rear sprocket question

john32303

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hi all

was thinking about ddropping a few teeth on the rear sprocket on one of my bikes. might go as drastic as 5 to 7 teeth. i usually never ride the bike under 75 or 80 and mostly highway miles. I am thinking that with the smaller rear sprocket, that i will get better gas mileage. will there be any other effects of a smaller sprocket?

thanks
john

Aquaman

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You wont have seat of the pants power when you give it hard throttle. Get a speedo healer if you do.

BA BUSA

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hi all

was thinking about ddropping a few teeth on the rear sprocket on one of my bikes.  might go as drastic as 5 to 7 teeth.  i usually never ride the bike under 75 or 80 and mostly highway miles.  I am thinking that with the smaller rear sprocket, that i will get better gas mileage.  will there be any other effects of a smaller sprocket?

thanks
john
I think that a 38 is the smallest that they make for the rear. If you go down 5-7 on the rear, you will have to shorten your chain. If you run a 18 front and a 38 rear...it will be the same as going down 4 1/2-5 on the rear...plus you can run the stock length chain.

Going to a set up like this will hurt acceleration big time, but it will cut your crusing RPM's and help gas mileage some.

DREW

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I am currently running 17/39. Not much different from stock. Will be going back to 17/42.

BATTMAN

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If you are going to drop that many teeth on the rear, you might as well trade your busa in for a 600.

busa666_1977

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want to gain a bit more accelaration on my 2008 busa was thinking of changing the rear sprocket up two to three teeth can any one tell me if this will help and does it cause any probs with speedo. cheers chris

rubber2burn

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want to gain a bit more accelaration on my 2008 busa was thinking of changing the rear sprocket up two to three teeth can any one tell me if this will help and does it cause any probs with speedo. cheers chris


Going up in Teeth in the rear will give you more acceleration and yes you will need to get a speedo healer to take out the inaccuracy in the speedo :welcome:

boosta1395

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Any changes on the sprockets will mess with the speedo. On the older bikes where the speed sensor was on the front wheel it didn't matter.

Mr Bogus

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Any changes on the sprockets will mess with the speedo. On the older bikes where the speed sensor was on the front wheel it didn't matter.
What years had the speedo sensor in the front wheel? I had no idea the Busa ever had a front wheel speed sensor..

BusaWhipped

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Swap out to an 18 tooth front and see if you like that. From there you can decide whether or not to drop teeth in the rear. 18/40 is a nice cruising combo.

busa666_1977

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i have a 2008 busa, 18/42 sprockets, i wanted a bit more acceleration so was going to go up 2 teeth on back but am not able to get a 44tooth sprocket in stealth in the uk so have managed to get a 43 will droping a tooth on the front give me the same result. please could someone help.

jefro

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Take another look at your rear sprocket. My '08 came with a 43T rear.

Commuta_Busa

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Once you're up to your cruising speed of 70 or so I can see that have the engine run at lower revs by swapping sprockets would be a positive in mpg. The only thing is that during acceleration you may end up turning the throttle more than you prviously did to accelerate which would decrease the mpg. If yo've got very long boring highways miles to run say 50+ miles at a clip then changing the sprockets may increase your mpg but if your commute isn't that long then you may not see much of an advantage.
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