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Author Topic: Chain Conversion  (Read 6541 times)

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Offline JS52

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Chain Conversion
« on: January 29, 2018, 04:00:47 pm »
Hey guys,

Was playing with the idea of doing a chain conversion for the bolt.. I guess the question is what sizing do you guys think would be best? I know a few guys have talked about making it a bit wider for highway but obviously If I draw these up and have them cut I will have to make more than 1.

I believe 41 is the biggest you can go up front so my guess would be to leave the front at a 40 and the back at a 66-68, what are your guys' thoughts? and would anyone be interested in them?

As of right now it is just an idea so nothing is in place yet..



Offline lunkhead

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Re: Chain Conversion
« Reply #1 on: January 29, 2018, 11:59:58 pm »
I think you're way off on the ratios and tooth count. Stock is 70 rear and 30 front (2.33:1) so you might want a ratio of around 2.3:1 to 2.2:1. An R1 front has the same 13 spline hole so you could try an off the shelf 16 tooth front with a custom made 35-37 rear from Spocket Specialists. You'll also need to make something for your speedo sensor to read.
C-SPƎC

Offline SLCBolt

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Re: Chain Conversion
« Reply #2 on: January 30, 2018, 12:17:45 am »
A dude on the Bolt Facebook page just finished the conversion. Might be worth hitting him up

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Offline A.T.

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Re: Chain Conversion
« Reply #3 on: January 30, 2018, 07:12:57 am »
If not for a custom build, why?  I guess I could see this on the Scrambler but what would be the benefit on the street? 
 

Offline lunkhead

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Re: Chain Conversion
« Reply #4 on: January 30, 2018, 07:47:50 am »
You could use longer shocks with much more travel for comfort, more lean angle and better control/traction over bumps.
C-SPƎC

Offline JS52

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Re: Chain Conversion
« Reply #5 on: January 30, 2018, 01:38:13 pm »
You could use longer shocks with much more travel for comfort, more lean angle and better control/traction over bumps.

Ya, I haven't really looked into the numbers but I just wanted it a bit wider so its not sitting at 4K on the highway at 80.

Offline ChopperCharles

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Re: Chain Conversion
« Reply #6 on: January 31, 2018, 02:02:27 am »
Lunkhead, you can already use longer shocks for more lean angle. I'm running 12.25" FORSA-brand shocks made for a Sportster on my SCR950. The trick is, they have only 1/2" more travel than the stock shocks. That's enough to stay mostly inside the tension range for the belt.

For long-travel shocks you'll need a chain drive conversion or a tensioner pulley for the belt, like on a Buell. But to just swap shocks, you can increase ride height safely. The manual says to measure belt tension on the side stand. I did so with the stock shocks, and adjusted the tension to 6mm deflection with the 10 lb force gauge. I then removed the shocks, measured them precisely, measured the travel (amount of exposed piston), and moved the swingarm up with a bottle jack until the fully-compressed position was reached. I measured deflection there. 3mm with the 10lb tool. So when I installed the new shocks, I adjusted the deflection to 3mm at the fully compressed position for the new shocks. That turns out to be 9mm deflection when the bike is on the side stand. Spec is 6mm-8mm. 9mm is within the margin of error (rotate the wheel and the deflection will be a mm or two off in different sections of the belt), and is still quite tight. More than 1/2" of extra travel and you will need a tensioner pulley.

Note that 12.25" shocks are 1.75" over stock. I dropped the forks in the trees 0.25", so the rear ends up 1.5" taller than the front. Bike now handles like it's on rails, and there is AMPLE cornering clearance. It's honeslty a brand new bike. You will need to alter the bracket for the rear brake cable stay if you have stock exhaust, as it will contact the stock muffler hanger with 12.25" shocks.

Charles.

