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Discussion Starter · #1 ·
well i dont own a 250r. might get one just for the heck of it. but i was wondering what sprocket upgrades have people done? ive done some looking and found that a lot of riders of the 250 do a -1 in the front. but wouldnt the -1 in the front give you better low speed? the 250 i feel needs a little more end. i do highway cruising and want the rpms to drop. so doing a +x front and -x in the rear would help that right?
 

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Yes - provided the engine will pull the gearing. Here:

Gearing Commander: Motorcycle Speed, RPM, Chain & Sprockets Calculator

Generally a good thing to do on a highway/commute bike is work out what speed you want to be in the sweet spot of your engine in top gear, and adjust for that. My K100RS wants to be sitting at 5K rpm at 80mph in top gear, which is a good thing since shaft final drive isn't as easy to re-gear.

KeS
 

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Discussion Starter · #3 ·
well i hear people complaining about no top speed or lack or enough top speed so i was just wondering why people dont just change out the sprockets
 

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Sprockets arent always the case.. alot of factors come in .. engine, wheels, the filter and how much air its giving the bike.
 

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lol im just trying to get my posts up for some more respect. hehe.
 

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Discussion Starter · #8 ·
lol its all good. we all post whore here and there. some more than others.
 
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Whats an action that could get me banned. Perhaps posting too much in one day?

Could i just post like 500 posts on one of my own threads?
 

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Whats an action that could get me banned. Perhaps posting too much in one day?

Could i just post like 500 posts on one of my own threads?
Or you could take the extremely unconventional approach and actually post something of value to the forum, instead of just annoying the hell out of everyone.
 

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Discussion Starter · #13 ·
Because you're reducing acceleration at the same time. It's a trade-off. Go play with the gearing calculator and you'll see.

KeS
yeah ive done a lot of gearing reading when i was going to do the -1/+2 on my r1. but i didnt because i like being able to cruise under 5k easily. and i dont need the low end. thats the benefit of having multiple bikes. i have my 650r for low end and also my cruiser. my friend does have a 250r tho and i was thinking i might do a higher top speed setup for him. he mainly does straights and nothing too demanding in the leans or off the line.
 

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Spiffy...
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You lose acceleration by gearing up, through the whole range; predominantly noticeable at top end though. Gearing up offers diminishing returns, as the steeper the gearing is the more power is needed to accelerate. So, at a certain point, you will begin to lose top speed by gearing up as surely as you do gearing down. Stock gearing is chosen as a sweet spot in the range of possibilities, but there is room for adjustment.

I wish I could give you bike specific info, but I'm only familiar with the 650 in this case. I have run numerous gearing ratios, and am currently -1 in the rear. This has had a very minor impact on acceleration, but increased my gas mileage by about 2 MPG.
 

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Discussion Starter · #15 ·
You lose acceleration by gearing up, through the whole range; predominantly noticeable at top end though. Gearing up offers diminishing returns, as the steeper the gearing is the more power is needed to accelerate. So, at a certain point, you will begin to lose top speed by gearing up as surely as you do gearing down. Stock gearing is chosen as a sweet spot in the range of possibilities, but there is room for adjustment.

I wish I could give you bike specific info, but I'm only familiar with the 650 in this case. I have run numerous gearing ratios, and am currently -1 in the rear. This has had a very minor impact on acceleration, but increased my gas mileage by about 2 MPG.
oo yeah? might look into doing that on my 650 too. but i like it the way it is now. has a good balance
 

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Spiffy...
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oo yeah? might look into doing that on my 650 too. but i like it the way it is now. has a good balance
My favorite was -1 +2 :D

Acceleration was scary, and by scary I mean fun; had to worry about bring the font end up a lot. But, when you drop a tooth on the front you are going to a 14 tooth sprocket which lasts a rather short amount of time. And cruising RPM was high, mileage was low, etc.

I'm at the gearing I am due to commuting about 300 - 400 miles a week. However, I will be moving much closer to work (10 mile commute instead of 45) so.... :devil
 

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Discussion Starter · #17 ·
yeah ive driven bikes with that setup. on liters and 600s. i wouldnt do it simply because of the mileage lost and also higher revs on the engine
 
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