42t rear?

ZeePopo

Registered
So I ordered a supersprox chain sprocket combo and instead of a 43 rear I got a 42. Keep it or send it back?
 
The 42t will make the bike more sluggish feeling at lower rpms.
The trade off is a higher capable top speed; however you would need the ecu restriction removed, and perfect conditions to see a potential top speed approaching 200mph.
Your highway cruising rpms would drop around 200 rpms.
The wheelbase will be slightly longer.
The bike will need more effort to lift the front tire.
Maybe, maybe you get another mpg or so out of the bike.
Not a lot of practicle application.

A 46t rear will shorten the wheelbase slightly. Upper limit cornering capabilities will improve a little from this.
It will take away top speed, but you should still easily be able to go low to mid 170s(mph).
The front tire will lift with ease, especially 1st and 2nd.
The bike will accelerate quicker, and the midrange will feel much stronger.
Lower et's at the dragstrip are possible.

It all comes down to your riding style.
If you just like to cruise or commute, the 42t is fine.
If you like an aggressive feeling bike to play on, then the 46t is a noticeable improvement.
 
The 42t will make the bike more sluggish feeling at lower rpms.
The trade off is a higher capable top speed; however you would need the ecu restriction removed, and perfect conditions to see a potential top speed approaching 200mph.
Your highway cruising rpms would drop around 200 rpms.
The wheelbase will be slightly longer.
The bike will need more effort to lift the front tire.
Maybe, maybe you get another mpg or so out of the bike.
Not a lot of practicle application.

A 46t rear will shorten the wheelbase slightly. Upper limit cornering capabilities will improve a little from this.
It will take away top speed, but you should still easily be able to go low to mid 170s(mph).
The front tire will lift with ease, especially 1st and 2nd.
The bike will accelerate quicker, and the midrange will feel much stronger.
Lower et's at the dragstrip are possible.

It all comes down to your riding style.
If you just like to cruise or commute, the 42t is fine.
If you like an aggressive feeling bike to play on, then the 46t is a noticeable improvement.
Either work with the stock length chain.
 
I have the 42T SuperSprox on the '08. I honestly can't tell the difference with acceleration though.

My goal was better gas mileage for Iron Butt Riding actually.

Made 250 miles on one tank of gas so couldn't be more happy with the choice.

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I put a 39 tooth rear sprocket on my 08 and can feel a very, very minimal difference in the low end. Although, the high end is much stronger and the MPG's are 50-52 during normal interstate commute riding. Your choice, but I think you know which way I am leaning.
 
I thought about getting one but why pay the extra $$ when I will replace it everytime I do the chain.
 
So are you guys really seeing that much improvement in mpgs? How fast are you going or what is your rpms? I drive 8 miles to work and that's not much so maybe ill leave mine stock.
 
So are you guys really seeing that much improvement in mpgs? How fast are you going or what is your rpms? I drive 8 miles to work and that's not much so maybe ill leave mine stock.

I saw a huge increase in mileage during my 120 mile round trip commute. Although, I am 100% sure the 39 tooth sprocket is not the only thing to credit. I also installed the CCS-100 cruise control which maintains my speed almost to the exact point I set it. I usually cruise between 70 and 75 based on the flow of traffic and am right around 3750 RPM.

After calibrating my speedometer with a SpeedoDRD, I consistently get 50 MPG during my commute.
 
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