Just wondering what are the symptoms of a stretched cam chain?

1) What's the main cause ? Old age, lugging the motor a lot, lots of
high RPM operation (dunes)?

2) How do ya tell it's stretched out of spec without measuring it ?
Does it make a specific noise.

3) Whats the typical life span of cam chain on a Warrior ? Raptor?

4) Does the Cam Chain Tensioner spring need changed after a period
of time - do they become less effective over time ?

Seems if it was stretched out of spec the valve timing would be off, losing power but that's hard to specifically identify.

I dont think I have any problems, just curious cause I've got three 4-stokes and have never changed/checked them.

Thanks, Eric

 

Mine went after just 4 months of "abuse". I didn't abuse it profusely but I definately stretched its legs often. I am not an obese person either, 5'11" @ 198 lbs, so it's not like my ride was hauling 350 lbs of lard up a hill.
If you put alot of hard hours on yur machine I would change it once a year. Other than that the only advice I have is to check your valve lash often, every to every other oil change would be good.

I really can't see the the chain tensioner wearing out. The spring might soften over time but it is very easy and inexpensive to replace. A good way to check to see if your chain is overly stretched is to remove the tensioner bolt/spring but leave the assembly in the block. Once the spring is removed now you can remove the tensioner body. Pull out on the plunger, if it moves 3 "clicks" or less it's time for a new chain.
I went through 2 sets of rocker arms before I realized the chain was junk.

 

Piece of cake checking it. Follow this procedure.
1-remove bolt on end of timing chain tensioner. It's on the lower left side of the head. The bolt will come out and there will be a spring in there as well that actually applies the tension.
2-get out your metric allen wrench set and take the 2 screws out of the tensioner body. I used a 3/8's drive extension too loosen the tensioner from the gasket that mates the tensioner too the head.
3-the tensioner is free and you can carefully slide the tensioner out. Check out the arm that applies the tension on the timing chain. Now you can pull it on out too see how much room you have for stretch. If you do not have a maintenance manual for the wear specs I will set you up.
4-when putting the tensioner back in make sure and collapse the arm that applies tension. This is done by pressing a little "ear" (for lack of a better word) at the base of the tensioner. After you look at it things will be clear. Install the base of the tensioner while using a new gasket or some good automotive gasket maker.
5-now insert the spring and the bolt that holds everything together. The tensioner will only go out as far as needed too take up tension in the chain.

side note - Guys that were having chains fail were installing the complete tensioner assembled...of course this means the tensioner was completely in the out position. After they bolted their tensioner too the head the chain was trash. Hopefully this helps. It's about a 10-15 minute job.

 

Mine is rode reasonably hard EVERY Sunday since Sept of 00 (when not broke down) and I am about halfway out on the tensioner.

 

It only took me about 4 months to kill it, and that was on a stock engine! I am sure the chain will take more of a beating with the stage 2 cam and KW springs.

 

How long did you wait for the initial valve adjustment and how many times did you adjust the valves? Tight valves will apply more pressure on the chain. About half of my time on the Rap is with a more aggressive stage 1 HC.

 

i jsut got the report on what is wrong with my warrior, i thought it was the cam chain stretched, well no the vavle adjustment nut broke off and they say its in the bottom end.....they say 800-1000$ to fix it. i told them i would od it myself...i already owe them 175 just 4 taking the head off and seeing that this is wrong...grrr. ne way how much $ is it to have your valves adjusted?

 

Gary,

Good thinkin - cause the service manual doesnt give any spec or measurement to go by !

Thanks, Eric

 

go to raptortranny.com and learn how to do it yourself. once you do it once, its easy. and you will wonder why you ever even thought of paying someone 75 to 200 dollars to do it.

 

75-200 wow thats alot bebe