49 Tooth guys

Gohot229

Gohot229

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I'm wondering if many of you have run a larger rear sprocket and if so what was the increase of teeth? As for front sprockets ....as I gather the FZ1 will not take a larger one up front because of case clearance. As for reducing the front sprocket a tooth, I'm not for that, and I'll tell you why. As the chain races forward curves down and around then races rearward, the apex of dirrection reversal is the sprocket as we all know. Now if you reduce the radius of the dirrection change you increase the speed which it passes and thus incease load and shear factor. I don't know if I'm making this clear enough, but the old timers will know what I'm talking about, and I think you newer bike people will remember this in discussion somewhere or other previously. So for me, two things become aparent, and going against current thinking a reduction in front would provide two things, 1 a greater clearance of the cases, not really needed however, and 2nd a gear ratio reduction/increase, depending upon your point of view, a reduction in front teeth=an increase in rear (effective) teeth, without actually touching the rear sprocket. Anyway, through these rambelings, how many of you have used a larger rear, and did you stay with it or revert back to the 44 tooth stock? For those who did, how was the 'seat of the pants' feel? and how was the tach doing at say 60mph. Did it become a roll-on weelie bike with effortless lofts?, Was it winding too high in street highway traffic to feel good about? Did you like it?....... or not like it?
 
I run 15/47 ... I'd never go back to stock...

let me go ahead an dispel a few myths for you as well....
I went to 520. No decrease in chain life.
I dropped a tooth up front. No decrease in chain life.
First, I used a aluminum rear sprocket .... I'll never do that again... it lasted 6k miles
Most people adjust their chain wrong. If you go out to the garage before a ride, put the bike on it's centerstand and adjust the chain... you're doing it wrong. The chain should be adjusted when hot. The chain shrinks when hot, so if you adjust it when cold, it gets too short, therefore too tight when hot. This will make your sprockets and chain wear out faster.
 
15/47 as well with a speedohealer for correction -- was around 13% off for correction factor.....speed verified with GPS vs speedometer.
 
Aaron, my understanding of thermal dynamics is that metals expand when hot and shrink when cold. If you adjust the chain cold and then ride till hot, it will be too loose, correct? If you adjust hot and let it cool, it will shink and become tight?

Please explain if I am wrong. ;)
 
FZ1inNH said:
Aaron, my understanding of thermal dynamics is that metals expand when hot and shrink when cold. If you adjust the chain cold and then ride till hot, it will be too loose, correct? If you adjust hot and let it cool, it will shink and become tight?

Please explain if I am wrong. ;)
Click to expand...

you're completely right... but in this case, what is happening is that the pins heat up and expand... drawing the links closer together, thereby shortening the chain.... so... adjust cold, ride till hot, the pins expand, draw the links closer together and the chain is too short.
 
va_rider said:
you're completely right... but in this case, what is happening is that the pins heat up and expand... drawing the links closer together, thereby shortening the chain.... so... adjust cold, ride till hot, the pins expand, draw the links closer together and the chain is too short.
Click to expand...

Ahh! Thanks! Now I get it. :D That makes sense and I hadn't thought about it. Going to get MORE coffee.....
 
I run 17/48, and am considering 17/49 on next change out. Bike responds excellent and shortens wheelbase just short of one inch. Helps in the twisties, which is all this bike does.

Also chain snatch goes way DOWN with the 48. 530 with hardened alum rear.
 
va_rider said:
you're completely right... but in this case, what is happening is that the pins heat up and expand... drawing the links closer together, thereby shortening the chain.... so... adjust cold, ride till hot, the pins expand, draw the links closer together and the chain is too short.
Click to expand...

Not only did I find evidence backing this, but exact measurements.

"The typical motorcycle chain has 112 to 116 links. When measuring tension, the difference between a warm and cold chain will be 1/4" (based on a 530 chain). If you are adjusting a cold chain, please allow the extra 1/4" of slack to compensate for the shorter warm chain."

This is from a book my boss has. I checked and the FZ1 has 114 links on the OEM 530 chain.
 
