My 640 lump - under Master Surgeon Minter

[Minter]

Nikasil relining, about £125 last time I had it done.

Did that include reboring to 100mm as well Pete or just the relining?

Pete's was already a 640 but they have to bore the old Nikasil/Nicasil out before a recoat anyway, so I can't imagine boring to size would add too much if anything (assuming the barrel is suitable and has enough meat on it also)

Could be the way to go for 560 motors then seeing as standard 604 stuff is expensive!

[ZIP TIE]

Yeah even easier/cheaper if it's got an iron liner as you would just need a rebore and no Nikasil.

I've said it before but I really think the 350 owners should look at finding a suitable piston to over bore their lumps with and maybe a stroked crank, as it's a shame to waste a perfectly good engine for a piston and rebore that costs a great deal less than a 604 lump of unknown condition.

[ZIP TIE]

Ron Woods did a very nice kit that would make a short stroke 450cc out of a 350(below) and if I recall correctly you wouldn't need a lot of the parts shown as I think that crank is the same stroke.

[Minter]

Thats interesting Steve, a 450 would be a nice size motor to have.. RW is american tho isnt he?, I'll google him and try and find out more.. If its just a case of a rebore and piston it could be a viable mod..

[ellrider]

Ron Woods did a very nice kit that would make a short stroke 450cc out of a 350(below) and if I recall correctly you wouldn't need a lot of the parts shown as I think that crank is the same stroke.

From my arithmetic it is probably an MT500 top end on the 350 bottom end.

Anyone know if the 500 barrel fits in the 350 crankcase?Will the 500 piston height work with the stroke?

[ellrider]

Yeah even easier/cheaper if it's got an iron liner as you would just need a rebore and no Nikasil.

I've said it before but I really think the 350 owners should look at finding a suitable piston to over bore their lumps with and maybe a stroked crank, as it's a shame to waste a perfectly good engine for a piston and rebore that costs a great deal less than a 604 lump of unknown condition.

Fitting an Iron liner is what I was thinking but you'd need more meat on the barrel to start with. Do any of the CCM barrels have iron liners?

[ZIP TIE]

Ron Woods did a very nice kit that would make a short stroke 450cc out of a 350(below) and if I recall correctly you wouldn't need a lot of the parts shown as I think that crank is the same stroke.

From my arithmetic it is probably an MT500 top end on the 350 bottom end.

Anyone know if the 500 barrel fits in the 350 crankcase?Will the 500 piston height work with the stroke?

The Rotax engines all use the same height barrel, to accomodate the different strokes the height of the piston above the wrist/gudgeon pin is altered so if you put a 500 top end on a 350 you would have a very low compression motor as the 500 piston is shorter.

[ellrider]

From my arithmetic it is probably an MT500 top end on the 350 bottom end.

Anyone know if the 500 barrel fits in the 350 crankcase?Will the 500 piston height work with the stroke?

The Rotax engines all use the same height barre,l to accomodate the different strokes the height of the piston above the wrist/gudgeon pin is altered so if you put a 500 top end on a 350 you would have a very low compression motor as the 500 piston is shorter.

Just as I was expecting.

[ZIP TIE]

But a 500 top end on 350 with a taller piston from Wiseco,Omega etc would work and it would be a cheaper better quality forged piston with more compression (if they have a suitable one on the books of course )

[ellrider]

But a 500 top end on 350 with a taller piston from Wiseco,Omega etc would work and it would be a cheaper better quality forged piston with more compression (if they have a suitable one on the books of course )

A nice little job for you to find out?