It looks a little to the left, but that could be a worn cam-chain.

Yep. Leaving the old guide and cam chain in place is false economy. Use the guide from Hoos Racing, it's made right. MMM at 650 Central picked up some Tsubaki "peanut plate" cam chains cheap awhile ago and passed on the savings to buyers; he may have some left.
 
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Correct me if I'm wrong, but wouldn't a badly worn and stretched cam chain make the notch appear off to the right, not the left? I say this because the tensioner is applied to the backside of the chain and taking the slack out there would roll the cam backwards a little.

Can you tell if someone else has been inside this motor already? If they have, maybe they set the cam like it is because the chain was badly stretched. Putting it where it should be may have had the notch farther off than it is now, so they moved the cam a tooth over. Obviously not perfectly aligned, but closer than one tooth over.

Carefully examine the front guide. They need to be aligned (perfectly vertical) when mounted and many I've run across weren't. This makes the chain run across the guide at an angle and wear off the edges .....

HcIylaP.jpg


6Y8bpxh.jpg
 
Correct me if I'm wrong, but wouldn't a badly worn and stretched cam chain make the notch appear off to the right, not the left? I say this because the tensioner is applied to the backside of the chain and taking the slack out there would roll the cam backwards a little.

Uhm, I wasn't sure of the orientation of the engine in post #56, thought we might be looking from the advance / r/h end which would mean the cam is rolled back a little. But I'm probably wrong.
 
..... and you measure the ring end gaps. Usually, due to a combination of cylinder and ring wear, you find the gaps too big .....

rv0m800.jpg


If the bores are still in spec, you could just replace the rings if their end gaps are too large. If you want nice, tight end gaps, get 1st oversize rings and file the end gaps to the minimum spec (.008").
 
..... and you measure the ring end gaps. Usually, due to a combination of cylinder and ring wear, you find the gaps too big .....

rv0m800.jpg


If the bores are still in spec, you could just replace the rings if their end gaps are too large. If you want nice, tight end gaps, get 1st oversize rings and file the end gaps to the minimum spec (.008").
This I understand.
 
Yes, the ring is still in spec so you could re-use it. So far, I've only rebuilt one that still had in spec rings, and we re-used them. That bike has been running fine for a good ten years now. Normally, I find end gaps up in the 20's, lol.
 
So got my motor all buttoned up and ready to put back in the frame. Sorry it has been a while since last post life and shit. Ya know? Well I got the bb magnet system mounted in my cam. I'm just wondering how I hook up this coil I've read a few things and am just wondering where wore that are coming from the stator plate. There are 5 wires on the box and 2 coming from the magnet pick up that replaced my braker points. So red goes to positive on coil spliced in with hot red/white from o.g harness. Black goes to negative and white is my ground. The other 2 are black/yellow and something else(I'm at the house now bike is at the barn or I'd look) the instructions say these go to the stator plate. Is this from my pig tail coming off my motor or do these connect to my magnet pick up. I suck at wiring just FYI.
 
Remember, lining up the white spot on the Boyer magnet with the hole in the timing plate only gets timing close enough to start. Be sure to follow up with a strobe. For some reason guys tend to line up hole and paint mark at TDC. Big mistake, Boyer marks should be lined up with engine timing marks at full advance.
 
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so i just got my motor back in to my bike. i put the new ignition in its a b.b. blue box. there are 5 wires that come from that box. white; ground, red; to my red/white tracer and also to my positive on my terminal, black; to my negative on my terinal, black white tracer; to magnet pick up, yellow black tracer; to magnet pick up. so i hooked it up correct from what i can see. im getting 12 v + on my battery when it is checked. im getting power to both the sides of the coil on the neg and the pos. I am not getting spark. is there something i am missing. am i suppoused to have power coming from blue box to magnet pick up plate???? any help will help
 
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