engine compression

[malleryii]

I ride'm but can't fix'em . Just pulled a deal on a 02 viper. Yes I know this is a 4stroke forum but my 04 RX-1LE is too heavy for pounding ditches and powerlines. Thoroughly checked over the sled and everything is excellent. 986 miles . three riding buddies had me check compression with help of course. from front 120#,120#, 100#. the Clutch side is at the #100. Two buddies who are not mechanics say worry. Other bud who tears his apart yearly said not to worry. he check for dust and shavings thorughly and said I should have no problem... Comments greatly appreciated

 

[LazyBastard]

Normal. Clutch side has lower compression ratio than the other two. 5.9:1 as opposed to the other two being 6.7:1. Also note that Yamaha 2-strokes have a much lower compression ratio than other brands. Leads to longer life and greater reliability, so your doo buddies will think that a Yamaha engine is burned down even when its in perfect condition.

 

[malleryii]

Thanks lazybastard. I am looking for others to add their expertise here

 

[yamahajunkie]

LazyBastard
TY 4 Stroke God

 

[Sled Dog]

Pull the plug on the one you think is low in comp add a little bit of two stroke oil roll the engine over a few times to get the oil all over the cylinder and rings. Then do another comp test if it is the same as the first or almost the same it might be a little higher you have no problems. If it goes all the way up to 120 like the rest you may have a problem.

 

[Riceburner]

Malleryii,

You need to look no further than LB's answer.

All what he said above is true.

No need to test any further.

You are good to go.