four stroke cylinders

[aloha450x]

i changed the piston on my 450x once. do you not rebore them? what makes them diffrent from 5hundy cylinders. i know another dumb question

[bigjay]

what makes them diffrent from 5hundy cylinders.

the main difference is that they have a bunch of suck all over them and 500 cylinders lack the suck


in all seriousness if the piston is bieng replaced due to age/wear the cyl. should be bored, that goes for all internal combustion engines

[aloha450x]

it just seems that you don't hear to much about reboring a four stroke. was just wondering if there is something you can do to keep from reboring the 5hundy cylinder and just change rings and pistons

[sabreguy]

That's because they blow up before they need a bore job!

[madmcnish]

It all depends on the piston & cylinder wear and the required tolerances.
For example: You may need a new piston, but the cylinder bore shows very little wear and is still within tolerance, so you wouldn't need a re-bore.
The 5hundy has an uncoated steel cylinder liner which is relatively cheap to rebore.
Most other bikes (including 4 strokes) have a coating on the cylinder (Nicasil for example). This coating is harder and longer lasting than plain steel, but the cylinder requires to be re-plated and then re-finished to the required bore when it's worn-out.
This costs a LOT more than just a rebore.

[britincali]

^^^ Nailed it.


Also a lot of these new 4strokes have very little barrel material, you sure cant bore 'em 5 times