Gearing up a Dyna?

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Jan 27, 2010 | 12:00 PM

truckerdave

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From: USA

Gearing up a Dyna?

Anyone here ever changed thier trans pulley to larger size to lower RPM's? I have 05 Dyna that's got to be apart anyway to replace belt, pulleys, etc due to fairly high mileage. By going from 32 stock to 34 andrews you go from 3.17 final drive to 2.96. Seems a lot easier and cheaper to do this than go to a six speed as long as i have to replace the parts anyway. Higher gearing using pulley-0 extra dollars, higher gearing using new 6 speed gearset-$700 and some work. I have a 6 speed touring bike and you don't really use the extra gear that much except on a 70 MPH interstate. They give measurements on andrews website for axle movement and it looks like i could either get 2 tooth larger belt or slide axle forward or both. +1 tooth tranny=3.2MM forward, +1 tooth belt=7.1MM movement rearward. Oh, the bike is very well running 95" with plenty of power to pull lower gearing and i have the ability to adjust the speedo through the DTT ignition module.

Jan 27, 2010 | 12:08 PM

fixxr

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From: Pa.

This all seems good,but I just went to a taller rear tire and got the same thing.I have a D-digital speedo that is ajustable too.

Jan 27, 2010 | 12:30 PM

8541hog

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From: Ogden, UT

So you want higher gearing?, why? (3.17 final drive to 2.96 is a higher final gear ratio) I would think on an 05 that would suck off the line. I would not want higher gears on my 05, actually looking to go lower with a 30 tooth pulley.
I have done a lot of cruising at 80 and it's no problem with the stock gearing, not sure what you are really hoping to accomplish.

Jan 27, 2010 | 01:17 PM

rounder

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From: Palm Harbor fl.

go with a smaller rear pulley. You have a 70 drop to a 66.

Jan 27, 2010 | 01:19 PM

truckerdave

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We cruise at 80-85 MPH on the interstate in a pack(club member). I have plenty of power(100 HP/105 TQ) to pull lower gearing. As long as i'm replacing the pulley/belt anyway, why not? It really needs it as in 1st and 2nd gear you pretty much hit the 6200 RPM redline instantly. In other words, when it hits 3000 RPM it's gone like a rocket. I've broke the rear tire loose passing cars @ 60 MPH. I was just looking at my axle, you could slide it forward for 2 tooth larger sprocket but i think i would be more comfortable with just one tooth larger and stock belt. Changing tooth size wouldn't be worth it unless you were already(like me) having to buy a pulley. The pulleys and belt on these things really need to be replaced around 50,000 or so. They can last longer but past that point you risk being stranded 500 miles away from home with a broken belt.

Jan 27, 2010 | 02:10 PM

bikerlaw

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From: Richmond, VA

I like having the lower RPM's on the hyway. If your in there anyways, install the larger pulley. I have posted a similar question and gotten replies both ways as well. I will probablly in the end opt for the pulley swap and get the leser RPM on the hyway, and all I have is a stage one. Only in my case I will take rounders method and do the rear pulley since that will simply be easier for me.

Jan 27, 2010 | 02:45 PM

grbrown

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From: Bedford UK

I have gone the other way. My Dyna was geared for a theoretical 140mph in top. I fitted a SE 21T crank sprocket, so it is now down to around 117mph in top. Rolls on like a Harley should now! High gearing is not a good idea IMHO, these things are overgeared as stock already, so why pile even more on it?