Ready for Top End Rebuild

[OleDoc]

I read fecal hair then

lucky i had taken all my shop rags out of the shop and put them on my porch to wash.it rained the nite before so i just stuffed them in the airbox.only did a little cosmetic damage

 

[Scorpio1963]

Hey guys can we get use oversize valves in our heads?Say for example I got some intakes from a 650 then had the head ported a little larger and the valve seat cut a little larger so there wouldnt be any shrouding would it work?

 

[xschris]

No xs650 valves are lager than the xs400 ones. The xs400 valves already use all of the area there is to fit.

 

[Scorpio1963]

Porting the exaust chamber a little larger and the valve seat cut a little larger so there wouldnt be any shrouding would it work.I`ll show ya`ll when I get done with it.

 

[xschris]

A xs650 valve intake head size is 1.61 where a xs400 is 1.35 approx. The exhaust is 1.15 xs400 and the 650 is 1.38 approx not sure how you could get it in there I guess you could try and fit the xs650 exhaust in the xs400 intake but I think the valves are longer and the stems are wider, not sure on that tho.

 

[drewpy]

someone did put larger valves in with a 450cc conversion.

don't what they did as all I found were the pictures and a brief description. its in the forum somewhere

 

[Scorpio1963]

As long as the valve stem is the same size diamter and length it will work oherwise it would still work but with alot of $worth of machining mods done to the head.If the above is present all you have do is take a dremel or an upright diegrinder and machine about .075 out around the outside area of the combustion chamber where the valve circumference is.Its done on automotive heads all the time.If the valve shank is wider and longer it could be put on a lathe and machined down to the same diamter of 400 valve stem.