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Close ratio kit?

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I have a 97 CR 250 and was wondering if anyone made a close ratio kit for these bikes. Everyone I ride with has at least 2 gears on me, and top speed might be pushing 45MPH.

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I got a couple of questions. Is the bike jetted ok, and are you running stock gearing? I have a 02 with a 51 13. I'm still getting speeds way above 45. I thing stock gearing is a 13 49. With the lack of low end and my size (200 lbs) I dropped the gearing for a little more bottom end.

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Jetting is great, gearing is 13-51. I will be in 3rd gear when everyone else is just getting out of first.

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My brother has a CR 250 also, and a friend has an RM 250. I know that the CR is a wide ratio, just wandering if someone made a kit that was closer for some reason. I dont want a wide ratio just want it to be normal is all.

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No, the CR is a close ratio. The gearing maybe different than the RM, but I do believe it is still a close ratio. Someone used to make a wide ratio for the CR a few years back, but not any more.

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Let's see:

The CR should be able to turn 8000 RPM, and it has a primary drive ratio of 3.0, and you are running 13/51 or 3.92, and your rear wheel has a diameter of 24 inches, that means your speeds should be:

1...27

2...33

3...40

4...49

5...55

So it seems to me that you need to switch to 48 rear.

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If you want a closer ratio close ratio the CRF450 trans should work, but it sounds like that is not what you want.

If you are in 3rd and everyone else is still in 1st then you are either lugging your motor or should be running closer to stock gearing.

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what the hell is going on around here???

your not gonna get more speed out of a close-r ratio tranny. the cr has a close ratio tranny. you go closer, than you'll be in 5th while their still in 1st.

however, something seems very odd here. I'd drop a few teeth from the rear and see what happens.

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Yes it is a close ratio trans. and no i don't want to go to a wide ratio. Everyone I ride with is 2 gears below me. It is weird cause ill be in 5th gear riding and they are usually in 3rd. I have heard that someone made an even closer ratio tranny, for some reason im not sure why but its the only thing that makes since. I don't think that dropping 3 teeth on the rear is going to make that big of a difference. But i will give it a shot.

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Except it doesn't make sense since if your ratio was even closer you would go even slower. Everyone else either has way different gearing, or a wider ratio tranny than you. Or possibly someone is riding a 4t and you didn't notice? Why do you think enduro/off road bikes have a medium or wide ratio tranny? So they can get more top speed than would be required on motocross bikes. Then they change their gearing as needed for the terrain they will be riding. If changing sprockets didn't actually make a difference, then I doubt so many people would waste the money on it.

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one of us is high and has it backwards. a close ratio tranny means your gears are short and close together, meaning you would need to be in a higher gear to obtain higher speeds.

mx bikes have short gears so you get quick acceleration = close ratio trans, they dont need to go 85mph, but they need to get to 50 real quick. If you go closer than the already close ratio stock trans, then your not gonna get to 50, but you'll get to 30 in no time.

if your bike is topping out at a slower speed than you want, you need taller gears. not a close ratio trans, that would get you the opposite results of what you are shooting for. a closer ratio trans is gonna top out at even a lower speed.

am I trippin out on pcp here?

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I dropped a couple teeth and thought I was on a different bike.

KC, thank you for validating that, I was about to go outside and slap myself a few times.

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