1985 VF 500 14t or 15t on the front?

Hi everyone,

I searched high low and in between before posting this question, but if there is another thread that answers this questions for my specific bike, I apologize (and would appreciate the link). I just bought a 1985 Interceptor 500. The guy I bought it from told me that he'd switched the front sprocket from 15t original to a 14t. He says that with the 15 it is sluggish. From what I've read on here and other places, some people say that it's better to keep standard, some say gear it taller, and some say the modification the seller made is the way to go. I would really like to hear from people who have/had the same bike, and have experience with 15 vs 14 teeth sprockets on the 500 interceptor. Or just 15 for that matter. I'm very interested in your opinions about what is best and why you feel that way.
Also interested in the following questions:
Is changing to a smaller sprocket in front bad for the bike?
Will the 14t affect my speedometer/odometer?
Would you recommend putting the 15t back on?



Thanks in advance for taking the time to help me!

 

it will not effect you speedo, unlike newer bikes your speedo runs off the front tire. As for the sprocket that depends, are you 130 pounds or 230? do you live in the desert or mountains? There are a lot of variables in sprocket selection on any bike.

 

Regular Size

I'm 180 lbs. and live in NW Arkansas. Ozark mountains all around. Lots of curves, but I'll be commuting on the interstate some. What about the odometer? What effect will the smaller sprocket have?

 

Oh boy, the previous owner didn't do that one mod where they separate the mechanical mechanism responsible for speedometer vs odometer, did he? If so, you better stick with the stock 15 then... Sorry, I'm obnoxious. On a serious note, unless the rear suspension has been modified, I'd stay with the stock front and change the rear if you are not happy with the final drive gearing. A smaller than stock front sprocket will slightly change the bikes geometry and the way the swingarm was meant to behave. However, most riders would never notice. 14 will give the bike more "pep", less mpg, and chop the head off your top end. 15 will be a little slower off the line, give you better mpg, and give the bike a faster top speed potential. So, as you can see, you'll have to way the pro's and con's for yourself. Good luck, and welcome the the board.

 

I have to disagree with it changing suspension geometry since that is based off the pivot points of the suspension and to the best of knowledge the sprocket is in no way part of that mechanism. I would agree that changing the sprocket sizes will have a slight impact on the way the suspension reacts to throttle inputs due to the force being applied at a slightly different angle. The thing I have found about the little 500 is that the stock gear is about as good as your going to get for all around riding like you mentioned. I'm the same weight as you and run 14 tooth front BUT I also have a Magna trans in mine. 5th gear on the Magna trans carries the same ratio as 6th on the Ceptor and I can honestly say there is NO WAY I would ride the interstate in 5th (same as your 6th) with the 14 tooth. On the other hand the 1st gear ratio is identical on both trans and it is really nice to have the 14 on there leaving the line. even with a 15 tooth and the magna trans, which gives a top speed at red line in 6th of 155 v the all stock around 130, I'm uncomfortable with the rpm on the interstate. THIS site is helpful to let you know rpm at a given speed and compare sprockets.

 

A 15T countershaft sprocket with a 43T rear sprocket is the recommend combo for an unmodified VF500F. For reference the '84/'85 stock rear sprocket is 44T and the '86 is 43T. The stock countershaft sprocket is 15T for all years.

 

I will probably want to go on the interstate without having to worry about the rpm's being to high, but I've been riding around for the last couple days with the 14t, and really like the acceleration it has right now. I guess I'll just keep it this way for a couple weeks, then change to the 15 for a couple weeks and see which one I like better.

Thanks to everyone for their help. Even JTC for making fun of me. At least I learned that the speedometer and odometer run off the same mechanism. Anyone else with opinions about this topic, please keep it coming.

 

Wheelbase is affected.

 

yeah forgot you have to move the rear tire a couple of mm's