720 big bore kit

has anyone heard of a 720 big bore kit seems like i saw one these in dirt bike magazine several years ago any imformation will be appreciated :D

yeah, i seen one thing on a web site.....720 cc.......dont remember where tho sory.

that just seems like too much IMO. Like you would be risking way too much reliability.

There's no way the cylinder is thick enough to go that big. 680cc is already getting pretty thin. Maybe with a stroker crank, but then I think it would be very slow-revving. The 680 already makes TONS of torque- any more would be overkill, IMO.

i think it was a new cylinder that i seen (very expensive like 2000 bux) that was made to 720. i think just a high compression piston, exhause, carb, and what not is good enough.

I believe Baja Designs was designing a big bore kit for the 650R. It was a 710cc or so.

yeah BD had 710 kits--so did a german motard outfit...

having done the 680 mod--i am a big fan of more...i do know of one guy who had issues with the 710 at Vegas to Reno 3 years ago...might want to go easy on the compression.

A place called LA Sleeve did (still do?) a 720 kit for the 650L. It was tested in the January 1998 issue of Dirt Bike. Back then the kit cost $350 (piston kit, gaskets, and sleeve) and machine work was $305 (had to machine the cylinder & cases). HP went from 34.6 to 41.4 (no other mods were done on the test bike).

wow, thats a bit of a jump.......what was the torque increase?

They didn't give any #'s on torque which seems really strange. You'd think the torque would be impressive as well...

I emailed laseeves and got no response back approx 8/15/05.

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