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Hey anyone interested , best mod to date I changed the front pully to 31 tooth from a Stryker. Totally changed the ride quality all around. Still feels torquey as hell . Great investment
Wow! I didn't know that this was even an option. Ok. What are we talking here? More top end? How many teeth are on our stock SCRs? Jevers
 

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Discussion Starter · #3 ·
Wow! I didn't know that this was even an option. Ok. What are we talking here? More top end? How many teeth are on our stock SCRs? Jevers
Stock scr is 30 teeth. You get a little more top end on highway and lower rpms about 3-4 hundred at speed . Really don’t notice any power loss down on the bottom end . Did notice way better fuel economy
 

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Stock scr is 30 teeth. You get a little more top end on highway and lower rpms about 3-4 hundred at speed . Really don’t notice any power loss down on the bottom end . Did notice way better fuel economy
Thanks for the info and with the high price of premium gas, it should only take a few fill ups to recoup the investment! Jevers
 

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If I did the math correctly, changing from a 30 tooth front sprocket to a 31 tooth sprocket will result in a 3.3% overall taller gear ratio. Since the SCR gets its speed reference from the transmission end and not the rear wheel end, I think that the overly-optimistic stock speedometer would see a 3.3% error correction and read closer to reality. The stock speedo has about a 6% error from the factory at around 55 mph. I believe. Another plus for this mod. If I'm not thinking this through correctly, let me know.
 

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Discussion Starter · #6 ·
If I did the math correctly, changing from a 30 tooth front sprocket to a 31 tooth sprocket will result in a 3.3% overall taller gear ratio. Since the SCR gets its speed reference from the transmission end and not the rear wheel end, I think that the overly-optimistic stock speedometer would see a 3.3% error correction and read closer to reality. The stock speedo has about a 6% error from the factory at around 55 mph. I believe. Another plus for this mod. If I'm not thinking this through correctly, let me know.
Yes your calculations are correct. It feels like totally different bike . I was unable to locate a used pully so I bought a new one @ $210.00 .At first I was unsure but after about 100 miles I fell in love.
 

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This sounds incredible! I just finished a 1,500 mile trip and I would've loved to have more top end! It seems I'm always looking for the 6th gear. Looking for a gear I know I don't have seems to be a habit I just can't break..
 

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My personal opinion is 31 is the number . It’s hard to describe but it feels right at 31 . $210 seems steep but it’s hard to describe. I’ve done just about every mod on the site and this is the one that rocked my world .
I'm wondering if this swap would have a negative impact on Ivan's reflash and the intake and exhaust mods that I've made 🤔 😳? Jevers
 

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Okay gents, I have been doing some reading on the v star forum and another mod is the front pulley from a Yamaha Road Warrior. PN SPX-17651-00-00. It's a 32 tooth and this will require some shims or washers and a slight modification of the speed sensor bracket.No change in belt. Also the rear pulley can be swapped to a Harely Softtail PN 40315-94. This is 65 tooth from the stock 70. I think I am going to try this.
 

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Discussion Starter · #13 ·
I'm wondering if this swap would have a negative impact on Ivan's reflash and the intake and exhaust mods that I've made 🤔 😳? Jevers
I have Ivan’s,a pipe and intake and it has done nothing but enhance all the other mod’s .It took all of 15 minutes . Here’s a pick of my bike and part # for pulley
Wheel Tire Land vehicle Fuel tank Plant

Wood Bumper Shelving Audio equipment Wood stain
Wood Bumper Shelving Audio equipment Wood stain
Wheel Tire Land vehicle Fuel tank Plant
Wood Bumper Shelving Audio equipment Wood stain
 

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I’ve looked for this pulley on eBay and have come up short, are there any other models that use the same front pulley? I’m seeing some pulleys from the Yamaha Raider and multiple variations of the XVS, they’re all 31T.
Does anyone know if these are an acceptable alternative?
 

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My personal opinion is 31 is the number . It’s hard to describe but it feels right at 31 . $210 seems steep but it’s hard to describe. I’ve done just about every mod on the site and this is the one that rocked my world .
Very tempted to try
$195 on partzilla .... Yamaha 27D-17651-00-00 - BELT PULLEY | Partzilla.com
Does it just fit, or does one need to make other mods ?

Thx
 

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It's 3AM, I'm bored so I did some math for all the different conversions you could do. This is a list of sprocket sizes and the percent difference they would make
31/70= 3.2% ^
32/70= 6.5% ^
30/65= 7.7% ^
31/65= 11/1% ^
32/65= 14.6%^
^ Means the rear sprocket speed increases by this percentage meaning the overall speed output to the wheels increases by that percentage.
 

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Hey anyone interested , best mod to date I changed the front pully to 31 tooth from a Stryker. Totally changed the ride quality all around. Still feels torquey as hell . Great investment
Well, after sipping on the perverbial 31 tooth Kool-aid and contemplating whether the $225 investment was worthwhile, it finally dawned on me. Having owned a number of dual sports ( enduros for us old timers ), I often changed the front sprocket to a 1 tooth smaller one. It has transformed those bikes into a real dirt bikes. So, having the day off, I decided to make the switch. It's a very easy swap, but the pickup for the speedo ends up being VEERRYY close. So close that I was afraid that it would wear against the bigger sprocket. I removed the bracket, unplugged it and also removed the 1 screw that holds the pickup in the holder. I then pushed the pickup out of the holder with my thumb just far enough to slip a flat washer in between the pickup and the holder. Now the face of the pickup is up inside of the holder out of harms way. The holder could still rub, but the pickup is safe and yes it still works. After a brief shakedown run, I felt the difference right away. Much smoother with less vibration. Just like women, the longer the legs, the better! FWIW, I ended up backing off the adjusting bolts 6 full turns to get the new sprocket on. Then I turned them in 3 and 1/2 turns. So that means I loosened up the belt 2 and 1/2 turns to accommodate the larger sprocket. Hope this helps. Jevers
 
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