I've got a Gen 1 bike. Just to see if I liked it I tried a 15 tooth vs the stock 16 up front. It helped the bike in every way. I was told that it will add about 10mph to the top end because the bike won't pull 6th all the way out with stock gearing, 16/44. The person that told me this has had plenty of experience topping out FZs for years.
After trying this I installed a new OEM 16 up front and a Sunstar 47 in the rear. 1 down in the front is the same as 3 up on the back. Of course going 3 up on the back requires me to buy a new chain. Stock is 116 links. 119 links should cover it with the 47 tooth rear. I'm waiting for the chain now. 119 links is based on what others have said. Go 1 link for each added tooth on the rear.
I'm kind of old school on dropping the front sprocket vs going up on the rear. Even though the wear factor is hardly any different by going smaller on the front, it still has to be more so vs going up on the rear. You just have fewer teeth engaged in the chain. It also puts more chain pressure on the sliders on the top and bottom of the swing arm.
It will always be more popular to drop a tooth up front because you can use the stock chain. For me, I'll go 3 up on the back, and then if I want to set it up for the drag strip I could put the 15 tooth front sprocket back on it along with the 47 rear. From what I've read on this forum, that combo will really eat rear tires and save your front!
 
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Flexwing man said:
I've got a Gen 1 bike. Just to see if I liked it I tried a 15 tooth vs the stock 16 up front. It helped the bike in every way. I was told that it will add about 10mph to the top end because the bike won't pull 6th all the way out with stock gearing, 16/44. The person that told me this has had plenty of experience topping out FZs for years.
After trying this I installed a new OEM 16 up front and a Sunstar 47 in the rear. 1 down in the front is the same as 3 up on the back. Of course going 3 up on the back requires me to buy a new chain. Stock is 116 links. 119 links should cover it with the 47 tooth rear. I'm waiting for the chain now. 119 links is based on what others have said. Go 1 link for each added tooth on the rear.
I'm kind of old school on dropping the front sprocket vs going up on the rear. Even though the wear factor is hardly any different by going smaller on the front, it still has to be more so vs going up on the rear. You just have fewer teeth engaged in the chain. It also puts more chain pressure on the sliders on the top and bottom of the swing arm.
It will always be more popular to drop a tooth up front because you can use the stock chain. For me, I'll go 3 up on the back, and then if I want to set it up for the drag strip I could put the 15 tooth front sprocket back on it along with the 47 rear. From what I've read on this forum, that combo will really eat rear tires and save your front!
Click to expand...

Great post, thanks! I've been thinking to pick up a 15 tooth for up front. It's an easy enough swap in case your not happy with the results and the money expended is not that big a loss. I think it's less than 25 bucks. How did you like the pick-up with the 15t and also did you do any roll-on tests with it installed?, not that the FZ has any issues with roll-on to begin with.
 
Yes, I did a lot of roll on tests with two other FZs. Both of these guys work at the same company as I do and we've done a lot of riding together. One bike is an 09 FZ1 with full yosh pipe. At the time he had only put the pipe on it and hadn't done a remap. The 09 would always stay ahead of me until I did the gear change. After that he could not. I'd slowly pull ahead in all cases. We did roll on tests in evey gear from 20 mph to 80 mph. The 2nd Gen stock bikes are are normally slow from 60mph 6th gear roll ons. Their 5th and 6th gear ratios have been changed from the 1st gen bikes. The other bike that I tested with was an 03 FZ1. It was set up with a slip on and rejetted. Before the gear change the two of us were very close to even. He may have had a slight edge in 6th because of weight and the bike had more miles on it vs mine. I weigh 200lbs and my bike had around 4000 miles at the time.
Again, after I dropped the front 1 tooth my bike excellerated better than both of them. It wasn't a huge difference, but it did make mine quicker than both of the other bikes.
My bike has Dale Walkers slip on, ais kit, stage 1 jet kit, airbox mod, and 3 degree advance plate. It couldn't run any better engine wise with the basic mods I've done to it.
 
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OK, what change in sprockets will allow me to stay close to the stock speedometer reading? I know when I went more teeth on the rear on my FZ6 the speedometer was very generous. I know I could buy a speedohealer, but I don't wanna!
 
well... from the factory, the Speedo runs about 3-5% high depending on the tire you're running... so... to take you closer to being correct, you actually have to drop a tooth off the rear.. which.. is no fun...
 
va_rider said:
well... from the factory, the Speedo runs about 3-5% high depending on the tire you're running... so... to take you closer to being correct, you actually have to drop a tooth off the rear.. which.. is no fun...
Click to expand...

You know that is not the answer that I wanted :cuss:

I guess I will just have to go with a 47 on the back and figure out what the delta is.
 
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