The belt to chain drive conversion thread
Cruiser
Joined: Dec 2006
Posts: 148
Likes: 14
From: Just North of Inverness,Scotland
Here's a couple of pictures of the belt.
Cruiser
Joined: Feb 2013
Posts: 185
Likes: 2
From: Weymouth, Ma
My experience
2014 street bob. Zippers kit 25-53
25t up front helps with clearing the passenger peg mount no problems.
Before going chain I did a 30t front pulley and loved the gearing. It was perfect for me. I feel 25/53 is spot on
2014 street bob. Zippers kit 25-53
25t up front helps with clearing the passenger peg mount no problems.
Before going chain I did a 30t front pulley and loved the gearing. It was perfect for me. I feel 25/53 is spot on
Intermediate
Joined: Jun 2015
Posts: 39
Likes: 0
From: New Jersey
hey lama i can really use your help.. if you can answer a few questions for me i would owe you big time! i have a 2016 street bob pretty much in the same boat you were when converting to chain drive i need a 7/8 spacer with a .500 offset got that all figured out. im running 13.5 works performance shocks my number one concern is how much rub do you get from the chain? i know bung king makes sliders but im worried about eating them up all the time just seems like a pain, everyone tells me i wont rub but looking at your pics that looks close! also im going to order the arp bolts i know there 7/16 but can you give me the exact size? im trying to do this with little to no down time. one again if you can answer my few questions it will be greatly appreciated. last question is i know your speedo was off but does it throw the tachometer off as well? thank you!!
Intermediate
Joined: Jun 2015
Posts: 39
Likes: 0
From: New Jersey
.875" (7/8") Vulcan Spacer arrived (FAST!) today, so its time to reassemble. Now = perfect chain alignment. This is THE spacer for a 2006+ bike using a .500" offset front PBI sprocket:
Ok, here's a little bit of an issue. The underside of the chain as it passes through the top run of the primary case comes millimeters close to rubbing a support casting of the outer to inner primary case. This is very evident as I am using a 24T front sprocket. Also having 13.5" rear shocks exaggerates the chains path towards this lug. It will without doubt rub this aluminum casing:
Ok, here's a little bit of an issue. The underside of the chain as it passes through the top run of the primary case comes millimeters close to rubbing a support casting of the outer to inner primary case. This is very evident as I am using a 24T front sprocket. Also having 13.5" rear shocks exaggerates the chains path towards this lug. It will without doubt rub this aluminum casing:
hey lama i can really use your help.. if you can answer a few questions for me i would owe you big time! i have a 2016 street bob pretty much in the same boat you were when converting to chain drive i need a 7/8 spacer with a .500 offset got that all figured out. im running 13.5 works performance shocks my number one concern is how much rub do you get from the chain? i know bung king makes sliders but im worried about eating them up all the time just seems like a pain, everyone tells me i wont rub but looking at your pics that looks close! also im going to order the arp bolts i know there 7/16 but can you give me the exact size? im trying to do this with little to no down time. one again if you can answer my few questions it will be greatly appreciated. last question is i know your speedo was off but does it throw the tachometer off as well? thank you!!
Extreme HDF Member
Joined: Jun 2014
Posts: 11,448
Likes: 2,299
From: NW Ohio
Stock screw:
SCREW 7/16-14 X 2-5/8 HEX CAP W/WASHER, LOCK PATCH
If you can measure the mounting flange thickness of the current belt pulley, you can subtract that dimension from 2.625 to get the thread engagement. Add the thickness of the new sprocket (.5, iirc) plus the adapter thickness (.875) to the thread engagement and you've got your answer.
The tach reads engine speed irrespective of gearing or tire diameter. It will be accurate for measuring engine speed, but not estimating the old ground speed. ie, if 2500 rpm = 65 mph in 6th with the belt, it WON'T be 2500 @ 65 with different final gearing. Either use GPS or an aftermarket speedo that can be calibrated.
SCREW 7/16-14 X 2-5/8 HEX CAP W/WASHER, LOCK PATCH
If you can measure the mounting flange thickness of the current belt pulley, you can subtract that dimension from 2.625 to get the thread engagement. Add the thickness of the new sprocket (.5, iirc) plus the adapter thickness (.875) to the thread engagement and you've got your answer.
The tach reads engine speed irrespective of gearing or tire diameter. It will be accurate for measuring engine speed, but not estimating the old ground speed. ie, if 2500 rpm = 65 mph in 6th with the belt, it WON'T be 2500 @ 65 with different final gearing. Either use GPS or an aftermarket speedo that can be calibrated.
Last edited by cggorman; Mar 2, 2017 at 11:10 PM.
Intermediate
Joined: Jun 2015
Posts: 39
Likes: 0
From: New Jersey
Stock screw:
SCREW 7/16-14 X 2-5/8 HEX CAP W/WASHER, LOCK PATCH
If you can measure the mounting flange thickness of the current belt pulley, you can subtract that dimension from 2.625 to get the thread engagement. Add the thickness of the new sprocket (.5, iirc) plus the adapter thickness (.875) to the thread engagement and you've got your answer.
The tach reads engine speed irrespective of gearing or tire diameter. It will be accurate for measuring engine speed, but not estimating the old ground speed. ie, if 2500 rpm = 65 mph in 6th with the belt, it WON'T be 2500 @ 65 with different final gearing. Either use GPS or an aftermarket speedo that can be calibrated.
SCREW 7/16-14 X 2-5/8 HEX CAP W/WASHER, LOCK PATCH
If you can measure the mounting flange thickness of the current belt pulley, you can subtract that dimension from 2.625 to get the thread engagement. Add the thickness of the new sprocket (.5, iirc) plus the adapter thickness (.875) to the thread engagement and you've got your answer.
The tach reads engine speed irrespective of gearing or tire diameter. It will be accurate for measuring engine speed, but not estimating the old ground speed. ie, if 2500 rpm = 65 mph in 6th with the belt, it WON'T be 2500 @ 65 with different final gearing. Either use GPS or an aftermarket speedo that can be calibrated.
Last edited by 96sled; Mar 3, 2017 at 06:42 AM.
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Extreme HDF Member
Joined: Jun 2014
Posts: 11,448
Likes: 2,299
From: NW Ohio
thank you sir I'm new here so it's been kind of rough getting answers from anyone .. was also hoping to find out about the chain rub issue. I'm hearing mixed opinions. I'm ordering everything and I'm just happy trying to have as little downtime as possible. If I went 25-60 instead it 24-55 would that get me more clearance ?
Intermediate
Joined: Jun 2015
Posts: 39
Likes: 0
From: New Jersey
I'm sorry, but I can't answer the slider question. My bike is an old 5 speed and doesn't have that issue. I run without a slider. That said, the slider is on the slack side of the chain so it won't see the kind of wear that an actual tension would. It just keeps metal/metal contact from happening. I wouldn't expect much wear on it, but honestly that's just a hunch on my part.