Just picked this thing up last night.

Its a 2002 Baja, in decent/good shape.

The previous owner is a mechanic, and obviously knew his stuff well.

Last season the top end was rebuilt with a 720cc bore/piston, web cams, mild head porting, 1mm over-sized valves, and has a big carb and full exhaust to match.

He said it has been dyno tuned and produced 58HP. He also said that in his experiences, this particular dyno is not very optimistic, and other dynos such as the Trinity dyno (a bit optimistic) it might have produced 62 or 63 HP.

This thing feels strong. Real strong. (I've had a Banshee, Zilla, one 660 raptor, one 680cc raptor with a Hot cam, a 250R, etc)

I am just wondering how this big guy will do up the hills in the sand against your run of the mill 450s and Raptors/Banshees.

I am 180 lbs. The previous owner is a larger guy, 305 lbs, and said with the mods, he would hang side by side with the 450's and Raptors up the dunes.

Thanks for any input. This seems like a well built, SOLID bike.

 

hmm.. my own research tells me some negatives about the 720 kit.

Any info? It has a JE piston and sleeve.

 

i would ditch the 720 jug because of the sleeve and get you a 730 jug from OMW. much more reliable. i've heard plenty of bad story's about the 720. everything else should be pretty good. and it wouldn't hurt to lighten the pig up as well.

 

Thanks Cobra, but i'm not really interested in hearing bad 'stories', but more interested in technical details of what goes wrong and why its so unreliable.

What physically fails with the 720 sleeve and piston.

I also cannot afford the 1500 dollar cylinder kit after purchasing the bike itself.

If anyone has any technical info or PERSONAL experience with a 720CC big bore DS motor failing, I'd greatly appreciate that info or insight on what happened.

Thanks very much.

ps. I'm a longtime atvconnection user (check join date..) and i'm glad to be back.

 

no problem mr350x, but just in case u need a back up jug. i have a pami 730 jug that is sleeved for a 106mm piston wich makes it a 734 for $350 if your interested. its in good shape too. welcome back to the site.

 

Where are you located? And thanks for the welcome back!

 

Some have had problems with the head gaskets sealing with the sleeved 720 kits. On the flip side some have had no problems running it.

Just something to be aware of is all, and your numbers sound on par, if not a couple low (depending on carb and exhaust).

Chris

 

amarillo TX