guys back me up here pleaaaase! sprocket controvesy

shogun

shogun

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ok, im having this debate with my freind, he says that a 17/40 gearing setup will do quarter mile faster than a 17/43 setup. he also claims that that bike A with the 17/40 setup will beat bike B with a 17/43 set-up in a quarter mile race.

DOESNT THE BIKE WITH THE BIGGER REAR SPROCKET GET TO 60MPH FASTER THAN THE BIKE WITH THE SMALLER REAR SPROCKET?:whistle::thumbsup::beerchug:
 
Assuming the 17/43 doesn't redline in 6th gear before the end of the 1/4 mile (it won't on a Busa), the 17/43 will win all else being equal.
 
yes and no... rider, motor, tuning, tires but more rider than anything.. if bigger was always better guys would have 100 tooth rears..

I would say rider has more to do with this than sprocket size..
 
true. im just saying two of the EXACT busas, the one with the 17/43 setup would beat the one with the 17/40 setup in a 1/4 mile..right. lets say both riders are the identicl skill level. the point is that the 43t in the rear gets you to lets say 100km/s faster than the 40t rear will. right.
 
correct :beerchug: more teeth in the rear means faster acceleration and lower top end if everything else is equal
 
ok thank you. my freind just made another claim he jsut woint give up lol. He says that you have to twist the throttle more on a bike with a 43t where as a bike with 40t you have to twist the throttle less to get to the same speed. is this correct?:laugh:
 
Yeah this is the same old argument.

"size doesn't matter" I've said that all my life and I am sticking to it!

:laugh:
 
My understanding is that the output of the crank is translated to greater acceleration via the 17/43 setup but sacrifices top speed, while the crank output to the 17/40 setup provides greater top speed at the expense of rate of acceleration.

That means that the 17/43 setup would require more throttle to match any given speed as compared to a 17/40 setup, while the 17/40 setup would require more throttle to match the accelartion of a 17/43 setup.

The real question how well does a given rider use one setup or the other in the 1/4 mile contest. If you're able to max out in top gear before the finish line in terms of acceleration, then you'd want adjust your sprockets for a greater top speed. Idealy you want to be able to accelerate fast enough to reach top speed just before you cross the trap.
 
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melodic, great answer man. just to be clear, me and another busa riding perfectly side by side, same gear. busa 1 has a 17/40 and busa 2 has a 17/43 setup, we both decide to open up the throttle at the EXACT same time for 3 seconds, who ends up ahead of the other in 3 seconds? busa 1 or busa 2?:beerchug:
 
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shogun said:
melodic, great answer man. just to be clear, me and another busa riding perfectly side by side, same gear. busa 1 has a 17/40 and busa 2 has a 17/43 setup, we both decide to open up the throttle at the EXACT same time for 3 seconds, who ends up ahead of the other in 3 seconds? busa 1 or busa 2?:beerchug:
Click to expand...

Assuming all else is equal (rider weight, skill, tire condition/grip/hook, etc.), the 17/43 setup should achieve greater speed SOONER (which, in your example would mean that busa 2 has traveled farther in the 3 second period).

The trade off is that if the race continues long enough for each bike to reach top speed, the 17/40 would reach a higher top speed but not until AFTER the 17/43 had already reached it's LOWER top speed.

Bottom line, in a 1/4 mile, the 17/43 wins. In any race long enough for the 17/40 to take advantage of the higher top speed for a enough time, the 17/40 wins as it will catch up to and pass the 17/43 that has the greater acceleration.
 
Gearing is an age old debate... it is optimized to any given motor and/or tuneup..

for instance..
A car with 500hp via a 327cid motor vs a 500hp 427cid motor..

the larger displacement motor needs to utilize the torque curve much more than the small motor.. the small motor must use the high RPM part of the curve and so a taller gear (ratio) is required

IE> 5:13 gear vs a 4:11 for the big motor.. they both cross the line at the same speed however based on HP.. the difference will be in ET due to weight now..

MPH in the traps is almost purely a function of HP and not gearing so much.. BUT the motor must be geared optimally for the 1/4 mile.. ET is HP/weight/gearing.. point being if you got a fatazz 300lb rider on the busa, it is going to require a taller sprocket in most cases when a lighter rider will do just fine on the OE gearing..

change pipes, cams, tires or any other part of the tuneup and all bets are off.. time to try gearing going in both directions again..

Fun thing about drag racing... the combinations are almost unlimited and so never a real "fixed answer"
 
I think y'all are reading way too much into the question.

Run your Busa down the 1/4 mile with 17/40. Before the next pass, swap out the rear sproket for a 43. Your next pass down the 1/4 mile will be faster (assuming you are a consistent racer).

Yes, it takes more throttle to maintain the same speed with a 43 vs a 40 rear, but that doesn't have anything to do with 1/4 mile times.
 
u think i'll notice a diff in how much throttle it takes to maintain speed with my 43 vs my 40?
 
shogun said:
melodic, great answer man. just to be clear, me and another busa riding perfectly side by side, same gear. busa 1 has a 17/40 and busa 2 has a 17/43 setup, we both decide to open up the throttle at the EXACT same time for 3 seconds, who ends up ahead of the other in 3 seconds? busa 1 or busa 2?:beerchug:
Click to expand...
busa 2
 
shogun said:
u think i'll notice a diff in how much throttle it takes to maintain speed with my 43 vs my 40?
Click to expand...

youll notice a dif. in torque feel but not likely gonna notice your maintaining at 40% throttle position instead of 30%
 
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