harleyKmodel

I’ve had a 66 XLCH for 2 years and it’s always been impossible to start. Recently I’ve tried to get to the bottom of it and have finally found that no matter how precise I set the timing, I check it again and it’s way off. Something is moving and I can’t figure it. I’m sure I need to pull the cam cover but any ideas what I’m looking for would be appreciated. This is the 4th XLCH I’ve had and never had this problem before. Basically saying that the magneto is attached correctly and I really doubt it’s human error. I’ve even tried more than one magneto.

Starting problems are more often than not due to bad carburation...

Too lean an idle or too low an idle is a recipe for endless kicking...

Your ignition is set by gears, so can't just go adrift after setting it right...

Check your carb before investigating ignition further.

Cheers from Patrick

Have you pulled the mag? Is the pin loose in the mag drive gear?

My first HD was a 64 CH.
I learned quickly to always park it on a hill.
Another option is to fit your bike with the LH controlled spark advance similar to distributor advances on knuckles, pans and XLH’s.
Starting in the advanced position makes a big difference.

64 was fixed mag from the factory, 65 fist year adjustable, then adjustable through 69.

I initially thought it was the carb but I can’t ignore the fact that I can set the timing, start it and recheck it and it will be 10 degrees off. I’ve tried more than one mag with the same results. I replaced the gear on one of my mags and put a brand new pin in it so it’s not a loose gear. I think something is worn or loose in the gear case. Hoping someone has experienced this so I know where to look.

The position of the ignition cam itself is not the only determinant factor for ignition timing.
Don't forget that the gap will effect the timing point. It might be something allowing the points themselves to move or a problem with the rubbing block. I'm not saying this is your problem but until you rule out everything that affects the timing you can't be sure what the problem is.

10 degrees off- advanced? Retarded? Either?

Hi Otis. Hope you are well. If you changed the magneto, you have eliminated the idea of a loose magneto drive gear. The next gear that can spin is on the end of your cam.
Different engine but same concept. During the 90’s a guy brought in a Low rider on a trailer. He said it had been running fine and then it became hard to start…and eventually he couldn’t start it. I went through the normal timing procedure but could not get the cdi timing to align after the closing of the front inlet valve. I decided something was rotten in Denmark, and pulled the cam cover off. After re doing the timing a few times and much head scratching, found that the timing gear had spun on the cam.

You might be able to determine your problem with some fact checking…Which direction is the degree shift… Advance or retard? Is the degree shift the same amount each time?

If you miss your timing mark …. “over shoot your flywheel rotation” it is important to reverse the flywheel at least a ¼ of a rotation and then come back to the timing mark. A ¼ rotation will ensure that all the lash in the gear train will be taken out

I’d say that’s the likely cause. Seldom seen, but it does happen. Cams must be inspected