Offline lunkhead

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Re: Chain Conversion
« Reply #7 on: January 31, 2018, 09:01:14 am »
Chopper, I read you're other post about adding rhe longer shocks. Good info there! While it's true that adding length gives more cornering clearance while maintaining good belt tension, it's when you add a good amount of travel which aids in handling and comfort where you'll run into problems. Leaned way over (when handling is most important), the swing arm needs to move farther to react with bumps than it does straight up. If the tire isn't allowed to follow the road's bumpy surface, the whole rear end gets upset. Having the tire and not the whole bike react to the road surface requires a greater arc of the swing arm which is what will cause the biggest difference in belt slack.
C-SPƎC

Offline ChopperCharles

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Re: Chain Conversion
« Reply #8 on: January 31, 2018, 11:59:15 am »
I know that, and the extra 1/2" of clearance does make a big difference. My SCR used to bottom whenever I hit speed humps at 40mph. It doesn't anymore. There is more travel available. Having a *lot* more travel would be great, and I am designing a tensioner for the belt because of that. But the sportster shocks are giving me the cornering clearance I need, and performing better than stock boingers in every way. They're not the ideal shock because they don't have 4" of travel, but they're definitely better than what came with the bike. And holy bajeezus does my bike corner better now :)

Charles.

Offline lunkhead

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Re: Chain Conversion
« Reply #9 on: January 31, 2018, 06:10:56 pm »
I have the standard Hagons which works great even with a passenger. Not as drastic a change as your's but does the job. I don't lean far enough to touch the pegs so I gave up on the chain. The SCR should have a chain.
C-SPƎC

Offline ChopperCharles

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Re: Chain Conversion
« Reply #10 on: February 01, 2018, 01:20:00 am »
Yeah, if a chain conversion becomes available aftermarket, I'll probably snag it one day.

I can't reign it in enough to handle the bike with the stock length shocks. I was scraping undercarriage just turning onto side streets. Pegs would touch down only a microsecond before the actual footpeg bracket on the right side. I'm used to cafe racers and vintage bikes with miles of lean angle. Even my lowered V65 Magna has way, way more lean angle than the stock SCR. But now I've got plenty, and I'm looking forward to finding where the new limits are...

As soon as it's not blasted cold anymore!

Charles.

Offline ChopperCharles

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Re: Chain Conversion
« Reply #11 on: February 01, 2018, 12:19:13 pm »
So, if an R1 sprocket works for the front... what about swapping the rear CARRIER for one from another bike?  It'd take some sleuthing through partsfish.com, but any bike that uses the same part number for the rubber bumpers inside the carrier would likely fit the bolt. Then you can bolt on a sprocket for whatever bike that carrier came from and likely have a lot of options available. All you'd need to do at that point is machine a spacer for the axle, as the OEM pulley carrier has a big honkin' extension and another bearing in it, which wouldn't be needed anymore.

Charles.

Offline Lictor of Thrax

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Re: Chain Conversion
« Reply #12 on: July 02, 2020, 02:42:31 am »
Anyone looked into this more? I'm interested just to be able to be at lower RPMs while riding at highway speeds. Plus, I'm vain, and chain drives look cooler. (Before you say it... I know they're a lot more work).

Offline Sdaniels

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Re: Chain Conversion
« Reply #13 on: July 02, 2020, 09:17:13 am »
Anyone looked into this more? I'm interested just to be able to be at lower RPMs while riding at highway speeds. Plus, I'm vain, and chain drives look cooler. (Before you say it... I know they're a lot more work).

Look into putting the front pulley from the V-star 950 (I think).  It's one tooth less than the Bolt.  Wait, that's all wrong.  One tooth more & it's a Stryker pulley.
« Last Edit: July 02, 2020, 10:28:21 am by Sdaniels »
2015 C-spec

Offline Lictor of Thrax

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Re: Chain Conversion
« Reply #14 on: July 03, 2020, 06:11:37 pm »
What would be the advantage of using the stryker front pulley? Would that give me more torque?