PDA

View Full Version : Problems with the Timing Chain


PA440exRider
02-23-2004, 10:46 AM
My timing chain keeps gettin streched. This is the 2nd time in 6 months. Does anyone no what the **** is going on:devil: :macho
44oEX
02-23-2004, 11:12 AM
do you losen your tentioner when you put it on. If you do it you should know what I'm taking about.
PA440exRider
02-23-2004, 11:45 AM
Well the wheeler was my cusins and it was in good hands they tried everything but i might do that next time. Luckly timing chains are cheap.
MIKE400EX
02-23-2004, 02:44 PM
Just curious, how do you know that the timing chain is stretched?
02-23-2004, 02:49 PM
Originally posted by MIKE400EX
Just curious, how do you know that the timing chain is stretched?

exactly
pnut420
02-23-2004, 05:36 PM
Originally posted by MIKE400EX
Just curious, how do you know that the timing chain is stretched?

Yeah sounds more like he needs to just tighten the tensioner down, even if the chain were stretched a bit, you should still be able to get it tight with the tensioner.
F-16Guy
02-23-2004, 05:58 PM
You may want to look at your chain guides. If they're excessively worn (possibly by a tensioner problem), they could be allowing your chain to become prematurely slack. You could also have a problem with your tensioner. There is no way to adjust it, it is spring loaded. I don't know if the service manual will have wear specs for the guides, maybe someone can look it up for you. If the spring in the tensioner is damaged, you'll probably just have to replace it.
02-24-2004, 06:59 AM
Well if you plan on replacing it, I have a stock cam chain that is new that I'll let go for $45 shipped. :cool:
MIKE400EX
02-24-2004, 09:34 AM
Great deal Rico! I'll take 10. LOL:D
PA440exRider
02-24-2004, 10:43 AM
Actually i found out it isnt the timing chain i think is just the sound of the valves. So nothin is wrong with it. But thanx for the suggestions.
UglyMotha™
02-24-2004, 11:22 AM
few of you guys really scare me:o
86atc250r
02-24-2004, 11:47 AM
Just curious, how do you know that the timing chain is stretched?

A couple ways....

1st is that the cam's timing will be retarded with the piston at TDC.

Another way would be that the tensioner is taking up a significant amount of slack (which will also show up as the cam timing being retarded)

In other, more serious cases, the chain will slap against the walls of the guide area, make irregular funny noises and grind away at the aluminum.

I've replaced two chains myself & am probably due for a 3rd - they will go quickly if you put a lot of hard hours on the machine. Mine were all on stock valve springs - if you run heavier springs, the chain may wear more quickly.

Running good oil will help improve the chain's life.

When replacement time comes, order a chain for a CRF or TRX 450R - they're much cheaper & use thicker plates so they're stronger than the stock 400EX chain.
MIKE400EX
02-24-2004, 01:00 PM
Gabe,
I posted that question because I figured if PA440EXRider answered it, that would give us some insight into why they are stretching. Hence maybe a logical reason and possible fix could be offered. My fault, I know you're not supposed to answer a question with another question.;)
86atc250r
02-24-2004, 01:22 PM
Sounds like he found out it wasn't his chain anyways :)