I'm getting installed a set or Arlen Ness rims, with the matching chromed pulley on my 2007 Deuce. The stock Deuce pulley has 66 teeth while the 'Ness product has 70 teeth.

Will this change cause a noticable difference in performance? What if any change would be required to the transimssion gearing ratio to compensate for this change? Can the original gearing ratio be retained if the primary pulley is also changed?

My basic understanding is that the larger the rear pulley, the lower the power delivered to the tyre and the higher the revs (same principle as a geared bicycle). Would this change of 4 teeth produce a noticable difference in HP and what considerations should be given to the longevity of the transmission and the engine?

Any help or experience anyone has here would be appreciated before i give the stealers permission to go ahead.

 

If you decide to change pulleys, I might be interested in your 66-tooth.

 

iclick,

yeah ok - the pulley (66 tooth) is definately coming off... can't have a not matching pulley after plashing out on matching rotors for the Arlen Ness rims!!

No idea what it's worth... can i get back to you once the installation has been completed and the part is ready for shipping?

 

I'll check what they've been going for on Ebay, and need to make sure your Deuce pulley will fit my SG. I think it will. I have a spare wheel and a second sprocket and rotor would be convenient.

 

Hey FXSTD.AU,

DId you notice any changes in performacne with that 70T rear pulley? I have an 07 Heritage Softail Classic and I want to replace that stock 66T pulley, but I can't find any 66T, I can find a bunch of 65T and 70T.

Does anyone else know if a 65T or 70T pulley will cause a noticable change in the gears?

Thanks,
Paul

 

You would see a big increase in off the line torque,and the motor will rev more at touring speedgoing from a 66 to 70 tooth.

 

Changing from a 66 to a 70T will gear it down so the engine will rev higher on the hwy but you will get an increase in Torque. I would try it and see if you like it better I assume you have the 6 speed tranny which is higher geared to start with. On the older bikes it's a 32 tranny beltsprocket and a 70 or 65 T rear sprocket. I'm not sure which tranny sprocket your bike has but if it's a 32 then you would have to go to a 34 to retain the same ratio. just divide 66 by 32 which gives you 2.06 ratio if you divide 70 by 2.06 it works out to 33.9 or 34 teeth. On the newer bikes I believe the engine primary chain sprocket is already a 34 on the primary so there isn't enough room to put a larger sprocket to gear up the primary drive.

 

You would need a 139 tooth belt and a 32 tooth drive pulley to make it have the same gear ratio. Harley pulleys with 66 teeth use a 137 tooth belt.

 

My 1990 Glide had a 61T stock, being an International model. I have subsequently changed it to a US stock 70T. The effect of making that sort of change is to increase torque, in your case by 70/66 ie by 6% over what you have at present. It will also increase your engine revs by the same amount.

That is no loss, as all Harleys are way over-geared, largely to meet noise regulations. When you are travelling at say 3,000rpm at present, after you change gearing your revs at the same road speed will be 3,181rpm.

I also changed the gearing on my 03 Dyna at the compensator, from 25T to 21T, which is much more radical. I suggest your 70T will be fine.

 

Are you saying that you didn't change the belt going from 66 to 70.? I have a pulley coming and I really don't want to change that belt