ORIGINAL: RaceCity
One tooth is the same as a million. One tooth equals quite a few degrees of timing error. The motor will run like crap.
Make sure the timing is dead-on. There is only one correct setting.
The "One tooth is the same as a million" is not correct. Try 180 degrees off, for example, and you will see what I mean. The engine won't start, let alone run. With one tooth off, the engine will still run, just not as good as it should.
"Make sure the timing is dead-on" is excellent advice for this discussion.
"There is only one correct setting" is not all together correct, considering what effect cam timing can have on an engine.
But, in this instance, and without a way to
slightly alter cam timing, I would stick with the factory setting.
Also worth noting, this is a
used engine, and as such would have some wear in the cam gears. How much is the question.
A lot of wear could cause the cam timing to be a bit retarded. Enough to cause running problems. That's why people replace timing belts and timing chains in their vehicles.
ORIGINAL: gjeffers
richard, Race is right, if your timing is off just one tooth you wont get close to 9100 rpm with that prop
I don't know how much effect a tooth off makes to a Saito.
BUT, I know, from personal experience, on a Chevy V8 engines, which are a 4 stroke engine, just bigger, that with the timing retarded one tooth, the engine will still run, just not strong. Nor will it rev quite as high as when the timing is set right, or
slightly advanced.
With the one tooth retarded cam timing, on the Chevy V8 engines, not only would the engine not rev as high, but also rev slower, and the engine will run hotter also, which can kill your engine.
I would say tear it down and make sure. It's not
that big a job, and then you won't have to worry about "is it right, or not".
The peace of mind is worth more than the little time it would take to tear it down and make sure. At least to me.
Of course, "tearing it down to check it out" is just my opinion too, of what needs to be done.
Note: If you have no experience with tearing down engines and repairing them, then get some help from a friend that does and learn how at the same time. They are worth learning about.
There is also some good reading about Saito engines here;
[link=http://www.rcuniverse.com/forum/m_5843055/tm.htm]The Complete Saito Notes by Bill Robison[/link]
And here's the Saiyo manual;
[link=http://www.horizonhobby.com/ProdInfo/Files/SAITO_Small-Medium_single_cylinder_Manual.pdf]Saito Small-Medium Single Cylinder 4-Stroke Engine manual[/link]
Good Luck!! I hope you get it figured out.[sm=thumbup.gif]