Does anyone know if anyone has put a Bayou 250 piston in a 220? The 250 piston is 2.0 mm larger than the 220. Max overbore piston available for the 220 is 1.0 mm over. Is the weight the same? Can you bore the 220 cylinder 2.0mm? How 'bout dome/valve interference, etc.??? The stroke is the same on both, so I'm guessing the compression height would be the same? Any comments would be appreciated. Thanks!

 

Don't know the answer to your question...but check with a machine shop that bores and hones cylinders. Those guys are usually fairly savvy and will know what can and cannot be done when it comes to boring out a cylinder.

 

When I posted this, there was a 250 Bayou piston on ebay. It's long since gone and I'll probably bore it this winter and put a 1.0 mm oversize Wiseco in it. Thought if the weight and compression height were the same, the 250 piston might work. Maybe someone will know before I buy the Wiseco piston. Guess I should see if the connecting rods are the same for the 250 and 220 might help me with the compression height issue...

Thanks for the reply

 

I dont think that you can do it. My old cylinder was bored to 1 mm over and the walls of the sleeve were pretty thin. What you could be able to do is get the cylinder from a 250 and have the case machined to use the 250 cylinder. It should work i think thats all that kawasaki did. The only thing is the compession in the 250 is lower its like 8.6 or 8.9 i cant remember exactly the 220 is 9.3. So you end up with the same power output as the 220 because of the lower compression. I dont think anyone offers a higher compression piston either so youd be stuck with the stock compression.. I got another cylinder for my 220 off of ebay and had it bored .5mm over and put in a wiseco piston kit and it runs beautiful. If you cylinder isnt bored already go with the .5mm over then you will still be able to bore it out one more time if you have to.

 

I've already got an extra cylinder off of Ebay. It's scratched and might clean up at .50, but I'd hate to buy a .50mm over piston and then it wouldn't work. The stock one on the 220 now might work, but it smokes a bunch. (The carb to air cleaner boot was off when we bought it.)(Bought it really cheap.) I have no idea what it looks like, but I'm sure it's worn some. Think I'll just buy the 1.00mm oversize and bore the extra cylinder. Thought it would be easy to have all the parts ready, then just do a quick switch. (But then the valves will end up needing work &/or the crank pin bearing or ??? will need replaced too! [img]i/expressions/face-icon-small-blush.gif[/img]) )(So much for a "quick switch"!)

 

yeah your better safe than sorry. i feel your pain about quick fixes lol. everytime i fix something i end up finding something else that needs fixed. but im finally done and it runs so nice and quiet. i dont think the people i got it from ever changed the oil lol they just kept adding. my con rod and all my main bearings are all still good even though its an 88

 

My son bought this with "lawn mowing" money. It's a 91 Bayou 220 that is visually very clean. No cracks in the plastic, minimal scratches, decent tires, etc. He got it for $350. First ride it was leaking and blowing oil all over the place. The timing chain was shot and it had probably 2 qts. more oil in it than it was supposed to have. I put a carb kit and timing chain in it, fixed most of the oil leaks, but it still has a ton of blow by. He should have about $700 in it when we're done. Should be pretty nice for a 13 yr. old kid. Fun to ride this summer, but needs the final touches this winter.