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Allright... I 've finally have everything together to put on the 136"x2" track on my '96 Ultra SKS. the 3" rail extensions where kinda hard to find at a reasonable price but I finally got some.

I'm changing the 9 tooth drivers to 8 tooth extrovert drivers and I'm wondering how that is going to change the gear ratio... I'm thinking the top end is going to suffer.

In the Chain Case I''ve got a 20 tooth sprocket on the jack shaft and a 35 tooth going to the drive shaft. What size would I change to in order to maintain the original ratio?

Is it really going to be worth it as I rarely get over 85 Mph, and do mostly off-trail mountain rideing.

Thanks
 

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i have a calculater on my computer for this if you give me your email i will sent it to you or anyboady that wants it, and maybe p man or erick can post it or put it on the site some how, just email me at [email protected] and i will send it to you
 

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I was finally able to get some GREAT lake riding in this weekend, lots of top end action. Mine used to be able to hit 105 MPH at 8100 RPMs. Then I rebuilt it, dropped jets & dropped my drivers from 9 to 8 lugs to accomodate the paddle, and this last weekend I was topped out at 85 MPH at 7800 RPMs. I don't know where the lost Revs went, I suspect it may be due to dropping my mains from 380s to 340s. Anyway, it's roughly 20 MPH slower by gearing down via the drivers.
The way I see it, 85 is still plenty fast enough to hurt myself, and the deep powder is more appealing than triple digits.
 

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why did you drop the jets that much, you are probably running the motor very lean and making less power, also that track will slow you down and if you didn't regear that will slow you down
 

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Nope, I dropped jets because it was set up orginally to run the Iron Dog - full out for hours at very low temperatures.
340s are still 10 over what the chart calls for, but it's still breaking in so I'd rather run a little fat than lean. The plugs are a nice reddish-brown, so I'll probably leave her there.
 
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