Sloppy Cam Splines

Hahnda · Post by **Hahnda** » Fri Sep 07, 2012 9:52 pm

I have a customer bike in the shop. He hadn't had much run time on it since buying it because it had issues and had it in for a general once over. While adjusting the valves there was a pronounced click when the valve was open to its farthest point. Both the intake and exhaust but only on the right side. If you had your finger on the rocker arm you could feel the click.

I finished it up and took it out for a ride. It was a bit noisy. So I give the owner a call and tell him that I have it running well but it does have a bit of a problem. Anyway I get the go ahead to tear into it. Since its a Scrambler I am able to pull the top motor mount and and cam cover and have a look inside. As I slowly turned it over I could see the right cam jumping ahead just as the apex of the cam got past the face of the rocker arm.

I don't have it apart yet but about the only thing I can attribute to is wear in the splines? Loose center nut and it hammered back and forth for hundreds or thousands of miles? I suppose it may also be possible that the center nut is just not as tight as it should be?

Thanks

conbs · Post by **conbs** » Mon Sep 10, 2012 8:24 am

Kevin,

Did you get this bike apart? I am very curious about what you found. I have to admit, I am skeptical about the splines wearing that much, but there is obviously something causing the "click".

Hahnda · Post by **Hahnda** » Mon Sep 10, 2012 8:35 am

I did get the bike apart.

What I found is that I had to tighten the center nut much more than I usually did to get the right cam to tighten up. I checked it against other spare cams I had sitting around and they would tighten up with much less tightening. I think the nut being loose may have worn the splines a bit but they didn't look bad.

This CL had the 19mm splines vs. the earlier 20mm splines as shown in one of the Parts Bulletins.

Does anybody know why they went to a shallower spline?

Hahnda · Post by **Hahnda** » Mon Sep 10, 2012 8:03 pm

So I have another CL77 engine on the bench. This one was rebuilt by someone in Texas. No it was not Ed. Not sure who it was I just know it wasn't Ed. The rest of the bike is in boxes. Anyway I popped of the rocker caps on the right side and that one does the same thing!