I have a 88' zilla and my buddy has a 86' lt250r, Both of our jugs are being bored .080 over and the parts guy at the dealer said not to horse on them too much...thats what there for! Anyway it just kind of concerned me hearing it. I've seen alot of machines running on .080 over with no problems and I know zilla can go up to .140 over. Is he full of it? Input appreciated.

 

If you bore your cylinder it will heat up alot faster( use Engine Ice Coolant). also if you scratch your cylinder(ex. sand, dirt or even sucking in a reed) and need to bore it to fix it then you have less room to bore. I heard it can cause some reliability issues, but I think it is mainly from heat.

 

.080 over is it for the LT250, and the Quadzilla can go to .140. Like the other guy said, as you bore, it runs a little hotter, but you should be fine. New York doesn't get as hot as Southern California and i know plenty of guys here are at .080 over.

 

Mine's .080 over and no probs yet!!

 

LOL, no you can still hammer down. Dont worry about it.

 

99.9% of all parts guys are. If they were not then they would be outback working on the bikes making more $s than the counter boy. You can run it just as hard as before.

 

Well guys how does {and this may sound stupid, I don't know}
what about an L.A SLEEVE?? What does that do? give you more or insulation on your original cylinder??Or give you an origanal cylinder spec?
I'm curious to this question too cause the cylinder that I had on to this machine that I've got was bored .080 over and the first thing that I did was replace it with a fresh cylinder and piston,I left the Hot Rod connector alone though.I thought that with an L.A Cylinder you could go to an .080 over size and not worry about it??

 

LA Sleeve is a company that makes just that, sleeves. When you resleeve it will bring you back down to stock bore. I had one installed in my 88' CR250's jug, they are unboreable from factory because of the nikasil coating on the cylinder, but la sleeves are borable, If I'm not mistaken I think they have some sort of brinnel based sleeves material, which makes them hard and long wearing but still boreable.

 

most people sleeve there cylinder when it gets scratched, and they don't want a bigger bore. So they bore it then stick a sleeve in to downsize the bore to any size (not just stock size).