250 head

[baseballplaya23]

if i have my cylinder bored out to a 265 do i need to do anything to my head?

[xlr810]

No need to modify your head in any way. Just make sure you use a 68mm inner diameter head gasket. Cometic and other aftermarket companies sell them at 68mm, though some of them are somewhat thick (low compression)

[hollywood250r]

You might want to change you squish! Changing the squish band can effect you power!

[baseballplaya23]

wtf is squish and how do you check or change it?

[wilkin250r]

Originally posted by baseballplaya23
wtf is squish and how do you check or change it?

Ok, I HAVE to jump in here, because this is a huge pet-peeve of mine.

Do you know WHY professional engine builders cost so much? Because there are a lot of little details to that require attention for good, reliable power. These aren't little tips or tricks, they're not optional, they are necessities.

Engine building isn't just turning nuts and bolts. It's not as simple as just knowing how to put components together in the correct order. There are many clearances, measurements, and tolerances that play a large factor in power output and/or reliability.

No offense, but if you don't know what about squish, then you should NOT be doing your own engine work. The way I see it, you have three options:

1. Lots of research to learn how to do it yourself.

2. Pay out your nose for a professional to do it.

3. Leave it alone and live with the stock performance.

[250r4life]

well, i have to hop in here now and comment.... the problem is there are a lot of incompetent builders... there are a lot of freaking idiots working, and there arent too many people that i trust with my bike... if i found a builder that i completely trusted i would have him do all my stuff and just pay him. but i found out long ago that most of the people are jokes, and so i began working on my own bikes to learn... im sure thats why other people are working on theres... mine is more a quality decision then a economic decision. however, its true what you say, if you have no idea what your doing you shuoldnt be messing around, especially in your engine... either research the crap out of it, or even these not so great builders would likely do a better job then you... but it is ridiculous cuz even stuff like boring that i cant do in house i cant rely on the local shops cuz they do crap for work, so i gotta send it out to LA SLeeve... its a shame that good builders are so hard to come by

[baseballplaya23]

im not doing my own work im just putting it back together. i sent it out to esr to have it bored and to get the right size piston for it. all i am doing is putting it back together. so can someone answer me? what is squish and how do you measure it?

[JTRtrx250r]

unless you've had alot of mod done to the topened, just put it back together, theres to many variables... if youve just bored it a bore I wouldn't sweat it, it isnt gonna make that big of deal

if you were re-vamping the whole topend... that'd be a diffrent story, but if you just bored it 1 bore... no need to get all tech about it..

[baseballplaya23]

im not exactly sure what bore it was on but i took it to a 262 oh ya thanks jer

[JTRtrx250r]

If in at all doubt, ask ESR ... good helpful guys there;) :cool: