Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
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Road Warrior
Joined: Jun 2006
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From: NH
Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
I wanted to report back about the 3.37 primary gear setup upgrade.
It has been said that the RPM on the highway would go up by about 200/300 RPM @ 70 MPH. After the install, 70 MPH I have about 3050 RPM (just under 3100).
At first, I really didn't notice a big change in 1st or 2nd gear. But the acceleration was better. Now after logging in some miles, I found that the gearing had other benefits as well.
1 - You are able to cruise at a lower RPM without chugging or lugging the motor. In stock form, I always wanted to stay above 2000 RPM because anything less than that made no power or the bike shook more. NOW, I can cruise at 1500 or just above that in RPM without lugging the motor. It doesn't seem like it makes sense, but since the bike doesn't have to work hard to come upin RPM or maintain RPM, the motor doesn't shake. I can cruise 30 MPH in 5th on somewhat level surface. The best part is I really don't need to downshift to accelerate either!!!!!
2 - Gas mileage has increased! Again, this sounds like it wouldn't make sense because a higher RPM at speed makes you think you would eat up more gas. But reality is that I can go up one gear and lower my RPM's in the lower speed limit sections. I am now at a 1/2 tank and put on 127 miles. As a comparison, I filled my wife’s deluxe and my bike together, and she is not at 1/4 of a tank. And we rode together all day.In stock form,I would be just under 1/4 tank and she would be just about or above 1/4 of a tank.
3 - Less shifting - again, my wife rode with me today on her Deluxe and when we came to a larger hill, she would sometimes down shift because her bike was lugging. I was fine by twisting the grip - no down shift needed!
4 - Better cruising speed/gear choice - In stock form, I had issues with 45 MPH and 35 MPH zones. It seems at 45 MPH that 4th gear was too high in RPM, and 5th made the motor work hard.
Sorry to rant. But if you were not sure about doing it, don’t hesitate! It was one of the best mods I’ve done!
- Denis
It has been said that the RPM on the highway would go up by about 200/300 RPM @ 70 MPH. After the install, 70 MPH I have about 3050 RPM (just under 3100).
At first, I really didn't notice a big change in 1st or 2nd gear. But the acceleration was better. Now after logging in some miles, I found that the gearing had other benefits as well.
1 - You are able to cruise at a lower RPM without chugging or lugging the motor. In stock form, I always wanted to stay above 2000 RPM because anything less than that made no power or the bike shook more. NOW, I can cruise at 1500 or just above that in RPM without lugging the motor. It doesn't seem like it makes sense, but since the bike doesn't have to work hard to come upin RPM or maintain RPM, the motor doesn't shake. I can cruise 30 MPH in 5th on somewhat level surface. The best part is I really don't need to downshift to accelerate either!!!!!
2 - Gas mileage has increased! Again, this sounds like it wouldn't make sense because a higher RPM at speed makes you think you would eat up more gas. But reality is that I can go up one gear and lower my RPM's in the lower speed limit sections. I am now at a 1/2 tank and put on 127 miles. As a comparison, I filled my wife’s deluxe and my bike together, and she is not at 1/4 of a tank. And we rode together all day.In stock form,I would be just under 1/4 tank and she would be just about or above 1/4 of a tank.
3 - Less shifting - again, my wife rode with me today on her Deluxe and when we came to a larger hill, she would sometimes down shift because her bike was lugging. I was fine by twisting the grip - no down shift needed!
4 - Better cruising speed/gear choice - In stock form, I had issues with 45 MPH and 35 MPH zones. It seems at 45 MPH that 4th gear was too high in RPM, and 5th made the motor work hard.
Sorry to rant. But if you were not sure about doing it, don’t hesitate! It was one of the best mods I’ve done!
- Denis
Elite HDF Member
Joined: Mar 2006
Posts: 4,722
Likes: 5
From: Biddeford, Maine
RE: Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
What year did they change the gearing.......2003?
What's the total cost to do the swap? How long did it take you?
Steve
What's the total cost to do the swap? How long did it take you?
Steve
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Road Warrior
Joined: Jun 2006
Posts: 1,797
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From: NH
RE: Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
ORIGINAL: maineultraclassic
What year did they change the gearing.......2003?
What's the total cost to do the swap? How long did it take you?
Steve
What year did they change the gearing.......2003?
What's the total cost to do the swap? How long did it take you?
Steve
Not sure what year they changed over, I think it was '03.
I ordered the parts from Zannotti's and it was just under $400. It took about 3 hours if you take your time, including reading the manual. Very easy to do!
Thread Starter
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Road Warrior
Joined: Jun 2006
Posts: 1,797
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From: NH
RE: Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
In case anyone needs the info:
The clutch basket part # is 37846-99A 37 tooth. The motor sprocket is #40269-85A 24 tooth.
The clutch basket part # is 37846-99A 37 tooth. The motor sprocket is #40269-85A 24 tooth.
Thread Starter
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Road Warrior
Joined: Jun 2006
Posts: 1,797
Likes: 0
From: NH
RE: Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
ORIGINAL: dawg
I thought it wasn't worth it if you do a lot of highway riding because you'd rev too high?
I thought it wasn't worth it if you do a lot of highway riding because you'd rev too high?
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Tourer
Joined: Dec 2006
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From:
RE: Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
i did it on my 01 dyna and it was a good bang for the buck...now, if it could be done to the 07s, i would jump on it...i hope the parts will soon be available...
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Joined: Feb 2005
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From: Twin Cities Minnesota
RE: Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
ORIGINAL: dawg
I thought it wasn't worth it if you do a lot of highway riding because you'd rev too high?
I thought it wasn't worth it if you do a lot of highway riding because you'd rev too high?
Not at all, the rpm difference is very minor; however you can feel the difference. A worth while change. For anyone doing it add the automatic primary chain tensioner at same time and p.s. you could swap in the chrome inner primary for no additional labor cost when doing swap.
Thread Starter
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Road Warrior
Joined: Jun 2006
Posts: 1,797
Likes: 0
From: NH
RE: Doing a 3.37 primary gearing setup, DO NOT hesitate! Do it!
ORIGINAL: jeepster09
Not at all, the rpm difference is very minor; however you can feel the difference. A worth while change. For anyone doing it add the automatic primary chain tensioner at same time and p.s. you could swap in the chrome inner primary for no additional labor cost when doing swap.
ORIGINAL: dawg
I thought it wasn't worth it if you do a lot of highway riding because you'd rev too high?
I thought it wasn't worth it if you do a lot of highway riding because you'd rev too high?
Not at all, the rpm difference is very minor; however you can feel the difference. A worth while change. For anyone doing it add the automatic primary chain tensioner at same time and p.s. you could swap in the chrome inner primary for no additional labor cost when doing swap.
