From what I understand from this forum, dropping a tooth on the front sprocket should help gain low end for drag racing so gaining teeth on the rear would do the same. I hope my question will make sense. Are there differences in how these gear changes affect the low end as in e.t. vs mph? Let me try to explain a little more. My goal is to increase low end for drag racing. But I didn't know if gaining teeth on the rear sprocket would show up more in mph or e.t. Or if dropping a tooth on the front would show up in mph or e.t. Or will these sprocket changes show the same kind of effect. I hope this makes sense to someone.
Sprocket question for Gen II
- Thread starter pbpd4816
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Ludicrous Speed
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One tooth in the front equals about three in the rear. You can go too far, but I was 17/46 on my Gen 1 bike. I am a heavy guy though, and it was easier to launch that way. My friends that are lighter usually only go about three teeth in the rear.
I like to change the rear, as going smaller on the front decreases the chain wrap and can be harder on the chain.
I like to change the rear, as going smaller on the front decreases the chain wrap and can be harder on the chain.
You will acelerate quicker, but each gear will run out quicker also with either, and each gear's top speed will be less. Adding teeth to the rear and subtracting from the front will each have a noticeably different feel too. Going down in the front will feel like less torque and faster revving, where as adding to the rear will feel like more torque. For example the old -1 front = +3 rear is a common misconception. Although the final gear ratios are very similiar on paper, just -1 does not feel the same as just +3.
-1 and +2 or 3 rear are popular combined for drag racing, because adding to the rear alone will as said give you the feel of noticeably more torque. Thus the bike is much more wheelie happy, and that much harder to keep the front down. Less teeth on the front sprocket allows the engine to use it's available torque less effectively(makes it a little easier to keep the front down). So combined, you can accelerate faster easier with less revolutions of the front sprocket, and more of the rear with the engine working the same. The trade off is that you cannot tach the engine any higher so you must shift sooner, which isn't a big deal in the 1/4 mile.
Make sense?
-1 and +2 or 3 rear are popular combined for drag racing, because adding to the rear alone will as said give you the feel of noticeably more torque. Thus the bike is much more wheelie happy, and that much harder to keep the front down. Less teeth on the front sprocket allows the engine to use it's available torque less effectively(makes it a little easier to keep the front down). So combined, you can accelerate faster easier with less revolutions of the front sprocket, and more of the rear with the engine working the same. The trade off is that you cannot tach the engine any higher so you must shift sooner, which isn't a big deal in the 1/4 mile.
Make sense?
Ludicrous Speed
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I would not go that low to start with. DO you street ride? Interstate or freeway? You will notice a big difference at highway speeds. Do one or the other at first.
Yes, I'm 175, 195 with leathers. I had my gen2 just +3, just -1, and -1 +3. I prefer just +3, but I don't drag race, aside from the ocasional rip against friends. I've also run countless gearing combos on many sport and dirtbikes over the years.
-1 +2 or 3 will get you off the line and down the track quicker, as well as making it easier for you to keep the front down.
Consider an airshifter and setting your factory shift light too.
I would first try +3 on the rear 18/46...it works with the stock length chain. If that's not enough, then you can drop one on the front...17/46...that would be plenty.
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Both or either fit the stock chain too, with plenty of slack for adjustment. I'de have to disagree with just +3 rear on a gen2 for drag racing though(I love it that way though). It's going to make keeping the front down alot harder than with the -1 front too.
Been there, done that.
I just installed a CO2 air shifter from cycle tek. Do ya'll have preferences as far as brands for sprockets? Steel or aluminum? I know steel will last longer but is the lighter weight of aluminum make it worth going with? I want a black in color rear sprocket. I've looked at all the brands offered but don't know which brand is a better choice in general or for drag racing specifically.
Ludicrous Speed
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I prefer steel, but I am not concerned with that hundreth of a second.
JT or Sunstar is what I always run
JT or Sunstar is what I always run
jefro
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Had one on for over 2 years now and love it! Much crisper shifting. Makes neutral a little harder to find at a stop sometimes, but not bad at all. Along with the Sato rearsets it shifts like a completely different bike.
r1d3on3
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17/45 is a pretty good combination and would prob suit your weight. If I was you I would try just one down in the front to start with because if you've just been running around stock gearing on the street your going to notice a huge difference. I weigh 145 and 17/45 is what I went back to running last weekend in the 8th. I'm pretty green though at the drags with one season and first bike/vehicle ever on the drag strip. I've done 17/43, 17/45, and 16/45. 16/45 is wayyyy too much for my setup and body weight, plus the 16 th is gonna naturally be harder on the chain. Something to consider too i guess and maybe it doesnt make a huge difference, is dropping a tooth in the front lengthens the wheel base and going up teeth in the rear reels it back in for a shorter wheel base. I'm trying to work on wot by the 60' and i might find 17/45 is too much when i get close to my goal, but it felt pretty good last weekend. Small changes at a time is the way to go. Also front sprocket if i remember- 25 bucks or so, back sprocket 75+
I have a gen 2 busa with +3 on the rear and love it. It shortened the wheel base too, which helps the busa corner carve better. Moved the rear wheel almost a half inch forward. I am 175lbs at 5'8" and probably around 190lbs with gear.
Ok so... Some clearing up with the whole gear thing. -1 front is close to +3 on the rear. The front is a gross adjustment. The rear is a fine adjustment.
Also when you go down in front, the rear wheel moves away from the front wheel. Better to help keep the bike from coming up, due to a longer wheel base. If you add a tooth to the front sprocket, the wheel base gets shorter.
If you add teeth to the rear, the wheel base gets shorter. If you subtract teeth from the rear, the wheel base gets longer.
Smaller the front sprocket, the harder it is on the chain. Because it has a smaller base circle to go around... More energy is consumed due to fact the chain has to turn more on the sprocket compared to a larger sprocket.
So you need to watch what you do when you select a certian type of gearing.
Ok so... Some clearing up with the whole gear thing. -1 front is close to +3 on the rear. The front is a gross adjustment. The rear is a fine adjustment.
Also when you go down in front, the rear wheel moves away from the front wheel. Better to help keep the bike from coming up, due to a longer wheel base. If you add a tooth to the front sprocket, the wheel base gets shorter.
If you add teeth to the rear, the wheel base gets shorter. If you subtract teeth from the rear, the wheel base gets longer.
Smaller the front sprocket, the harder it is on the chain. Because it has a smaller base circle to go around... More energy is consumed due to fact the chain has to turn more on the sprocket compared to a larger sprocket.
So you need to watch what you do when you select a certian type of gearing.
So if you like a little more grunt and better low speed manors on the gen2. The -1 front or the +3 rear are pretty good combos. If you want better wheelie control and stability, go to the -1 front sprocket. If you like wheelies and a better turning busa go with the +3 rear sprocket. I hope this break down helps!
Had the same problem I found that if I fed the clutch out just a little it would find neutral as easy as stock
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