650/X-2 650 bored

[Austin]

I am looking at buying a 650 top end with a 5 millimeter bore. Is it worth it power wise or will i not be feeling all that much more power? Does any one have the cyliders and pistons to do this that they would want to sell?

 

[Winter X2]

Buy a 750. 650 bored is no comparison. Bolt and go. Just a little work on the case to make your 650 electronics. work.

 

[kevbo]

There was 80mm pistons and sleeves made for "mod" class 650s as well as even larger bore aftermarket cylinders. All that ended 20 years ago when the 750 was introduced, they are rare these days. If performance per dollar is important then get a good big-pin bottom end and choose a 750-800 cylinder that meets your needs. I dont understand the fascination with 650 ignitions on 750s, the SXI ignition is better suited.

 

[Austin]

I gave up on the 650sx i was going to buy with a blone motor. That was why I was asking about it. Now i got a 550 for free that i am going to put a 440 drive line in it with a 550 motor with a 60 over bore with new cylenders and pistons. I would like to drop a 750 in it if I can! Is it really hard to covert the 550 to that?