I'm doing a compression test on our "new" 88 blaster, what is the spec for this, and at what value should the motor be considered for a rebuild??

 

A Blaster that old, if it is still on the stock bore and piston, will probably have enough wear that it will yield a low compression reading. If your reading is lower than 115 psi, then it time for a rebuild. A fresh top end will yield around 135 psi.

 

This is how I did my test, I held the trottle wide open and kicked it over until the needle stopped moving on my guage, the highest it went was 90 psi, it took a lot of kicks to get there, I guess this motor needs to be rebuilt in the future. Will riding with this low a compression hurt anything else but not having as much power as it should?? Do I only need to install a new piston and rings to get my motor back to higher compression, or should it be bored?? Please give me more info, anyone!!

 

90 psi is really low I would be suprised if it would even kick start. You will need to have it bored out to the next size and a new piston and rings. If you are lucky and the clearances check you might get away with having the cylinder just honed. With that low of compression I imagine the cylinder must be scuffed up quite a bit. I would not ride it you can do more damage than good. You are looking at about $160 if you do it yourself except the boring.

Sounds like you did the compression check correctly. Gas wide open and kick till it stops going up. Usually a good 6-10 kicks. A fresh top-end in a stock blaster should read 127 psi. You will never get above that with stock head specs. 135 psi has to have head mods done.