Rear belt pulley?

[oneuptom]

FLST 1986-1999

FXST 1986-1999

FL 1979-1984 4-speed

FX 1979-1984 4-speed

The Pulley I need a measurement from is used on these bikes. Thanks!

What is the distance from the outer rim face to the bolt holes pad?



I'd like to get this 1 1/2" pulley from V-Twin and cut it down from 1 1/2" to 1" to use on a late Sportster. I can't cut down a 61 tooth pre-2015 Sportster pulley because there isn't enough offset and I don't want to space it. The later post 14 Sportsers have .390" more offset built into the pulley. I need something geared high enough to stay well ahead of interstate traffic while not spinning the motor higher than need be.

[TriNortchopz]

What size is your front pulley? maybe a larger one there, 30T to replace original 29T, if not running the larger one now;

40379-04 is 28 Tooth and Fits 2004-Present Sportster - Stock for 883cc

40409-04 is 29 Tooth and Fits 2004-Present Sportster

40380-04 is 30 Tooth and Fits 2004-Present Sportster

https://sportyparts.com/products/final-drive-front-pulley

these guys saying the rear pulley is common from 2007+, and available in 61, 66 and 68T:

Rear pulley for evo sportsters. 1991-2006 uses a 1.125" belt. 2007 to present uses a 1" belt.

https://sportyparts.com/products/rear-drive-pulley?pr_prod_strat=copurchase&pr_rec_id=e2b8c6cb2&pr_rec_pid=6711469834282&pr_ref_pid=6867427852330&pr_seq=uniform

and here, same part #s (except for 48):
For 2007-2015 - OEM 61T Sprockets

40350-07 is 68T BLACK w/highlights
40444-07 is 68T BLACK (Nightster / 883 Iron)
40353-08 is 68T BLACK (883 Iron / 48)

For 2016-2022 - OEM 61T Sprockets

40350-07 is 68T BLACK w/highlights
40444-07 is 68T BLACK (Nightster)
42200121 is 68T BLACK (48)

http://sportsterpedia.com/doku.php/techtalk:evo:transfinal01

This may be of interest:

Rear Pulley - Replace/Refurb

SuperMax Belt Drives

SuperMax produces belt drives, polyurethane pulleys and parts made to order out of a small facility in Cottonwood, Arizona. In addition to replacement parts, they also offer a refurbishment of rear belt drive pulleys.

Advertising info: SuperMax is proud to offer the worlds only option to repair worn out metal rear wheel pulleys (as shown on left).
SuperMax can replace the teeth on most factory and aftermarket 61, 64, 65 and 70 tooth rear wheel pulleys, increasing their life span . . . indefinitely!
SuperMax can remove the old teeth from your old pulley and overlay new proprietary “space age” poly teeth on your pulley to retain your current pulley design.
SuperMax also makes many specialty drives, including final drive kits for chain drive FXRs and FLTs, final drives for Sportsters and big twins, as well as super light tranny pulleys.
from here: http://sportsterpedia.com/doku.php/t...f:transfinal01

SuperMax Overlays Division
"These pulleys should outlast the motorcycle, as long as the recommended tension and alignment are maintained. Many customers ask, "How far will your pulleys go?", and our answer is ... "We still don't really know!".
Send your worn and noisy pulley to SuperMax, and we will perform the conversion for you."

http://www.supermax.net/Pages/Overlays.php

http://www.supermax.net/

maybe something here:

https://www.883sportster.com/whichpulley

[oneuptom]

Wow!.. Thanks for all that man!

I think my trans pulley is 29 teeth now, rear 68, for a 3.517 (overall) final. I'm thinking a 61 rear and a 31 trans for a 2.952 (overall) final
This would be an almost identical ratio as my Dyna in 6th-overdrive gear. If I can get a 32 on the trans without surgery I'll do that for even more.

That V-Twin 61 tooth pulley I posted I think was used on FXRs 1987-1994, HDI International Export models.

I was just over at a guys shop who is into FXRs, he had three up on lifts and was converting them to dual piston calipers. He was showing me how he modifies the swingarms to fit the new calipers so I asked him to measure the width, was 9 5/8". I never thought to look at how close the pulley was spaced from the swingarm. He gave me a 99 Sportser 61 tooth rear to try, but I saw the offset was wrong when I l measured it. My Sportster swingarm is also 9 5/8" wide and the pulley face is .200" from the arm. The factory moved everything over when they started shipping Sportsters with a 150 tire. My guess is that FXR pulley is spaced almost identical from the swingarm as these late 150 tire Sportsters.

I have a 29 tooth pulley for a 4spd Evo XL I got from Supermax and also a 51 rear that I can't find at the moment. You get older and can't remember shit! To be honest, I wasn't impressed with Supermax's work, but that was long time ago.

[oneuptom]

When I get busy I'll use this chart to make a pattern, see if I can get a 32 in there, and to know for sure what pulley I should order from evolution-industries.

https://www.evolution-industries.com/shop/harley-davidson-motorcycle-parts/power-drive-sprockets-chains-and-pulleys/transmission-pulleys/power-drive-aluminum-transmission-pulleys/

https://www.pfeiferindustries.com/documents/14mm%20HTD%20Timing%20Belt%20Pulley%20PD%20and%20OD%20Chart.pdf

[TriNortchopz]

a blank pulley would allow custom # of tooth choices:

Motorcycle Rear Pulley Blanks

Our pulleys start from a solid bar of prime 6061 aluminum... Once they are forged, they are machined into the pulleys. The teeth have the true gear-cut that exceed the RMA standards for a perfect fit...
We stock the most popular sizes, but we actually have over sixteen (16) sizes.
Being U.S.A. forged and machined, it allows us to do custom sizes too.

https://www.msiwheelblanks.com/pulleys.html

Trivia:

Did you know that the very first Harley-Davidson that was produced in 1903 featured belt drive? Ten years later, they offered the chain drive. Not until 1980 did you see a new H-D model featuring the belt drive again!

