Anybody on here do real motor mods?

[tayyo789]

I'm not talking exhaust, intake, programmer. Like cams, pistons, head work, big bores, strokers, etc.

Just looking for how these bikes take it.

[boost addict]

Try this link , post# 71. Mods are in my sig with the same screen name. You might have to sign up to view the dyno sheets.

http://www.club700xx.com/vb/showthread.php?t=4854&page=5

[tayyo789]

I'm just curious because I'm putting a xx cylinder on my xr650r bottom end, and keeping the xr head, but I'm looking into the head design of the xx some more.

[boost addict]

You can expect 56-62rwhp with the 700xx head. Chris is a member on that site that's building a 700xx with a xr650 head. Nobody has done a build with the xr650 yet, so no #'s yet, but he's close to completion.

[tayyo789]

Yeah, I was browsing around on there and found his thread, with Bo White doing the portwork?

So far, from my research, since I'm using the xr bottom end, I have to figure out what to do about the xx cylinder being about a quarter inch shorter than the xr. So I would have to do like a negative stroker, or space the cylinder up. I'm away at school right now but next week I'm going to have each side by side to compare. Its looking like I want to keep the xr head, and do some porting, and maybe +1 or +2 intake valves.