[Yak] TIKIT - de-railing from chainring

[Peter Saint James]

On 18  September2008, at 7:12 PM, PHolden960 at aol.com wrote:

> Happened half a dozen times last Sunday, at least once every time  
> I've  taken
> it out.  Most often happens from 8th gear, but seems to happen in   
> plenty of
> other gears too.  Bike has less than 50 mi on it, chainring   
> doesn't appear to
> be bent.


	You don't say, so I'm assuming that you have the stock setup of a  
derailer in the rear and a single chainring.

	Here are some things to check:

	--Chainline.   Does it look right, especially in 8th gear, where  
you're having the problems?  Or is it contorted enough to create a  
problem.  Is the chainring in line with the chain?

	--Chain tension.  Do you have enough tension when on that small  
gear?  Are the jockey rollers up and down, or are they horizontal  
when in high gear?

	--Chainring.  Check each tooth on the chainring to see if one is  
bent even slightly.  Bending a tooth is easy to do with a folder.   
(Note what position you feet are in when the chain derails.  If it  
happens always at the same place in cycle, this is especially  
suspect.  It would indicate it's happening with the same tooth.)

	--Crank.  Is anything loose at the crank?  If you grab a pedal and  
try to move the crankarm, does it move?  Can you move the spindle?

	--Wheel position.  With a derailer this shouldn't be a problem, but  
the universe is a strange place.  I have an internal gear hub, I have  
problems getting the wheel far enough aft for good chain tension with  
Tikit's style of dropout.  Is your wheel where it belongs in the  
dropouts?  Is it straight?  Is it tight?
	
	Is there any pattern to the derailing?  Does it happen when pushing  
hard on the pedals?  When pushing easy?  When going uphill or down?   
On rough ground or smooth?  When hitting a bump?  Anything?	

								Peter