Anyone with 15/40?

[forceofnature]

Wondering if anyone is running the 15/40 gearing.  I was thinking of putting in a 15 with stock chain.

Kevin

[Professor]

Quite a few worry about chain issues with a 16 front. While I run a 16 (with a better than stock chain), I think a 15 would be really pushing it. A 15/40 would be right in between a 16/42 and 16/43. Both of these will still work with a stock chain. I have run both at the strip the 16/43 puts my 230# body through the lights in 4th about 10400rpm @137.5 mph

15/38 2.53
15/39 2.60
15/40 2.67
15/41 2.73
15/42 2.80
15/43 2.87
15/44 2.93
15/45 3.00
15/46 3.07
15/38 2.53
15/39 2.60
16/40 2.50
16/41 2.56
16/42 2.63
16/43 2.69
16/44 2.75
16/45 2.81
16/46 2.88
16/38 2.38
16/39 2.44
17/40 2.35
17/41 2.41
17/42 2.47
17/43 2.53
17/44 2.59
17/45 2.65
17/46 2.71
17/38 2.24
17/39 2.29
18/40 2.22
18/41 2.28
18/42 2.33
18/43 2.39
18/44 2.44
18/45 2.50
18/46 2.56

[forceofnature]

Ok so a stronger chain is recommended. Thanks.

[Professor]

Actually I'm recommending not going smaller than a 16 tooth countershaft sprocket at all. However that said, there must be some doing it as they are making them.

[BA BUSA]

Do not use a 15 front

[BusaCruise]

(BA BUSA @ Sep. 30 2006,03:00) Do not use a 15 front

but he'll like the clicking sound and how the chain will jump upand down after it kinks in about 10 places!

[badassblackbusa]

no 15 tooth bad bad things will happen. go 17-45

[Fat Busa Racing 1347]

I'v bin playing with my rear ratio and went from a 17/42

up to an 18/45 and picked up 3.5mph in the 1/4 after I

did this. The only thing I can put it down to was the

motor being able to put more torque thru to the rear by

turning a bigger front sprocket.

Just think how hard it is to to turn a small spaner on a

big nut ( me

) and put this to work in you thinking for

a rear ratio set up.......and hey presto

It worked for me. My time slips don't tell porky pies

[StreetnTrack]

We have sold a few 15 tooth sprockets to busa owners and haven't had a complaint yet.

[bigoltool]

My old bike came stock with a 15 tooth front. They have been around for years. However that was also a 630 (monster) chain. The switch to smaller chains also brought about the larger front sprockets to help them cope.

[The Big Red One]

(forceofnature @ Sep. 29 2006,06:31) Wondering if anyone is running the 15/40 gearing.  I was thinking of putting in a 15 with stock chain.

Kevin

I put a 16 front on an almost new stock chain and I have VERY little adjustment left. I won't wear this chain out before I have to shorten it

I doubt a 15 will even fit with the stock chain. Just change the rear sprocket...with a stand its actually pretty easy

[JohnnyBusa90]

Gen 1 Busa here. My Busa has 15F and 40R. What would that translate into in terms of top speed and acceleration? How would it affect my low, mid, and top end? I went to the drag strip yesterday doing 1/8ths and I felt like my times were slow compared to other Hayabusa's doing 1/8th miles.

[michael parris heuberger]

Gen 1 Busa here. My Busa has 15F and 40R. What would that translate into in terms of top speed and acceleration? How would it affect my low, mid, and top end? I went to the drag strip yesterday doing 1/8ths and I felt like my times were slow compared to other Hayabusa's doing 1/8th miles.

Hi. I do not know as I run 20F 34R with over drive 5th and 6th and a 200/55/ 17 tire. But it is turbo with NOS.

[JohnnyBusa90]

Yeah. Thats a no where near stock configuration . It doesn't sound street legal hahah. If I were to put numbers on it. 17F and 40R is stock configurations. Lets just say 1st gear top speed is 0 to 60 in 3 seconds and 0 to 100 (before redline) is 6 seconds on stock sprocket size. Since I have a 15F will my numbers look more like this 0 to 60 in 2.7 and since my top speed is lower I would only be able to go 0 to 90 before hitting redline? Would it be something like that? On 1/8th miles that would make my times slower right due to my top speed being lower but if the distance was say 1/12th miles I would have faster times compared to other busas because I wouldn't need the top speed to reach it?

[michael parris heuberger]

Yeah. Thats a no where near stock configuration . It doesn't sound street legal hahah. If I were to put numbers on it. 17F and 40R is stock configurations. Lets just say 1st gear top speed is 0 to 60 in 3 seconds and 0 to 100 (before redline) is 6 seconds on stock sprocket size. Since I have a 15F will my numbers look more like this 0 to 60 in 2.7 and since my top speed is lower I would only be able to go 0 to 90 before hitting redline? Would it be something like that? On 1/8th miles that would make my times slower right due to my top speed being lower but if the distance was say 1/12th miles I would have faster times compared to other busas because I wouldn't need the top speed to reach it?

,Hi. It is a LSR/ street bike when it is done it will race at Loring Main i hope it will run in the 280+ MPH It will run different gearing on the street. For evwry day street I have a supercharged busa.