Engine that has ran hot. What I found when replacing timing chain and guide.

Bike wont even run at all unless it is on that 15 degree mark that is shown on the mikesxs install. So I am not sure what to think. Its just depressing. I am not the person that has the money to drop this off at a shop and can work on a car all day long but am stumped when it comes to a 1977 xs 650. Just dont have a clue. I am still hoping with this new timing chain and guide that she wont heat when it warms up around this area. I am going to have to run it at the timing marks that the bike decides to run at and hope for the best. For all I know the engine was built or worked on that didnt do justice to the rings and who knows what else.
One odd thing is when I retarded the timing when I gave it more throttle the timing would go more retarded than advanced not sure why.
 
The marks we've shown you in pics and drawings are for a stock rotor mark. If you've found and marked TDC, the Mike's drawing could be close - but, I'd want to verify it with a degree wheel.........
 
If a battery was in the mix did it help?
Absolutely. If kickstart only try a battery 12V & ~5.5Ah+

There's a thread around here somewhere with an XS charge ignition and same issue: took days n days to figure it out
 
Hmmm. OK, I pictured a stock rotor/stator and you have the PMA rotor.....so a little different.

What I might do is find TDC mark the rotor AND sidecase TDC, then use a degree wheel to determine where "idle F" (15*) & "Advance F" (40*) should be on the sidecase.

I'll find ya a printable degree wheel......
I did not take the time to read this correctly this is what the bike is doing. Fingers crossed!
 

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By using this the engine is idling at 15°s and advancing to 40°s. The only thing that bothers me is the electronic advance installed must be advanced all the way to hit the correct marks.
 

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The bike will probably like it better retarded a few degrees and it won't adversely affect performance. Try 13 @ idle and that should result in 39ish @ 3000rpm
 
And... now that I know you have the E-advance ignition; that was definitely the issue with a capacitor: would act-up, quit after 20min. Duracell SLA battery fixed it
 
Absolutely! Give that thread a read when ya have the chance
 
Absolutely! Give that thread a read when ya have the chance
Read it. But what I think I gathered is that they may have a had a bad capacitor. I do how ever have a small battery that I bought and used to get the bike going when I first started the build to make sure the bike ran before the 300+ hours of fab work. I will use that as soon as possible.

Thank you all for your knowledge!

Would love to find another engine to work on and replace this headache. But far and few around here.
 
Read it. But what I think I gathered is that they may have a had a bad capacitor. I do how ever have a small battery that I bought and used to get the bike going when I first started the build to make sure the bike ran before the 300+ hours of fab work. I will use that as soon as possible.

Thank you all for your knowledge!

Would love to find another engine to work on and replace this headache. But far and few around here.
Hard part is that I dont have any room for the battery as I changed the frame and bike to where it was made just to fit the capacitor.
 
Hard part is that I dont have any room for the battery as I changed the frame and bike to where it was made just to fit the capacitor.

Duct tape one on until you can confirm that is in fact a fix to your problem.

When fix is confirmed, figure out a way to make a mount for it.
 
Check out the size on that Duracell and also on a Antigravity 401 or Shorai LFX07L2 LiFePo; they ain't much bigger than a Cap
 
Quick side question here.... Where did you find the timing kit for your bike? Im currently gathering parts to. Tear down and rebuild mine, but I cant seem to find a decent timing kit. Any help?
 
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