Upson Racing Gearing Question 2010 RMK assault

teamlipske

New member
I switched from the 2.4 lug track to the 1.38 cobra track on my 2010 rmk assault. Stock gearing is 20 top and 41 bottom. I have a 22 for the top and just ordered a 39 for the bottom. Does anyone know if this will work for me? I know the 2011 and up switchback assaults run a 23T and 39B. If I do this gear change will I get away with running my normal clutch weights?

No theory's please. Just facts.
 

indy_500

Well-known member
Not sure why you'd want to do that. If your looking at running trails only I would not make a 3 tooth change. It will feel like a dog.
 

xc500mod

Member
Gearing

Not sure why you'd want to do that. If your looking at running trails only I would not make a 3 tooth change. It will feel like a dog.

Team Lipske,

I've noticed from other threads that you've recently replaced this 800 motor with a custom rebuild by Indy Dan. If I understand correctly, you went with the block riser and the long rod kit. This should give you more torque.

From my physics days: Torque is defined as the force that tends to produce rotation or torsion... a measure of the effectiveness of such a force that consists of the product of the force and the perpendicular distance from the centerline of action of the force to the axis of rotation

The longer the stroke, the more offset the crankshaft pin has from the centerline of the crankshaft. This means the connecting rod can exert more leverage to turn the crank as the piston descends on the power stroke

I have been banging my drum on this topic for sometime now. You guys need to determine whether you're going to be needing the low end hound-dog power, or the lake racing light-your-a** on fire top end. Your new and improved torque should help you with either.

When I run Lake O'Brien road out of Upson I like both, that's why I run the stock settings. But I do have a Ross Schmidt crank that can handle the wear and tear of Northern Iron county and my rip grippin' throttle thumb.

I think you can get the best results with a lighter can, louder (but not too loud) pipe, and some torquey type clutch mods.

Best of luck and remember, please remember, keep the hand signals to a safe and effective minimum.

XC500mod

"custom sled, custom boat, custom wife - custom life."
 

Bradzoo

Active member
22:39 Gearing with a 76 link chain is what the factory specs are for running the 1.352 lug Cobra track as an on trail option, Clutch weights should be 10-68 for 0-2000 ft, this will give you a place to start anyway and you can personalize from there. I have the shop manual for this sled if you would like to know anything else.

Bradzoo
 
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teamlipske

New member
Thanks Bradzoo,

Thats what I went with. I will look you up if I have any more questions I am sure I will!

XC500MOD this torque stuff is pretty detailed, but thanks for spelling out my options. Why don't you like hand signals? Who is Ross Schmidt? What kind of Custom Boat do you have?
 

indy_500

Well-known member
Thanks Bradzoo,

Thats what I went with. I will look you up if I have any more questions I am sure I will!

XC500MOD this torque stuff is pretty detailed, but thanks for spelling out my options. Why don't you like hand signals? Who is Ross Schmidt? What kind of Custom Boat do you have?
Ross Schmidt is a crank/engine builder
 
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