Planet Minis

mxracer49 · 07-25-2008, 06:57 AM

Reposted with correct heading.

02 XR70 with 88kit with what I think is a stretched cam chain. It has gotten extremely noisy the past few times out. I took off the cam chain cover on the head last night and rotated the flywheel while watching the chain. It has a "catch" in it. Hard to explain but it will stay tight until you rotate past TDC then the chain becomes very loose to the point of dragging on the cylinder. I took out the back tensioner and reinstalled several times with no help. Does the piston have to be in a certain position when putting the tensioner back in?

It died last night and wouldn't resart. Finally got it started and thought I needed to adjust the valves again. Did that and it still wouldn't start. That's when I started digging a little deeper.

I'm starting to wonder if the timing is 180 out on this thing.

Thanks all
Darin

bat999 · 07-25-2008, 05:46 PM

Quote:

Originally Posted by mxracer49

Reposted with correct heading.

02 XR70 with 88kit with what I think is a stretched cam chain. It has gotten extremely noisy the past few times out. I took off the cam chain cover on the head last night and rotated the flywheel while watching the chain. It has a "catch" in it. Hard to explain but it will stay tight until you rotate past TDC then the chain becomes very loose to the point of dragging on the cylinder. I took out the back tensioner and reinstalled several times with no help. Does the piston have to be in a certain position when putting the tensioner back in?

It died last night and wouldn't resart. Finally got it started and thought I needed to adjust the valves again. Did that and it still wouldn't start. That's when I started digging a little deeper.

I'm starting to wonder if the timing is 180 out on this thing.

Thanks all
Darin

If it was out 180 it would not run.....

mxracer49 · 07-30-2008, 07:49 AM

Old chain was stretched beyond belief. I ordered a new one and actually thought they sent the wrong size. Until I counted the links.

76CR125ME · 07-30-2008, 08:35 AM

thanks for the follow up post...
Im doing a build on a motor that
has the same symptom...

THANKS

07-25-2008, 06:57 AM	#1 (permalink)
mxracer49 1st Gear Member Join Date: Oct 2007 Location: Kansas Posts: 111	Cam Chain Problem Reposted with correct heading. 02 XR70 with 88kit with what I think is a stretched cam chain. It has gotten extremely noisy the past few times out. I took off the cam chain cover on the head last night and rotated the flywheel while watching the chain. It has a "catch" in it. Hard to explain but it will stay tight until you rotate past TDC then the chain becomes very loose to the point of dragging on the cylinder. I took out the back tensioner and reinstalled several times with no help. Does the piston have to be in a certain position when putting the tensioner back in? It died last night and wouldn't resart. Finally got it started and thought I needed to adjust the valves again. Did that and it still wouldn't start. That's when I started digging a little deeper. I'm starting to wonder if the timing is 180 out on this thing. Thanks all Darin

07-30-2008, 07:49 AM	#3 (permalink)
mxracer49 1st Gear Member Join Date: Oct 2007 Location: Kansas Posts: 111	Re: Cam Chain Problem Old chain was stretched beyond belief. I ordered a new one and actually thought they sent the wrong size. Until I counted the links.

07-30-2008, 08:35 AM	#4 (permalink)
76CR125ME 1st Gear Member Join Date: Apr 2008 Location: Syracuse NY Posts: 116	Re: Cam Chain Problem thanks for the follow up post... Im doing a build on a motor that has the same symptom... THANKS

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)