Did it Jump?

[XJ Rob]

I was adjusting the carbs today and everything was going well UNTIL.... I revved the motor a few times. Nothing too high. I heard what sounded like the cam chain rubbing against something else. I immediately shut it down. Wondering if i heard it right I started it up for about 2 seconds. It fired right up no problem. I pulled the cover off the timing plate and rotated the motor to "C". While rotating clockwise (SLOW) I noticed that the chain developed slack between the cams. I rotated it a second time and it did it again. Left it at "C" and pulled the chain tensioner. I thought maybe the end of the tensioner was broke off. Everything looked good. I reinstalled the tensioner. I pulled all the plugs and rotated again to the "T". This is where the cams are.

This Is the Exhaust


This is the Intake


I don't think that I bent any valves because it started and ran for a second or 2 before I shut it back down. I guess I'll find out. Hope I'm lucky.

ps. I adjusted the cam chain last week and IT IS possible that I didn't tighten the bolt tight enough before I locked it down. So the chain could have pushed the tensioner back in just enough to jump. Possible????

[randy]

I can't see the cam dots at all in those photos, maybe it's just my eyesdid you try rotating the crank on more revolution? The cams rotate once for every two revolutions of the crank

[XJ Rob]

Oops

A Big Thanks to Randy.
Sorry for my ignorance. I went back out and looked after reading his post and notice I was 180 off. I just assumed (I really need to stop that) The lines shown were the alignment marks. After a MUCH closer inspection I found the "dots" on top and EVERYTHING lined up perfect. It doesn't explain the slack in the chain between the cams as I was rotating the crank though. I'm hoping that it was just the tensioner slipped a bit to cause the slack. I adjusted the cam chain and tightened the bolt a little tighter. I'll put it back together and see what happens.
Thanks

[trbig]

Like Randy said, you may have to turn the crank one more time to get to the "T" again.

I know it sucks, but what you need to do is remove the tensioner again. Since you have the valve cover off, as you remove the tensioner, grab the chain between the cams and pull the EX cam towards the rear of the motor and take up the slack on the front of the motor. Push the plunger in all the way and lock it there, re-install it, and loosen the adjuster bolt so it slaps the chain,(This will turn your EX cam back where it's supposed to be) lock it there, and remove it once again, advancing the EX cam again. Either with a caliper, measure the plunger, or take a sharpie and mark the pluger shaft where it goes into the body. Loosen the set screw once again to see if there is any more adjustment left in the plunger or if it was extended all the way. If it doesn't pop out more, your chain is stretched too far and needs replacing. Also, with the adjuster in, if you grab the chain between the cams and lift, you should not be able to get any slack.. it should be tight. Revving the motor sometimes makes the plunger get pushed in (Out) and will get slack in the chain. If you install an automatic adjuster (Ratcheting) this can't happen again.




Tod

[XJ Rob]

I went back out after I realized my mistake being 180 off. Checked the valve clearance and put the valve cover back on. Adjusted the cam chain again just for S&Gs and it fired right up. It runs as good as it can with slightly worn throttle shaft seals. It's not too bad but they will get replaced as fast as I can get them here. Good thing they are predicting rain this weekend and lower temps next week. Gives me time to get it done.

[tinman905]

Are you referring to the butterfly shaft seals ?

[QUOTE=XJ Rob;2639 It runs as good as it can with slightly worn throttle shaft seals. It's not too bad but they will get replaced as fast as I can get them here.[/QUOTE]

[XJ Rob]

Are you referring to the butterfly shaft seals ?

Yes. I used a little bit of carb cleaner with a hose and sprayed the shafts between 3 and 4 and the idle came up and it ran a little smoother. Although I hit between 1 and 2 and the idle went down like it was getting too much fuel. I know.. I should have installed new ones when I did the carbs originally but I didn't really think they would be bad after only 20K. Again... I need to STOP assuming. Anyone know of an inexpensive place to order them from?

[bikerphil]

These should be the correct ones for the BS-34's, P/N 48-5021....

http://www.mikesxs.net/products-75.html#products