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Changing sprockets?

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I ride a 2000 XR400R. I want to go bigger on the rear sprocket. I mostly hillclimb and ride single track trails. Can anyone tell me what sizes to use and a good brand?

Thanks!!

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I did a lot of research on this recently, and decided to go with a 48-tooth rear sprocket (stock is 45 teeth). Dwight Rudder recommended this size, and I figure he knows what he's talking about. I should be able to lift the front wheel easier, and stay in 3rd gear more often (the trails I ride require a lot of shifting between 2nd and 3rd).

I bought the Ironman. They're supposed to be one of the best made, very long-lasting, but they ARE expensive (~$100 for mine). They look cool too, with high bling factor. Also, you should buy a new chain and front sprocket too if you're getting a new rear sprocket -- buy all 3 new, at the same time.

If you go with a 48-tooth rear, I've heard you need to add an extra link to the chain because the standard size (120 links?) is too short... I bought an extra master link to serve this purpose -- still not sure if that will work, but I'll find out.

(I can't actually tell you how good the 48-tooth is, as I haven't installed it yet. Just got it last week and haven't had time to put it on).

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up three on the rear is equal to down one on the front. if you are just keeping the 15 front and going to a 48 rear. just change the front to a 14. you won't need a new chain

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Go with Ironman sprockets, I have them on my bike, and had to use my old worn out chain for about 4 rides, they still show no wear. I have probably put about 20-25 hours on the sprockets, and they are still in perfect shape. if your sprockets and chain arent worn, just buy an ironman front sprocket, its worth it.

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If you have your heart set on the 48 tooth then you can choose any stock replacement for an XR650R (since it is the same bolt pattern and ships with a 48).

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i just bought a 14t and a 45t

with the 45t on the rear, i can just swop easily with either the 14t or 15t

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With hindsight and all this good advice, it sounds like I should've gotten a 14 front and new Ironman 45 on the back... I like your idea about that combo keeping you more flexible, since it's easier to change out the front than the back.

Ah well, live and learn. :)

Hey, does going smaller on the front increase the wear on your slider, from the chain?

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xrmike, a 14 won't show much more wear than a stock 15 but a 13 or 12 might. I have run the 14 alot and don't notice enough to worry about.

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With hindsight and all this good advice, it sounds like I should've gotten a 14 front and new Ironman 45 on the back... I like your idea about that combo keeping you more flexible, since it's easier to change out the front than the back.

Ah well, live and learn. :)

Hey, does going smaller on the front increase the wear on your slider, from the chain?

I was warned by many that going to a 12t front on my XR250 would cause slider wear problems. I've been running a 12t front for about 18 months now and the slider still looks great (around 3,500? miles). I would not worry at all about a 14t on an XR400. I did have to replace the chain and sprockets about a month ago (Sprocket Specialists front sprocket was wasted). I'm now using a PBI Racing 12t and SunStar rear with Renthal R1 chain so I'll see how this combo works. I may end up replacing the setup soon with a 13/52 since I went to the 280 kit.

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Hmmm. I have always been able to pull taller gearing with a 280 kit. I like running 13/46 or 13/45; My best friend likes running a 14t countersprocket instead - 14/48. You won't have to shift as much and as I said it will "pull it" (unless you weigh more than 240 pounds...).

- jeff

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I Ride A 2000 Xr400r, And The Sprockets Are Stock. What Would Happen If I Went Down 1t In The Front And Up 3t In The Rear?

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Hmmm. I have always been able to pull taller gearing with a 280 kit. I like running 13/46 or 13/45; My best friend likes running a 14t countersprocket instead - 14/48. You won't have to shift as much and as I said it will "pull it" (unless you weigh more than 240 pounds...).

- jeff

Where I ride I have no need for top speed. I don't have anywhere where I can run 6th wide open so I gear the bikes down to where the gears are usable. I like a very low crawling gear, I run 2nd/3rd/4th in the tight stuff which leaves 5th/6th for getting me from trail to trail. I've found with the 280 kit I am in 3rd/4th much more, still use 2nd a little and even bump into 5th once in a while. I'd rather be slightly low in gearing than slightly high and I'd guess 51/52 on the back with a 13t front should do the trick. 13/50 is still to high for my liking.

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litrob, you will just get more torque and less top end speed. 1 down on the front = 3(approx) on the rear.

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Does anyone run anything bigger than a 48t rear, and if so did you leave the front stock?

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