Front Sprocket

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FSTZ1

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I'm thinking about changing the front sprocket on my '03 FZ1. I'm not too interested in doing wheelies or drag strip launches, but actually slowing down the 'launch' so I can get a bit more out of first gear before having to shift into second. Has anyone replaced their front sprocket, and would that require adding a tooth over the existing number of teeth on the stock sprocket?
 
Dropping DOWN a tooth on the front sprocket will probably give what you are looking for. It will make it easier to take off without first gear being too "tall". In the city it makes for a lot easier riding. Common wisdom is to go to the 16 tooth front sprocket. Nice change for $35?
 
ok... as per your original post... you're looking for "taller" gearing.. so you want more out of 1st before having to shift... in effect, raising your "possible" top speed and lowering your RPM.... for instance, at cruising speed, say 70MPH, instead of 4500RPM, you'll be at 3700RPM ... if this is the case, than your original post is correct... you would theoretically go UP a tooth on the front... however, since you have a Gen 1 ... the stock sprocket is a 16 Tooth... a 17 will not fit up front without doing some grinding to the case... so... the next option would be to drop to about a 42 in the rear instead of the stock 44.... stay with steel. Aluminum IMHO is crap. I had a Vortex rear sprocket, in 6,000 miles, it was done.... completely... the chain was kept in proper adjustment the whole time, and the drivetrain was aligned using a laser alignment system... the sprocket just couldn't handle the bike...


All of this said, I think going up a tooth on the front, or dropping a few on the rear would be a bad idea.... I know where I live, with stock gearing, I would have to slip the clutch just to make it up a hill... Your cruising RPM will be lower, but I don't think you'll ever use 6th gear again....
 
If your goal is to reduce your cruising RPM and make first gear last a little longer reducing the rear sprocket by a couple teeth will probably work. If you are lighter like me (150 Lbs.) you won't have any problem with launching the bike but if you're a heavier rider (200-250) you might not like the taller gearing. That's just part of the price you pay for changing the overall gearing. At least it's pretty easy to reverse if you decide you don't like it.
 
why not go down one tooth in the rear ? you want a little taller first gear but dont want to slip the clutch to take off , going down one not really a big change but your rpms will show it
 
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with him wanting first gear to run out further he has two options up in front ( in order to do that he has to grind on his case to make room)or down in the rear .sounds to me he does not want launches or fast take offs and if he goes down two in the rear it would be hard to take off so a happy medium for him is one down in the rear
 
hope I'm correct in my own understanding, here goes...

Say you have a 16/44 sprocket combination (stock), that combination yields a ratio of 2.75. Meaning that the engine turns 2.75 revolutions per one complete turn of the rear wheel. If you were to change the rear sprocket to a smaller rear, 16/42 or -2 in the rear, one would have a ratio of 2.625. This would have the effect of lowering the engine revolutions to make one complete turn of the rear wheel and would lower the overall RPM of the engine at a given speed (effects would be slower takeoffs at the line, possible increase in fuel efficiency, and possibility of having a higher max speed)

Say you wanted a 16/46 or +2 in the rear, the ratio would be 2.875. This would have the opposite effect b/c one would be increasing the engine RPM at a lower speed to harness the power that would be available (faster takeoffs, possible decrease in fuel efficiency, and lowering the overall max speed)

With the second scenario, you are using the available power of the engine faster b/c of the higher RPM's.

Myself, I'm running a 15/47 or -1/+3 combination which yields a ratio of 3.13. Higher engine speeds to reach the power band faster, decreased fuel economy (especially in my case) and lower max speed (but I haven't gone over 110mph yet and I still have room to go....)

Have you verified what you have for a sprocket combination? The original owner may of changed and you might be able to drop back to a stock configuration and achieve your desired reslut.

Hopefully the above helps (and hopefully my explanation makes sense and is correct...I feel like I just turned in a test and the professor is about to give me a grade :scared:)

BroHay
 
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Good job Brohay... except for raising the top speed... yeah, that's true, IN THEORY..... but in reality, it'll lower the top speed because the bike won't be able to overcome the wind drag.... when I went from stock gearing to 15/47 I actually gained a few MPH up top... because I could do a better job of overcoming drag... ask your regular un-modded Gen 1 owner... they won't be able to hit redline in 6th...
 
Gear ratios

I want to thank everyone for their input and comments. I have the stock sprockets on my bike. It is an '03, and I just bought it last year, new from my dealer. I weigh about 180 lb, and it just seems that first gear winds out pretty quick. I think I will experiment with first going down a tooth on the rear and see what effect that has on the overall gearing.
 
it's normally a better idea to go up in the rear, than down in the front... basically, is you put a smaller sprocket up front, the circumference of the chain around that spot gets tighter, increasing chain wear... so... I believe the stock gearing on a gen II is 17/44 a lot of Gen II guys go to a 15 and keep the stock rear..... If you're just looking for a bit more takeoff, I'd try a 15 up front, and leave the rear as is.... if you're looking for much faster acceleration, and perhaps some hooligan type antics.... well, that's the time to go with the 15/47 gearing..
 
I am thinking about changing my front sprockett

I live in the mountains of East Tennessee and I love it here but I feel my bike is a little hard to get going out of the hole I am going to change the front sprockett to a 16 tooth. My bike is pretty stock I have only replaced the stock muffler with a yoshi slip on and removed the ugly rear fender. Oh and by the way it's 69 miles from my front door to the deals gap store. Yeah it's a rough life. But somebody's gotta do it. No if your riding this way hollar and I can show you some more pretty good roads to ride ones not on the beaten path. I hate traffic and cops. < hasn't had a ticket in 17 years but loves to go fast! I'm on you tube.
 
Wich year do you have and what else did you do when you put the pipe on? Maybe you could use some fuel mixture help. I know it's a bit hilly where you are but I know my bike wouldn't have any problems off the line unless I was in full race mode.
 
-1 front sprocket

Yes, I'm highjacking.

Ditto on the -1 front sprocket. It has made a HUGE difference for me in town. No more lugging or feathering the clutch getting across the cross-walk. The bike has much better acceleration. Before the change I could hit 90mph in first gear at redline (my speedo) now "only 82mph." As far as freeway cruising it revs about 300 rpm more depending on speed. IMHO, it is well worth the $9 I spent on the Sunstar sprocket on Ebay.
 
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