nick8687
New member
Hey there, I am fairly new to this site, but it has been very helpful to me thus far (far more than any dealer ever could be!!!) I have owned mostly yamaha toys and have had nothing but good luck (06 kodiak 450,91 Phazer and 97 SX 700,98 srx 600) but I recently bought a viper from a member of this site. I t is an 02 with 5100 miles on it, mint shape and obviously been well maintained and taken care of. After a couple of week after getting it home in the garage and inspecting it, I discoverd that it only has 110 lbs. compression in the pto side cylinder, (other two about 130), the sled is mostly stock except for clutch work and a can. Is this compression reading good enough to ride another season or should I re ring it, and if so is there anything else I should check for or do. The sled starts and idles fine and seems to be no apparent problems. Any info or suggestions would be much appreciated as I know there are some very smart yamaha wrenchers out there that know there way around these things. Thanks alot for any help.
>>>NIcK<<<
>>>NIcK<<<
sound machine
That sounds normal...the pto side always less than the other two...10-20% of the other two...best thing to do is take off the exhaust "Y" manifold, take a light and look up inside, you will know if the motor has proper mixture and heat range...If it's been abused it will have lines on the exhaust side, you will see carbon...you will now then if it's a rebuild...now is also a good time to clean and adjust the power valves while the "Y" is off...When everything is o.k. the close it up and then adjust your oil cable a little rich, 1-2 mm less ( 20-23) so go to the lesser and your done that engine should do ya a few years...Good luck and post findings if you see something inside...Mike
That sounds normal...the pto side always less than the other two...10-20% of the other two...best thing to do is take off the exhaust "Y" manifold, take a light and look up inside, you will know if the motor has proper mixture and heat range...If it's been abused it will have lines on the exhaust side, you will see carbon...you will now then if it's a rebuild...now is also a good time to clean and adjust the power valves while the "Y" is off...When everything is o.k. the close it up and then adjust your oil cable a little rich, 1-2 mm less ( 20-23) so go to the lesser and your done that engine should do ya a few years...Good luck and post findings if you see something inside...Mike
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