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Sprocket sizing....

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I have a 2008 450 excr that has the stock drivetrain, 15/45. I'd like to be able to crawl up and down hills and technical trails, what would be the best setup for that?

From what I've read I was thinking 14/52...???

Letting my mouse lead the way I bought a 14t front sprocket thinking that would help, but I'm guessing that will make it worse.

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no you made the right first call. dropping a tooth in the front will definitely reduce your top speed and give you more snap and power at lower speeds for the gearing. you can try a 13 as well if the 14 doesn't give you enough low end grunt. if with the 13 you still don't have enough then i'd go up in the back to get even more. but you're definitely on the right track.

so mount up that 14 and see how it feels.

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That's what I thought originally but looking at it won't the smaller front will spin faster?

I just put it on after futzing with the damn rear disc guard. So, if that's the way to go then I'm guessing that the 14/52 will be what I want (or 14/54). I have little interest in gong fast, I just want to be able to creep up or down if I have to.

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That's what I thought originally but looking at it won't the smaller front will spin faster?

I just put it on after futzing with the damn rear disc guard. So, if that's the way to go then I'm guessing that the 14/52 will be what I want (or 14/54). I have little interest in gong fast, I just want to be able to creep up or down if I have to.

well it's going to spin at whatever rate it does for the rpm and gear you're in at the time. the different sizes of sprockets just dictate how long it takes for the chain to go around it. so with the smaller c.s. sprocket it will lower you're top speed and improve low end grunt. the inverse of this is true for the rear sprocket, the larger you go on the back the lower your top speed will be and the more low end you'll gain.

i don't know about your particular bike but normally about 52 on the back is as big as you can go until you start running into clearance issues with the chain guide. i know that some guys will drop their c.s. sprocket down to a 12 but that makes a pretty tight radius for the chain to run around and again you may experience wear issues on the chain slider and swingarm. so i would say that 13/52 is about the lowest gearing you want to go just from a wear perspective.

if you haven't tried the bike with the 14 yet you should give it a shot before investing in the new rear sprocket as dropping a tooth in the front is similar to adding 3 in the back. it will make a big difference.

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Thanks for the clarification, I'll give the 14 a shot and see how it goes. I read in other posts that the 14/52 works pretty well and didn't require messing with anything else.

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I too ride a 2008 450 excr. 14/52 are excellent for trails, 3rd gear wheelies with just a turn of the wrist, a little low for street use but you can still cruise 55 but not over 60. I wore those out and went to 14/50, still really usable for trails but 2nd gear is just a tad tall and I ride in 5th quite a bit on the pavement. I have since wore those out and will probably do 14/51 next. Good luck.

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I like the 14/52 on my 530 along with ignition switch/unplugged wire for the real tight stuff. No more flame outs in the real technical stuff anymore, it just grunts along like a tractor.

The unpluged ignition wire makes a big difference for me. It tames the throttle so those low gears can get some work done.

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I'm a new rider so speed kind of freaks me at the moment! Also mine is still corked, I have no power problems, just want to be able to walk up hills in control. It is plated but I don't have a MC license yet so no street travel.

4strokeridertt, what's that bit about the ignition switch?

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I'd like to be able to crawl up and down hills and technical trails, what would be the best setup for that? .

I love 13/50 on my 450EXC for tight trails and technical hill climbs. I have a second wheel with a 48T and don't like 13/48, not low enough.

Watch how slow I can go with no clutch work.

And the fast section above the climb is over 45mph in 4th without over reving it.

2-stroke guys can't believe it's possible to crawl up rocks that slow.

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On the front left side under the tank is a wire which when unplugged retards the ignition timing just a bit in the low RPM's. You can fit a switch to it and set it to off for the real tight stuff. It makes no difference after about 1/3 throttle, it just softens the hit right off idle.

Do a search and you will find a lot of info.

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I also vote for 14/52 for the tight gnarly stuff. And it won't wear out the chain slider as fast as a 13.

OOps... edited. hahah. I meant 14/52

Edited by smithpa68

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On the 08, you can go as low as 13-48 with your stock chain. That's what I have been running on mine, but it is still a little gappy between 2nd-3rd for my liking and with hills added into the mix. I have a 13-50 combo with a new chain I'm putting on tonight for my ride tomorrow... braaap, oops, I mean bwaaaaaa.

-Jon

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I wish I did a bit more research, I already bought and installed the 14t, I guess I'll just get a 52 and see how it goes.

Thanks 4strokeridertt for that mod!

DrKayak, that vid looks pretty crazy! That's definitely the speed I'd like to shoot for, I'm definitely not ready to hit those tight trails at the moment either. I'm guessing that you're not in SoCal. Also surprised you can be on trails with bicycles and hikers too.

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Like all of these guys I have my own favorite. I have an 05 450 EXC-R. I originally went with 14/52 but have since changed to 13/52. I like the crawl a little bit better for the tight stuff. Also my bike doesn't see the pavement much but if it does it is just a go through town type of thing. A quick run down the gravel you can still hit 70 but you would not want to stay there for long. I would say 55 is top run speed! This is the perfect combo for myself.

As far as the change goes you will definately have to put on a new chain but I am still running my same guides.

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Weekend Rider, can you just shorten the chain...like on a bicycle? I'm going to get the 52 soon and at least the 13 is pretty cheap.

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I am able to use stock 14/50 and 14 /52 with the same chain length. You have to move the adjuster pretty darn far, but once you get the length right you can switch back and forth with the same chain. Try moving the adjusters a bit. I was surprised myself that it worked.

I had the stock 14/50 in Baja as a pre runner. So when I got back home to Atlanta, I didn't want to toss the chain. I only rode my bike for about 300 miles while I was there. I was able to move the adjuster block forward enough to use my trusty 52 tooth. (your mileage may vary of course)

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smithpa68, how'd you get your bike to Baja safely? I'm assuming you're talking about Mexico.

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Yes. Mexico. :lol: See the website in my signature for the whole story.

Our local dealer saved some KTM Super Enduro crates bottoms for us. I had a friend that has a wood shop that makes Tim the Tool Man look like an amateur. So he built some crate tops for us that bolted on the bases. It worked out perfect. We put three bikes in three crates and all our spare wheels zip tied into the crates as well. The we just used a freight company business to business. PromotoSports KTM in Canton GA was our sponsoring dealer and arranged with a dealer out in California to receive our bikes. They were awesome to help us out that way.

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