Timing clarification

[cmills83]

I rebuilt the top end about 100 miles ago, when installing the cam chain I was going off the idea that TDC is the middle of the T on the stator cover. Is this correct? I am reading some different things. The bike is a 1980 with stock charging/ignition.

Also, I forgot to install the washer in the middle of the cam chain tensioner, looking at this video is it possible my cam chain jumped a tooth? Or is there something I can adjust here? Seems like the timing is really advanced and I'm certain I had everything lined up tdc. The stator is the new oem replacement from mikesxs.

* The battery was dying in the video so you see the ignition cut out at the end.

 

[5twins]

T.D.C. is the slash mark just to the right of the "T", not anywhere on the actual letter. The timing looks about right. It should be firing at the "F" mark, not the "T" mark. The "T" mark indicates T.D.C. and is used for setting the valves. The timing fires about 15° BTDC. That's where the "F" mark is.

If the washer you're talking about that you left off the cam chain tensioner is that copper damper washer, you can just pull the adjuster screw and plunger out of the housing and stick the washer back on. Nothing inside will drop away or fall out of place.

 

[5twins]

I see from one of your other threads that you say the bike runs good except for a charging issue. That replacement stator may be the problem. Looking at it on the MikesXS site, it appears to be the early type with the grounded inner brush mount. That won't work with the way the brushes are wired on the '80-'83 models. You would need to isolate that inner brush from ground by changing it's 3 steel mounting screws to nylon ones.

 

[cmills83]

Thanks 5twins, I replaced the copper washer and got the cam chain tensioner all re-assembled. Just to confirm this is the stator I got from mikes xs:

https://www.mikesxs.net/alternator-stator-for-80-84-xs650-s-oem-3g1-81610-10-00.html

It seems like it's charging but undercharging (13.5v) unless there is an issue with my wiring or another component.

 

[5twins]

Yes, that's the one I looked at. Their picture shows an early '70-'79 type with the grounded inner brush. Maybe just the pic is wrong.

 

[cmills83]

I see, here is what I got installed

 

[5twins]

That looks OK. You have the late style brushes and brush holder that isolates both brushes from the stator. That's not what's shown in their web site pic. They show the early brush holder and an early set of brushes.