Hi all, have been watching the thread about changing gear ratios, I have a 2001 Heritage Springer and wondered if anyone else lowered the gear ratio, I read all the stuff from gnm109 and things are diff. between his 04 Ultra and an 01, I don't want to lower it alot, just a little to stop lugging at diff. speeds, thanks in advance for any help, Doc.
Doc,
You are needing a higher (numerical) gear ratio to eliminate lugging.
On the Harleys you can go to a smaller motor sprocket, a smaller transmission output sprocket or the rear wheel sprocket.
Several after market vendors have these items cataloged. Drag Specialties, Custom Chrome, Karata, etc.
The motor sprocket change is probably the least expensive as the others will require a new rear drive belt $ and a lot of labor $ to change over.
Lonnie
Northwest Sidecars
Hackin', thanks for the reply, I looked in my owners man. and I have 25 tooth eng. sprocket & 36 tooth clutch, 5th gear ratio of 3.150,...gnm109 sez 24 tooth eng. & 37 clutch...I wonder how much diff. there would be if I kept my stock clutch, (36 teeth) & went 1 tooth lower on the eng. (24 teeth) I think I could still use the same primery chain, it sure would be alot cheaper, everybody let me know what ya think, thanks, Doc.
Back when sidecars were in vogue for the Harley FL's (74 CI) the engine sprocket was 24 teeth for the solo bikes and 22 for the sidecar rigs.
The EL's and flatheads also used a 21 tooth engine sprocket for the sidecar rigs or Servicycles (trikes).
I think I still have a 21 tooth sprocket hanging on the shop wall for a Panhead.
Lonnie
Originally written by David on 9/27/2007 9:52 AM
Hackin', thanks for the reply, I looked in my owners man. and I have 25 tooth eng. sprocket & 36 tooth clutch, 5th gear ratio of 3.150,...gnm109 sez 24 tooth eng. & 37 clutch...I wonder how much diff. there would be if I kept my stock clutch, (36 teeth) & went 1 tooth lower on the eng. (24 teeth) I think I could still use the same primery chain, it sure would be alot cheaper, everybody let me know what ya think, thanks, Doc.
Hi,
The 24/37 combination will fit with a stock chain. If you go to 24 and leave in the 36 tooth clutch basket, you would wind up with 3.28:1. That would be a little better.
Now for the bad news: The chain, although it would probably work, will not adjust properly. Your chain shoe will be close to the upper limit of its travel, making for more wear, more heat and possibly a shorter life.
The nice thing about the 24/37 change is that you get to use the same chain. Discounted, the replacement clutch basket is $251 and change. The 24 tooth compensation sprocket was another $102 IIRC. I bought my parts from Zanotti's HD on the internet. It was a very straightforward modification and I still have the parts removed should I ever wicsh to change back.
Happy Trails.
