big bore

[cruza]

howzit those who have used a big bore kit, do you have to line bore the small ends or did your bearing and pin slide right in.im figuring a bore would mean case splitting and crankshaft split.
did you like results of 750,8** ,was it worth it
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[jay760]

there are several options

707cc: all you have to do is have the standard bores bored out to suit the pistons

750cc: if it's a mikesxs kit just a case of swapping pistons and barrels, otherwise the barrels have to be relined

840/880cc: the top of the engine cases have to be bored out to take this, barrels relined unless it's a kit from heiden tuning where they have piston and barrel kits with bigger fins but only for the 533 engine at the moment.

Taking it past 750/760cc is alot of work for not much gain unless you are racing, though it does tend to piss you off when an 840 passes you when you are going flat out.

I didn't think there was much differance in performance between the 707 and the 760 until I tried them within a couple of days of each other, my 760 would leave my 707 standing

 

[Sundie]

Plus, going to a 750 is awesome for doing all the rpm reduction stuff. ie: 18 tooth front sprocket, 30 tooth rear, and the Mike's 5th gear, and still have gobs of pulling power without downshifting.