Stud size differences '71 vs '72 on up

[XSv650]

Well today I finally got around to removing my road rashed head pipes from my '71 and was going to quickly swap them with the better off yet not perfect pipes from my '72 and everything was going smoothly until I discovered upon reinstalling the pipes on the '71 that the exhaust studs are smaller in diameter, 8mm vs. 10mm on the '72. Which isn't really a problem for fitment on the '71 but IS a problem reinstalling the pipes from the '71 onto the '72 and at first I thought maybe I had had too many Cadbury eggs for breakfast and was just whacked on an over indulgence of sugar, but nope, indeed the studs are different in diameters as are the collars. So, I thought I'd look up the part #'s online and see if they were different, nope, same numbers for the '70, '71, '72 and so on.

Anyone else run into this? I also looked around on Mikes, 650 Central for exhaust studs and surprisingly no one had them available for sale. I kind of figured these were a common part and would be available somewhere, but no bueno.

-XSv

[pops]

I found that out the hard way, too. I bought a NOS left side header off eBay for my '72. Found the holes in the collars are too small for the studs on my '72. I figure if I ever really need to use the header, I can either replace the stud or drill the collar. Let us know if you find smaller studs and what size and pitch they are.

pops

[XSv650]

Pops, I'm going to go the "drill the collar" route. I looked the '71 over to see if I could possibly install the larger 10mm studs and I'm a little sheepish on that because the upper inside studs are very close to the edge of the flange of the head and I don't think I want to tempt fate so I'm going to leave her just as she is. I'll keep you posted if I find the 8mm's somewhere.

-XSv

[XSv650]

Pops, I found some OEM 8mm ones if your interested.