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which sprockets for 70mph cuising

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XR650R

i want to be able to just cruise at 70 MpH for highway, but still retain some offroad ability with gearing.

110 km/h is the Australian highway limit - which is 70 mph. Can't cruise comfortably on the highway with the gearing I have - too dark to go out and count rear sprocket teeth now but the front is a 14.

I want to be just cruising at 70MPH with any faster being too high in the revs, so that would mean I wouldn't comprimise offroad.

What are your suggestions.

What is the US highway average speed limit?

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15/45 is a good compromise. if a 16t on the front would fit nicely, i'd have the 45t on the back and have a 13t ready to go on for those tight trail rides.

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when setting up a new chain and sprockets, what setting do you want the axle to be at. If you leave no forward movement then can you still get the wheel off, if you leave no backward movement then how do you tighten the chain.

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15/45 is a good compromise. if a 16t on the front would fit nicely, i'd have the 45t on the back and have a 13t ready to go on for those tight trail rides.

XR650R

I don't want to comprimise anything for road riding, as long as it cruises at 70mph and no higher.

Is there a certain revolution speed that is optimum for sitting on.

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theres always a compromise.

The lower the gearing you choose, the less comfortable on the freeway.

personally, i'd go for a nice comfortable gearing that is comfy to get to the trails, and then just use more clutch when i get to the tracks

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i run 14/43 and cruise between 70-75mph.

i use 90 street and 10 dirt.

if you run really tight trails this won't be so good, as you'll be stuck between 1st and 2nd.

1st won't be enough, and second will be too much.

that's probably why people think 15/45 is a good compromise.

get your rear sprockets from dirttricks.com

best sprockets ever.

enjoy 👍

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Seems to me the easiest (5 mins) and cheapest ($15-$20) way to go is to change the 14T front to a 15T front. The front sprocket comes off very easy and no need to add/remove links in the chain. Plus, it's just a 5 minute job to change back, if so desired.

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Seems to me the easiest (5 mins) and cheapest ($15-$20) way to go is to change the 14T front to a 15T front. The front sprocket comes off very easy and no need to add/remove links in the chain. Plus, it's just a 5 minute job to change back, if so desired.

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No, 14/48 is stock. 15/48 will run at 70mph alright, but if I was gearing to run that fast all the time I'd probably drop at least one or two more teeth in the rear.

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I have just priced up a new set for my XR650, without specifying sizes the guy in the shop said I'd need a 15/41 combination. I'm guessing that's standard in Oz.

Does that seem a bit tall?

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15/41 does not seem too tall. I run 16/44 all the time and that is the same ratio. I think I cruise at 70mph @ 4000rpm and top out around 115 or so. Just be ready to clutch it a little in the extremely slow tight stuff.

Or just have really smooth throttle control to keep the bike from stalling at idle speed with the clutch out. This is my preferred method. This bike tractors around really well.

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So, is 14/45 stock?

14-48 is stock. I run 15-40 on the street, 4650 RPM's at 70 MPH. with that gearing the bike runs great at high speed, but it does loose a lota low end/off-roading capabilities.

I went from 15-45 to 15-40 because the 15-45 was buzzy at 65+...

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14-48 is stock. I run 15-40 on the street, 4650 RPM's at 70 MPH. with that gearing the bike runs great at high speed, but it does loose a lota low end/off-roading capabilities.

I went from 15-45 to 15-40 because the 15-45 was buzzy at 65+...

Is that on dirt tires or the 17s?

That is the gearing I run in sumo trim.

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Is that on dirt tires or the 17s?

That is the gearing I run in sumo trim.

Yes with 17's. I swap out wheels and gearing, i go from 14-50 off-roading, to 15-40 supermoto. Scary diffornce:crazy:

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15/41 does not seem too tall. I run 16/44 all the time and that is the same ratio. I think I cruise at 70mph @ 4000rpm and top out around 115 or so. Just be ready to clutch it a little in the extremely slow tight stuff.

Or just have really smooth throttle control to keep the bike from stalling at idle speed with the clutch out. This is my preferred method. This bike tractors around really well.

Err, what's it like at 115 (mph?) with knobby tyres, does it vibrate a lot? What tyre combo is suited to that sort of speed and trail use?

My worked 600 has the 14/45 and has no trouble getting to the speed limit and beyond but it's just too uncomfortable due to the vibration . I thought it was the Mich AC10 rear tyre.

How many guy's balance their wheels?

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Dunlap D606 in the rear 130/90-18 and a Kenda something or another up front. The are not balanced but probably should be, at certain speeds you can really feel it.

Knobs at 100+ on pavement are interesting. Knobs on dirt at about 97 on the gps feel right at home!

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im amazed at the speeds you guys claim your bikes are going:prof:

Mine with 17's and 15-40 gearing will not top 106 MPH on a flat surface, and ive had it going 113 with a very steap downhill grade. And that 15-40 is tall gearing!

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I've hit 102mph GPS on a gravel road with LOTS of wheel spin and 15/47 gearing. It was still pulling hard (or just spinning harder) when we backed out of it (there were two of us on our 650Rs side by side). I can cruise down I-90 on the way to work at 85mph plus without too much difficulty. It is a little buzzy, but the sustained buffeting from the wind at that speed is more annoying than the motor. I did have one of the guys at work try to race me down the frontage road with his car. I was still pulling away when he hit his limiter at an indicated 105, so with those things usually being off somewhat I was probably at least at 100 and still accelerating.

Typically I run stock in the dirt (14/48) and switch to 15/47 when I am going on a more D/S oriented ride or commuting to work (35 miles). With that gearing swap I don't have to touch my chain adjusters; it is just bolt and go.

Speed limits where I am at are 75mph on freeways, 70mph on two lane secondary roads, and 45mph on unpaved secondary roads.

I balance all of my wheels.

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