to get used to these sort of problems (or as some 29er riders may say, those aren't flaws, those are FEATURES!).

But all kidding aside, you mentioned that the chain seems to bind at some point when you back peddle. When it binds, take note of the position of the pedals. Does the binding occur when the pedals are in the same position? If so, you might have a case where the chain ring isn't perfectly round (this is typical for most chain rings). As you spin the pedals around, the chain will begin to bind when the radius is largest....or something like that. In any case, try to position the pedals so that the chain begins to bind. Now, adjust the rear sliders to provide a little more slack. This way, your chain will no longer bind. Lastly, maybe the grinding noise is associated with this binding. Hopefully this will fix both problems.

[foofighter]

Justin, it's in the same position...thanks for describing that as that's what i was trying to articulate but it didnt make since. I think you maybe right that it's not completely 100% round

Originally Posted by duke777

Definitely replace the PC-1 to something better. I tried the PC-1 and it kinda gave the same problem you had. Try one of the BMX racing chains Tani carries. It's not expensive($27?) and very strong. I'm 200lbs plus gear so far they held up much better than all the other chains I've tried.

How's your chain tension? Make sure it's not too tight.

they sold my buddy some THICK ass chain...it's hot but dam it's heavy but it works great for him. It was packaged like a high class box of cigarettes KOOL was the brand?

Chain tension is fine not too tight but after what Justin said i may just back it off a wee bit.

[klutter]

Check out this Sheldon Brown article

http://www.sheldonbrown.com/fixed.html

(scroll down to the chain tension part)

This is a better explanation on how to approach the chain tension issue, of course you've got the extra degree of freedom of being able to move the sliders back and forth.

[duke777]

Originally Posted by foofighter

Justin, it's in the same position...thanks for describing that as that's what i was trying to articulate but it didnt make since. I think you maybe right that it's not completely 100% round

they sold my buddy some THICK ass chain...it's hot but dam it's heavy but it works great for him. It was packaged like a high class box of cigarettes KOOL was the brand?

Chain tension is fine not too tight but after what Justin said i may just back it off a wee bit.

The one I got was in a small shoe polish looking can.

It's all but impossible to bolt the chain ring on dead center. Most SSer opt of the spiderless cranksets for that reason.

As for the tension the chain should bounce up and down about 1 inch total. This way it give you some room for error. I just remembered I had the same exact problem you had because I made the tension too high I stretched the PC1 really fast.

Get a new chain and put it on with some slack. Hope this would get rid of all your problems.

[foofighter]

i'll do that, it's been off and on 3 different SS i'm sure it'll help LOL

you make a good point actually with regards to bolting up the gear perfectly centered.

[foofighter]

UPDATE: Thanks to Neil and Jesse at Adrenaline for their input. I left the shop with a SRAM chain to try out and found the root of the problem was indeed the chain and not anything else. all is silent now on my steed.

Thank you Adrenaline!