Changing sprocket for better trail riding.....

I'd like to make my XR400 easier to control in first & second gear for negotiating narrow trails and doing single track. Looks like the stock rear sprocket is 45 tooth. What's normal practice? Will going from 45 to 48 make a noticable improvement?

Do I need to be concerned with the chain when putting on a bigger sprocket?

I'm a fairly new rider, the XR is my first bike and has plenty of power so I'm leaving it "corked" for now. I'm liking the slow speed narrow trails riding (woods?), no plans for any high speed desert stuff, but I do ride the bike around the city streets a little.

Any recommendations y'all can provide would be appreciated.

Go down one tooth in the front sprocket from a 15 to a 14 that should help I woulldnt go any lower than a 14 for the front though. :)

I found that a 48T is perfect for the XR440. I don't like going down on front because it causes faster wear on parts.



I'm with you and Dwight on this one. I went to a 47 in the rear and left the front. You do need to go to a longer chain. Just buy the one size bigger and you will be fine. (Sorry I don't remember what stock size is right now) I ride mostly tight woods and it's great. Most of the time I can stay in 2nd and just ride. And the bike is still plenty fast for me out in the open. You do have to shift a bit more but it pulls like mad. And 3rd gear wheelies are fun.

My rear sprocket is Sprocket Specialist and the front is Primary Drive with a RK X-ring. I paid total of $80 for everything. Rear sprocket from and the rest from Rocky Mtn. I'll probably just buy all steel next time for the wear issue.

Going from a 45 to a 48 on the rear should require a chain with 2 additional links. I agree this is better than making the front smaller.

I have both a 14 and 15 front, and a 45 and 48 rear that I can play with. I've tried all combos.

1)14/48(3.40:1) If you are riding in the really reallt tight stuff(Flynall's Goat Trails), then the this works great, but it's like there isn't a 5th gear, as you are there too quick. Max speed on this set-up is about 61 MPH at the rev limiter.

2) 15/45(3.00:1) I ran LA-B2V with the stock gearing; all desert, and that was just fine, but wind resistance, and aerodynamics played into effect on failing to get a top speed. Well into the upper 70's though. I don't like to tuck it on desert terrain. :D

3) 14/45(3.21:1) or 15/48(3.20:1) If you want a little more bottom end with about 69-70mph top speed, then go with either, as you'll find that is a great compromise with the 5-speed box we are stuck with. I do like the idea of a larger front sprocket for wear purposes, but depending on your chain length, it might make a difference on the snail scroll adjusters where they sit. I wish the bike had a 6-speed. :D I'll leave this set-up on now, for some time to come. :D

I've heard some say they can tell the difference in a 15/47(3.13:1) and a 15/48 rear sprocket. That's like a new rear tire versus an old tire.This all depends on the terrain you are riding on. As it's been said before, the sprockets are cheap, and would be good to at least have another to "swap" out for different types of riding areas. :)

Hope this helps. :D

Go with a 14 on the front and leave the rear won't have to do anything with the chain -- so it's a quicker and cheaper fix (than changing the rear and adding links) to see if you like the gearing.

Also, there are no real wear concerns from dropping a tooth in the front (ask any reputable Honda mechanic). Plus, you're not racing the bike, so at your level of riding, dropping to a 14 will be just fine. I am currently running this setup -- you'll notice a significant torque increase in every gear (especially 1 thru 4), and you won't miss the relatively minor top-end sacrifice in the tight trails.

By the way, once you get a little more used to the power of your bike, I would recommend uncorking that baby...let it breathe! The XR4’s come off the showroom floor so corked-up it’s ridiculous. Consider going with an FMF Q Pipe (delivers the power without the noise), FMF Powerbomb Header, Re-Jet, add UNI air filter, and remove snorkel...The difference is NIGHT AND DAY!!!

I've ridden a 15/49 combination, which is nice.

I put a 14 tooth on the front. It is easy to change and 14 tooth sprockets doesn't seem too small to me. Not compared to the 12 or 13's that the XR/YZ/WR 250's run. As always, I'll defer to Dwight's expertise.

I've had a 14 front on mine over 3 years with no problems. Chain slider is still in good shape. However, I would not go to 13. I currently run 14/47 with stock chain + extra master link. This is usually not recommended but at the time I did the swap, the chain was still almost new and I didn't want to scrap it. This gearing would be too low if you ride street much. You'll definately see a difference tho with just a 14 front or just the 48 rear for trail work.

I followed Dwight's recommendation last spring and went with the 48 SunStar steel sprocket and had to add 1 link to the stock O-Ring chain.

I had read here on TT where those in the same position added an additional master link to accomidate the need for one more link with no problems. I went this route and have suffered no ill effects.

Inexpensive fix.

The 15/48 combo is great, you'll love it.

3) 14/45(3.21:1) or 15/48(3.20:1) If you want a little more bottom end with about 69-70mph top speed,

Corey, All my XR435cc - 440 cc bikes with no cam work but a pipe rejetted or with Edelbrock carb, would do about 83mph with a 15/48 combo with a Pirelli MT16 450X18 on rear. I wouldn't hesitate to go to a 49T with this tire on a stock bike. But you should still get over 80mph. Sounds like you have a problem.


I can definitely feel the difference between a 15/45 and 14/45 setup. I only run the 14/45 when I'm in the mountains. It definitely adds more grunt. I recently went back to a 15 tooth front and have 45 and 48 rears. I've never heard of having more wear by changing the front sprocket. I can only guess that the motor is spinning a lot more to move the bike, but I don't really see where it could cause that much more wear. Anyone care to elaborate on this?


Larger sprockets put less strain on chains. Really small sprockets, such as 12 or 13 tooth sprockets put the most wear on them. From mtn biking, I know you want to run the larger sprockets on both ends.

The other wear item is the swingarm slider. With bigger sprockets, the chain runs farther away from the swingarm slider block. Less contact, less wear.

Many thanks to everyone for all the great tips and advise. :)

3) 14/45(3.21:1) or 15/48(3.20:1) If you want a little more bottom end with about 69-70mph top speed,

Corey, All my XR435cc - 440 cc bikes with no cam work but a pipe rejetted or with Edelbrock carb, would do about 83mph with a 15/48 combo with a Pirelli MT16 450X18 on rear. I wouldn't hesitate to go to a 49T with this tire on a stock bike. But you should still get over 80mph. Sounds like you have a problem.



Maybe It was 80-something, but the end of the road was coming up reeeeeeal fast. I know the lower gearing maxes out at around the 71 range, so I must be off. Vision blurred at those speeds? :)

:D What's this on the graemlin board? I think we can get rid of the non-moving ones like :usa: :usa: :D :D :usa:, and keep the :D :D :usa::D:usa: ones!

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