Chain Dropping.....

michael.su said:
I have not tried twisting the derailleur yet but that's next. If that doesn't work I was these:

http://www.bioniconusa.com/cguide/

Does anyone have any experience with them? Is this a good option for me?

Thanks!
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Its just the stubborn in me talking, but it's a solution to a problem you shouldn't have. I'd keep looking into whats causing the issue...but based on my previous threads, I have a hard time moving off a problem sometimes.😀
 
Ok, so for anyone that cares....😀

I re-adjusted the front derailleur so that it was as close to the chain as possible on granny but still shifting well with no rubbing.
During the first ride, the chain did drop but only from the middle to granny, not off the crank like previously. Getting somewhere!

I twisted the derailleur outward just a little as AM had suggested. I'm going to give it a try tonight.

Against my better judgement, I also took a link out of the chain. It looks good with the rear suspension in the relaxed position however, the chain is really close to looking too short when I compress the rear suspension all of the way. 🙄
The way I see it though, I really should NEVER be on the two largest gears at the same time....
If the chain is in that position and I use all of my travel, I may be in trouble 🙁
 
the problem is it's a K2... haha jk

Are the rings too worn? You said you have new chain and cass but nothing about the rings.

Also, is it dropping when the suspension is active?
 
THATmanMANNY said:
the problem is it's a K2... haha jk

Are the rings too worn? You said you have new chain and cass but nothing about the rings.

Also, is it dropping when the suspension is active?
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Old K2's are AWESOME! and you know it!

New chain and cassette, the rings aren't perfect, but not bad IMO.

Yes, it's only dropping when I'm screaming down a downhill section of trail uncontrollably whilst not pedaling. 😀 (only something bumpy/rocky or with drops)

I know...I may have to sacrifice the large ring up front and shorten the chain to get the results that I want 🙁
 
THATmanMANNY said:
it's just chain growth, which is worse on older bikes like a K2 😀
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Despite removing a chain link and twisting the front derailleur outwards, I still have issues with this... I believe Manny hit the nail on the head with the chain growth. I can see how that's a problem when I compress the suspension. Analyzing the mechanics of this tells me that removing the large gear up front and shortening the chain will not help this part of the equation. It may help if chain slack is contributing to the problem but it will have no affect on the growth.
Is there any error in my logic?

While inspecting everything the other day, I also noticed that the bottom pulley on my rear derailleur is pretty worn and shark-toothed. could this contribute to the problem?
Does anyone have one laying around? Do any shops stock them? It's a XT long cage mega 9 derailleur.

The only other explanation for the problem is that I'm getting faster, I guess That's why I didn't notice it as much before. I could just slow down....Na! 😀
 
This may be stretch...but once I got my bike back from and LBS after among other things having all my suspension pivots lubed up. When I got it back my chain was falling off alot and was bouncing like crazy off the front derailur in certain gears. I realized the LBS removed some air in my rear shock (the bike tech was half the size of me...so he must of adjusted it to his weight) and my sag was way too high changing the geometry of the bike as well as the tension of the chain. Once I put the correct air pressure in the rear shock all was good with the chain.
 
My Bionicon c. guide came in the mail yesterday. I'm hoping to try it out tonight. It looks good. Expensive for what it is but the reviews were indisputable.

bye bye chain slap...

IMG_2666.jpg
 
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I'm somewhat bummed the underlying condition was never revealed. But it looks like you're all hooked up and I'm interested how different the chain slap is.
 
extremedave said:
I'm somewhat bummed the underlying condition was never revealed. But it looks like you're all hooked up and I'm interested how different the chain slap is.
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lol, I don't want you to feel that you got ripped off and leave you with no closure on my thread Dave. 😀
The underlying condition is chain growth. As my suspension compresses, my chain grows. (maybe more so with single pivot design?) Not an issue on hard tails of course.
After extensive research on the webs, there is a lot of chatter about it with freeride/all mountain/downhill bikes.
Most of them seem to be using some kind of chain guide for slap and chain dropping.
I also changed a worn bottom rear derailleur pulley and my chain rings which helped tighten everything up but didn't totally solve the problem.

There are other options...pretty much all related to shortening the chain by removing chain-rings, getting a short cage derailleur etc. but it is what it is...
I may still remove the large ring and put on a bash guard but I'll see how it goes.

As for the slap difference, see here:
http://www.youtube.com/watch?v=7W5xA7pd4Gs

I hope this fills that void for ya man 😛

hahaha
 
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michael.su said:
lol, I hope this fills that void for ya man 😛
hahaha
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Nothing fills the dark void.😀

I still say something is wrong elsewhere, unless it's just an idiosyncrasy of that particular suspension design. Before my chain was shortened I did get some gear skip on rough downhills and occaisional drop off the front. Very little issue now. But it's a completely different design so ymmv.
Glad you got it all straightened out!
 
Well, I rode most of Chimney Rock last night and the c.guide worked great!
There was absolutely zero slap and my chain didn't drop a ring even once. 🙂

One thing to note though: my shifting was not as crisp as I like, so I think I need to make some adjustments. I believe this to be unrelated to the chain guide. but who knows, maybe it's a little stiff because it's new.
I had previously made adjustments in an attempt to keep the chain from dropping before I installed it. I think I need to tune her up starting from square one.
The saga lives on....😀
 
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