Thread: Sprockets
View Single Post
Old 11-01-2008, 03:00 PM
Andyinchville1's Avatar
Andyinchville1 Andyinchville1 is offline
Join Date: Dec 2007
Location: Scottsville, VA
Posts: 502
Default Re: Sprockets

Hmmmmm...Interesting situation...."80" CC engine, 140 LB rider weight and an altitude of only 1280 FT above sea level should leave plenty of power to go faster than 21 MPH with a 36T rear sprocket....

I weigh 157 lbs , run a Dax 70 and am only RPM limited when I hit 34 MPH using the 36T rear sprocket....Something is definitely wrong...

Have you tried to "read" your spark plug to make sure the mix is correct?
(I am suspecting you may be running rich....)

Assuming nothing was done other than just changing out the sprocket, maybe the Air / Fuel ratio is off and when you were running the 44T but there was enough OOMPH to swing it to a high RPM (engine relatively lightly loaded) but when you "loaded" the engine up by trying to pull a steeper gear, the fact that you weren't making "normal" power would become more pronounced.....

My other business is lawn maintenance and I have had weed eaters to rev to the moon when lightly loaded BUT when heavily loaded that same weed eater would bog WAY down....

A properly operating weedeater would rev about the same lightly loaded or more heavily loaded (of course you have to give more throttle).

The above analogy is similar to your operating the engine in a relatively unloaded condition when using the 44T sprocket VS changing sprockets to a 36T and thus demanding more "power" from the engine at any given engine speed (like cutting thicker / taller grass).

More often than not in the case of our weed eaters, the exhaust port is plugged with carbon deposits (you'd be surprised how little it takes to adversely affect power ).

So I guess in summary, I would look into the possibility of running a little to rich and then check the exhaust port / muffler for excessive carbon build up...

Barring this perhaps your kill switch or some wire was accidentally bumped so that it is partially grounding out some ignition power? BUT if I were a betting man I'd check the other 2 issues first.

Hope this helps you.

Good luck and let us know what you find as it may help others in the future...


PS - Any chance you filled up with "bad" fuel in the meantime?

Last edited by Andyinchville1; 11-01-2008 at 03:02 PM.
Reply With Quote