Wondering about changin' my rear pulley

[Monk]

I read an article that stated if you change the rear drive pulley to a 55 notch setup, it'll lower the RPMs by about 300 @ 70 on the interstate.

If a Sportster has 29-tooth front and 61-tooth rear belt pulleys (like most stock 1200's), the engine will be turning 2500 rpm at 55 MPH, 2950 rpm at 65 MPH, and 3400 rpm at 75 MPH. Change to a 55-tooth rear pulley (keeping the 29-tooth front pulley), and the engine will be turning 2250 rpm at 55 MPH, 2650 rpm at 65 MPH, and 3050 rpm at 75 mph.

Then Osco asked "What would you need to do to correct the speedo..?"

Extremely good question!

Anyone?

Anybody?

[MrMarty51]

GPS or check with the dealer when You order the pulley,they should be able to tell You whut gear for the speedo drive You need to change to get a correct reading.
It should not be a big job to change out the speedo gear in the transmission.

[DevilDog]

Monk,

If you want to correct the speed off set you will need this...

http://www.dakotadigital.com/index.c...rod/prd238.htm

[MrMarty51]

Monk,

If you want to correct the speed off set you will need this...

http://www.dakotadigital.com/index.c...rod/prd238.htm

That looks like a nice little tool and the price is`nt too bad either and it is "MADE IN THE USA".

[Monk]

Thanx Dog! That looks like just the ticket... maybe even get that OEM dual tach/speedo in one can for it, too (I mean... as long as I'm workin' on it anyway). That'd be sweet.

[DevilDog]

Thanx Dog! That looks like just the ticket... maybe even get that OEM dual tach/speedo in one can for it, too (I mean... as long as I'm workin' on it anyway). That'd be sweet.

NP Monk.... let us know how it works out.

[Crocodile56]

Why would you want to do that.......it will give you less power off the line!!!

[Monk]

Jes' t'be contrary...

[kc5gxc]

I changed my front pulley from 28 to 30. Think the pulley was about $55. I sure like it. No tach, but runs easier at hiway speeds. When speedo is showing 55, I am really going 60. I just remember that.
Also the odometer is off....shows less miles per trip. I made a factor that I can use to figure gas mileage...getting 55 mpg or better now. No problems at low speed...but never ride 2 up on it.
I heard the rear pulley is much more expensive than the front......also...I used same stock belt with no problems at all.
Good luck.....Pete

[Monk]

Good point about the belt... would I need one 6 nubs shorter..?

[Osco*]

Why would you want to do that.......it will give you less power off the line!!!

Yeah Monk,,why do you want to do it ?? Mileage ?? Vibrations ??
If Its Vibes gettin thru maybe your rubber engine mounts need adjusting, Been told the front lower one can need a turn or two,,I dunno,,
Of course 3,000 at 75 would be nice,,,
If I ever win the lottery I'm gonna get a Six speed OD for my custom built Sporty XD

[Monk]

I'm just wishin' I could lower RPMs on I-95... I try to avoid too much interstate riding anyhow, I find it tiring. Maybe the Mustang will help that.

No the bike has fantastic power off the line and great torque - it's scary, doesn't need changed at all. I'm just lookin' into all the possibilities around.

[Osco*]

I'm just wishin' I could lower RPMs on I-95... I try to avoid too much interstate riding anyhow, I find it tiring. Maybe the Mustang will help that.
No the bike has fantastic power off the line and great torque - it's scary, doesn't need changed at all. I'm just lookin' into all the possibilities around.

Yeah The seat will help, For me the wind blast at 75-80 mph was wearing me out and because of that I was hangin on by the Bars, bike didn't like that.
The quarter fairing really changed things, I could relax my arms an grip and let the bike do It's thing.
Sportsters are a bit more of a workout on the big road. An hour Is about my limit for comfort at those speeds, Then Like you said, I gotta get off an get the
blood back in my ass.
My shocks are my next focus cause I can ride for hours at 60 or below.
Something Dave said, "The Stock shocks are too slow" an yep he's right,,damping Is too slow so either the back end "Packs" a bit,,which hurts,,or It over extends and Is topping out.
All this Unnecessary movement translates into fatigue. I am not trying to make a touring bike outta my R model but so far most everything I've done extends my ride time before my comfort level falls and makes me need a break.

I do think there Is plenty of power In these 1200's to pull big speed at 3100 rpm's.

[Juiced]

This is all very interesting as I am trying to raise the RPMs to get into the "sweet spot" when riding the highway. Right at my shift
points is where I have it the smoothest. I do tend to shift a bit low.


Ed

[sonnyd]

Yeah lowering the rpm's on the highway ain't a bad idea especially if your running in that 75-80 range. Went out to the
dealer up North about a month or so ago to see Jackyl and we were running in that range. Man, my butt was Burning from
the vibration. Something really happens between 70 and 75, she turns into a Vibration machine.
Regards Sonny