New to this site. Bike will not start I think the timing jumped ..pleas help.

[zeben75]

So I got this xs 650 ovER the weekend And I got it running and then I toon it around the block.. whT I should have done is take it easy but I did not lol ( now I am paying for it lol) I felt sometime in the motor when I was down shifting and then it died on me and will not kick back on. I am getting gas and spark in all the right places and I looked at the timing and can't tell if it off can I get so help I want to get this bad boy back on the road
Bty it's a 1975 xs650 hard tail sportster tank straight pipes and no front brake. This bike was a dream to get and now I can't even ride it. Thanks

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[gggGary]

Check compression both sides. Jumped timing is rare, do the troubleshooting and find out what is wrong.

 

[zeben75]

Check compression both sides. Jumped timing is rare, do the troubleshooting and find out what is wrong.

I just took the right side advance cover off an the pin that's in the cam shaft was gone and the part that holds it on was bent like if it ripped out. Do you think that found make it not run ?

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[gggGary]

I'd say that did it! Sounds like you need to remove those parts and see whats up. I have not heard of the pin getting so violently removed. after the pin its just the advance mechanism, shaft and points cam.
Behind the advance weights there is a gland nut that holds the advance plate to the cam shaft I would look at that being loose.
I guess those parts should all come out and inspect them to see if you can figure out why the pin was ripped out. The parts are all available at MikesXS at reasonable prices.

 

[zeben75]

I'd say that did it! Sounds like you need to remove those parts and see whats up. I have not heard of the pin getting so violently removed. after the pin its just the advance mechanism, shaft and points cam.
Behind the advance weights there is a gland nut that holds the advance plate to the cam shaft I would look at that being loose.
I guess those parts should all come out and inspect them to see if you can figure out why the pin was ripped out. The parts are all available at MikesXS at reasonable prices.

Yea I hope that's it. My dad has a 72 xs and be got a 78 bike for parts so I took that motor apart to see if I an take anything off of that.

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[gggGary]

The 78 should have everything you need! That's cool for you! When you have it out I think it is a good idea to polish the advance shaft where it rides on the bushings.

 

[grizld1]

Pin out, timing unit rotor torn up--that's typically what happens when the ring nut that secures the ATU to the camshaft loosens up. The pin is only there for alignment, and when the nut loosens the pin tears up the timing unit. Check compression on both cylinders and make sure you haven't holed a piston before you spend any money on parts.

 

[jay760]

I always use loktite when putting this part back together.

 

[zeben75]

Thanks guys for all the help I will get on that this weekend By the way is there any way I can post a picture from my phone on here ? Or only from a computer ?

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