Suzuki GSX650F Forum - www.GSX650F.biz

Want to change my front sproket to a 16 tooth, if you have done this where did you get your parts?

The sprocket is a "SUNSTAR" part# 40416. Purchased thru my Suzuki dealer, cost is $18.00 plus tax. That same sprocket fits several model Suzuki and Kawasaki motorcycles.

If you do a search there are a couple of threads with instructions. Main thing, the nut is 32mm, use thread locker when you re install the nut that holds the sprocket.

Suzuki would do well to offer this as the factory standard sprocket as it improves the riding greatly for most folks.

Frankc

I used a JT Sprockets part number JTF520.16 purchased from www.motorcycleproshop.com. Also, a 1 1/4 inch socket will work if you don't have a 32mm socket.

Frankc is right, a 16 tooth front sprocket should be standard on the GSX650F. It not only improves the riding experience, it also corrects the speedometer error.

When you say improves riding experience ,how do you mean?

I find that it just "rides" better. There is less vibration in the handle bars at highway speeds. I went on at 60 mile trip the other day and my right thumb didnt go numb. And it usually would after just 20 or 30 miles on the highway. At 70mph the tach is at 5800 Rpm instead of 6200 Rpm.

...yeahhhhh, but with less acceleration, right? I already find myself using WOT in any gear other than first. Not being negative about the sprocket swap, this is just the issue that has prevented me from doing it myself.

Did you guys replace your chain at the same time as the sprocket or did you find this to be unnecessary ?

I honestly have not noticed an acceleration difference going from a 15 to a 16 tooth front sprocket. However, that's just my subjective impression since I don't go to the drag strip for timed runs. I would be interested in seeing that information if anyone has done a before and after timed drag race.

There's more than enough adjustment range using the stock chain to use a 17 tooth front sprocket if you wanted.

If acceleration is a problem, just kick it down a gear and roll on the throttle. Problem solved!

I've heard of the "speedo error" on the 650F, and a few guys have said sprocket changes fix the speedo error?
How does it do that? I thought the speedo cable is hooked to the front tire, and it simply measures tire rotation/revolution speeds, and then you get a reading on the digital readout. I am not sure what is correct. Can you guys clarify this so I know my true speed? Is there a different way to calibrate it if it's off?

I found this thing called "speedo healer" but it seems very expensive ($107 USD)
Does it really work?

http://www.baysideperformance.com/index ... c74c9ecb1c

oops, my bad. I am an ignoramus once again. After looking at my bike, I understand now that the speedo sensing is electronic, not the old gear driven front wheel deal. Anyway, where is the sensor? Does it pick up something in the trans or what is it sensing?
I wonder why there is this 10% error thing, seems like in the modern era the electronics engineers could make the thing sense speed accurately, don't you think.

Here is the link for the one I bought. http://www.motorcycleproshop.com/detail ... =JTF520-16

The easiest and cheapest way to correct the speedometer error is to fit a 16T front sprocket. The speed sensor is under left side cover that you have to remove to replace the sprocket.

The speedometer error correction is an "automatic" result of changing the size of the sprocket. There is no other adjustment needed to correct the speedometer error if you simply install a 16T front sprocket.

I did notice a little less acceleration after the changing the sprocket, but not enough to disappoint. The bike has plenty of power and can still blow away any youngster in a sports car! Besides, I like that fact that 1st and 2nd gears are much more usable. I don't have to be in such a hurry to up-shift now. And, as others have pointed out, there is less vibration, fewer RPMs at speed, and no speedometer error. The best bang for the buck upgrade available!

Ok , now I understand it.

But, You would think Suzuki would have the thing dialed in to accurate speedo readout from the factory, and if you changed sprockets it would be off. Instead it's kind of backwards to me, meaning when you change it over to a 16 tooth, you finally get the speedo accurate.
Oh well, such is life!!

But the odometer will be off with a 16 tooth. Budget bike, budget solutions.

ok guys, one last question beating this horse to death.

With my stock 15 tooth front, say I'm going 50 mph on the speedo, am I really going 10% slower, 45 mph?
And then , say I have a 16 tooth, is the odometer reading less miles or to the plus side??

I won't ask anymore once this is clear to me!! I promise.........