[oneuptom]

Maybe I'll talk with them to see if the teeth are hard anodized, and it would be nice to have pulley spokes machined to match my wheel. I would bet quite pricey though!!

From what I can gather the V-twin pulley teeth are hard anodized, so easy to narrow without worrying about chipped chrome like if it was a factory pulley you were cutting. They all, V-Twin (no matter who is selling them) come from the same Taiwan factory that supposedly meets this standard. I've never purchased from V-Twin before but hear they have a very easy return policy. Tomorrow I'll go back over to Marshall's shop and measure a FXR pulley

https://www.engineersedge.com/belt_design/timing_belt_pulley_tolerances_15345.htm

[docmel]

A +1 or -1 tooth count in the trans or rear pulley can make a huge drivability issue.

Do you want a stoplight to stoplight driver or one for the highway?

You mentioned:

I think my trans pulley is 29 teeth now, rear 68, for a 3.517 (overall) final. I'm thinking a 61 rear and a 31 trans for a 2.952 (overall) final. This would be an almost identical ratio as my Dyna in 6th-overdrive gear. If I can get a 32 on the trans without surgery I'll do that for even more.

Remember, it isnt just about the trans to rear pulley ratio or what you end up with in your final gear: Its also about how your tranny is geared in ALL gears: A sporty and Dyna dont have the same transmission gear ratios, hence your final ratio qoutes might not be accurate: You could end up wth a really off final drive ratio, or really weird and undrivable ratios between each or at least between some gears

Consider what transmission ratios you are running in your gear box as well as the final tranny to rear pulley ratio you will actually end up with

Also, consider you are going to have an issue with belt fit: Not many choices out there: Your size choice of a trans pulley may not fit as well

[docmel]

One last consideration: Rear belt tension adjustability: Just a few teeth larger or smaller, you can run out of adjustment room in the rear axle slot adjusters. And as mentioned, available belt sizes out there might limit your final choices

I became VERY educated the hard way on figuring out a realistic final drive ratio on my pan, ratchet top 4 speed with rear belt drive: But it was easy compared to yours because I knew the transmission gear ratios. (I believe you can find yours in any HD forum) . But the rear belt was a bitch to find because of the limited belt sizes out there (both in width and length) and the limited range of adjustment in the rear axle slots

Once you find your tranny gear ratios, use them to figure out what your real rear belt ratio actually comes out to in each gear based on the tranny and rear pulley sizes you want to run

Have to ask, what is your final overall goal here?

[oneuptom]

Have to ask, what is your final overall goal here?

I have a first year 6spd Street Bob with the 88 motor in it, 2.790 final in 6th.
I spend time on I-40 between SoCal and N AZ. I try not to keep my speed below 80mph, usually 85-90 and at 90 for long stretches the motor is at the edge of it's comfort zone. And with the 2.25 tank on the Sportster I'm looking at at least that much gearing to be happy.

My only problem with this belt gearing was finding a rear pulley with the correct offset, why I need to cut a 1 1/2 wide pulley down to 1".

Anyway for now, I've decided to covert a 4.5 x 17 rear ducati mag from cush drive to solid drive so I can run some nice radials on it with a 520 chain, then my gearing can be whatever I want.

[TriNortchopz]

I see they make a belt tensioner for rear belt drives, so this could help with sizing and tension of different length belts; you could make one even, similar to what is used for chain drives:

https://www.arhcustom.com/product/free-spirits-belt-tensioner-in-black-finish-for-harley-davidson-2004-2020-sportster-models-207665k

I looked and found 1" belts available in: 126, 130, 131, 132, 133, 135, 136, 137, 139, 140, 151 and 166 & 168 tooth. A belt length calculator found online will help determine length needed.

https://www.arhcustom.com/brands/gates/gates-final-drive-belts/

https://motorbikeinsider.com/harley-davidson-drive-belt-size-chart/

[oneuptom]

Apparently these latest carbon fiber 1" belts are twice as strong as the original 1.5" Kevlar belts? What Harley says anyway

[docmel]

You gotta get away from qouting "I have a first year 6spd Street Bob with the 88 motor in it, 2.790 final in 6th"

It really has nothing to do with your sporty. Again, as I posted earlier, you need to find what your SPORTY gear ratios are, and configure you final pulley ratio based upon that. Your street bob has nothing to play into this


You can make, adapt, configure all you want in a fornt and rear pulley, but you need to focus on your sporty gear ratios. You are asking for allot of $$ spent, and will most likely get poor and unridable ratios in the end if you dont

I prefer belt over chain, but then again, this type of work was so much easier and cheaper with chains and sprockets

Yes, there are belt tensioners you can use for too long belts. But they dont take up that much slack: But it is a way: Get a slightly longer belt if thats all thats available and use a tensioner

Belts are very expensive: Choose wisely as most will not take returns once installed

[docmel]

Another point: Belts not only come in dif widths and lengths, they also come in diffent tooth pitches. So do pulleys. Be sure you connect the dots.........

[docmel]

OP Any luck so far?

[rockman96]

Lots of good info in this thread!