big bore kits

[IRONMIKE113]

this may sound stupid what is the diference between406,416,426,and440 kits and this will help me decide so i need ur help any advice or info would be greatly appreciated. kinda new so just make decision it is due for a top end rebuild.

[2004exrider]

the difference will be the bore size, the bigger piston you get the bigger the bore, in most cases the bigger the bore the more power you get and sometimes a loss in reliability. if your just wanting to rebuild it and get some decent power id get a 416. Run like 11:1 so you can still use 93 octane. it will still be really reliable and push out some good power too.

Jimmy

[JOEX]

Originally posted by IRONMIKE113
this may sound stupid what is the diference between406,416,426,and440 kits and this will help me decide so i need ur help any advice or info would be greatly appreciated. kinda new so just make decision it is due for a top end rebuild.
The short answer is the diameter of the piston and cylinder is greater with each number.

The 440 is a bit different though, if you just want it 'bored' to a 440 a new sleeve will need to be pressed in and the appropriate piston installed or 416 bore can be 'stroked' to a 440. Changes to the crank and/or rod will need to be made for that. Someone else wil have to follow up on thet......

stick to the 416 as most bigger ones tend to run hot if you put-put around it still makes killer power.