Triumphrat

Mastiff-man

Will the late model 750 rocker box fit the early 63-70 650 engines???
Thanks, Don

jimmy bush

I think they will fit but I wouldn't recomend using them unless you also convert to the later head bolts (which can be a pia to retorque). The four inner head bolts on a 63-70 apply their clamping pressure through the rocker box to hold the head. The later head bolts apply their clamping pressure directly to the top of the head and are inside the rocker box. The later boxes don't have the support column around the head bolt to allow room for the internal head bolts and there is no clamping pressure applied there. If you installed the old head bolts in the new boxes and torqued it down you'd run a big risk of cracking the rocker box. The new boxes are also located with a small roll pin that is not present on the older heads but could be installed pretty easily. I think these changes were necessitated for some kind of clearance problem when they went to the oil in frame design.

Mastiff-man

Thanks Jimmy, You save me some money!!..My Bike isn't orginal, and i liked how the late rocker box looked.. Back to the drawing board..
Cheers, Don