What the heck??

[rsor]

How the heck did this happen?

 

[TwoManyXS1Bs]

Yup, the threaded part cracked and separated.
Possibly from abusive hammering, tightening, of the advancer nut.

I have an XS1 cam, in excellent shape, except for a similar cracking in the same threaded area. Have a plan to weld-up the area, and recut the threads...

 

[gggGary]

Guys putting bushings in tci cams have done that lots of times.

 

[GLJ]

I would bet if you didn't want to replace the cam you could clean the cam up enough to install a Boyer.

 

[GLJ]

And then again maybe not. Could be worth looking into.

 

[WideAWAKE]

Guys putting bushings in tci cams have done that lots of times.

could you expand on that? I’m about to install some later today. Just thought they tapped in? Granted they are not oversized...

not tryin to blow up my cam here with some blatant over sight on my part. Haha

 

[gggGary]

could you expand on that? I’m about to install some later today. Just thought they tapped in? Granted they are not oversized...

not tryin to blow up my cam here with some blatant over sight on my part. Haha

I haven't talked to factory engineers....
When Yamaha stopped using the advance rod, 80 on they quit final reaming the cam bore to accept the bushings. Try driving a bushing in a too small hole and something has to give, the thin neck at the back of the threaded area is often the loser. Another possibility is sloppy tolerance, (too big OD) of aftermarket bushings. Result would be the same.

 

[Jan_P]

I would bet if you didn't want to replace the cam you could clean the cam up enough to install a Boyer.

I would give that a fair chance for success.
The broken tip put back with a spot weld or " hard " locking compound
( Or something )

http://yamahaxs650.dk/tips/Boyer/default.aspx

The rotor with the magnets are hold into place with the nut on the right side ..
Giving a compressive force holding it together so to speak.
I don't believe there is big forces so with some tricks it would be doable
Instead of buying the Boyer directly the 8 mm stud one can buy at many places here and some testing can be done
With washers and nut see if it gets stuck solid when tightening the nut.
Or if perhaps an adapter shall be Machined.

 

[WideAWAKE]

I haven't talked to factory engineers....
When Yamaha stopped using the advance rod, 80 on they quit final reaming the cam bore to accept the bushings. Try driving a bushing in a too small hole and something has to give, the thin neck at the back of the threaded area is often the loser. Another possibility is sloppy tolerance, (too big OD) of aftermarket bushings. Result would be the same.

well that kinda seems like a no brainer... it’s not a sledgehammer fit.