You're thoughts on 3.37:1 primary gearing for 120" e-glide

[outback2970]

I have the parts to do this. Any advantage on a heavy 2 up bagger. Would it be "easier on the engine? Maybe just the 24 tooth comp sprocket and a baker fat shoe?

[N-gin]

Here is my thought. If you have a lot of torque ergo big cu.in. you should make your engine work with the torque it has.
If you have an engine with a short stroke and not a lot of torque right off the rip, then you problwy want a gear ratio to help move you.
3.37 with a 120 is going to be like riding a biking bronco instead of a steed. 3.05-3.15 is good.

[Smarty]

I have the parts to do this. Any advantage on a heavy 2 up bagger. Would it be "easier on the engine? Maybe just the 24 tooth comp sprocket and a baker fat shoe?

As I have said, I did this to 04 Ultra years ago for that reason. It raised the rpms by 300 and put my torque right where I wanted it. In 5th gear just twist the throttle to pass or going up steep hills. Worked like a charm. When everyone else was going to 6 speeds and overdrives loading up their engines, I was putting mine where it is happy to ride.

[outback2970]

Is your 04 Ultra a big inch or stock motor? There's little doubt it would be beneficial in an 88ci. I love it in my Wideglide with a 95". Just wondering about the combo with a 120".

[Smarty]

Is your 04 Ultra a big inch or stock motor? There's little doubt it would be beneficial in an 88ci. I love it in my Wideglide with a 95". Just wondering about the combo with a 120".

98" Dave Mackie semi heads and piston, 10:5-1, roller rockers, Woods 6HG, fueling lifters, fueling oil pump, bigger throttle body, SE spring, 24 tooth compensator sprocket, D&D Fatcats performance baffles, SE adj pushrods, puts out 104-106 hp and 117 or so torque. According to which download, mileage or power. Does ok for a home build mouse motor.

[JohnCA58]

I am running the 3.37 in my primary with the 6spd Baker OD trans,and final drive 23 tooth and 55 tooth rear chain,  5th gear ratio is 3.68 and OD is 3.17     this is with a 151 h.p. 120 c.i. motor.   love this set-up

[1FSTRK]

It would depend on what the torque curve of your 120" looks like.

[outback2970]

Wow. If it looked like that one I wouldn't even need to ask. Must pull like a tractor. Stock Ultima crate 120" for me. (Why do I love sayin 120 so much)

[Admiral Akbar]

Here is my thought. If you have a lot of torque ergo big cu.in. you should make your engine work with the torque it has.
If you have an engine with a short stroke and not a lot of torque right off the rip, then you problwy want a gear ratio to help move you.
3.37 with a 120 is going to be like riding a biking bronco instead of a steed. 3.05-3.15 is good.

Stroke has nothing to do with making TQ..  Displacement makes TQ..  and the TTS100 

[outback2970]

Also, stroke can be a relative term if it's used out of context. The stroke on this 120" is the same as my stock 80", 4.25". So at the end of the day once again Max is correct dammit, it's displacement that makes torque. We can only mess around with components to get the most from the cubes we have and put the peak numbers where we want them. At least that's the way I've always understood it to be.

[Admiral Akbar]

As far as your gearing goes.. I'd probably leave it the way it is and give it a shot.. I'd lean towards the 3.15 gearing as first gear is already pretty low..  I'd say it depends on how much you like to cruise at say 80  mph and above..

[outback2970]

Yeah, it will be the "trip" bike. ie. mostly highway. So 3.15 it is. I would love to see some dyno curves with a stock Ultima 120". How broad is the curve, where does it start making say 100 lb ft of tq etc. Thanks everyone.

[ndmp40]

Also, stroke can be a relative term if it's used out of context. The stroke on this 120" is the same as my stock 80", 4.25". So at the end of the day once again Max is correct dammit, it's displacement that makes torque. We can only mess around with components to get the most from the cubes we have and put the peak numbers where we want them. At least that's the way I've always understood it to be.

Its cylinder pressure that makes power.

[outback2970]

I'll qualify my statement with " all things being equal ". Yes you can run 11.5 : 1 in a 95" and get better #s than a 9.6 : 1 107".  But again, all things being equal.

[jmorton10]

As far as your gearing goes.. I'd probably leave it the way it is and give it a shot..

I agree 100%.

I have 3.37 gearing in my 04 RK with a high compression 95 inch motor, but I love the stock gearing in my 124" RK.

~John

[Buffalo]

  Hell I went the other way when I installed a T124 in my 01 Dyna. I changed from 3.15 to 2.88 to keep revs down and speed up. Long trip show mileage averaging 45-47mpg, at 75-80 mph. It easily pulls this gearing. It will run out to 6200 rpm in top gear (5 speed), that around 150 mph, fast enough for me.
With a FLH, I'd likely leave it at 3.15 as suggested, and only consider shorter gearing if constantly pulling a trailer. The 120 should run effortlessly on 3.15.   fwiw   Buffalo