Naru

XR650R Stock Top Speed?

17 posts in this topic

I finally got around to installing a Trailtech on my second XR650R, and took it out on the road with stock gearing/HRC tip/Uncorked/Unsmogged/Otherwise stock. The Trailtech matched a friend following in a car, clocking the bike at a top-speed of 85 MPH with knobbies. So, I figured I'd ask, is that normal? Compression was at service manual spec. Since my first XR came re-geared, I'm not sure, and I've heard numbers of stock XRs topping at ~100 by people on this forum. Since I'm the second owner, I suppose the sprockets could have been changed, but they definately looked like the stockers. Thanks!

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my 2003 came with 14 in the front and 48 in the rear. I havent found a place wide open enough to open it up past 3rd gear :thumbsup:

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I have had mine up to 95 on a dry lake bed with a mounted GPS and I think there was a little more to go but my brain ran out of room. This is with the stock 14-48. I put a 15 on the front and I know it will easily break 100. If your not careful, you can break a few other things as well! :thumbsup:

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I got radared by a CHP at 94 mph and I had 14 48 gearing. I do not think I was at max speed. My bike is stock but uncorked with the HRC tip. I have DOT legal tires on it. Thank the Lord that I got off with only a 75 in a 65. :thumbsup:

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If I recall correctly top speed on a dry lakebed was 99.7 according to GPS. That was with the standard uncorking,emissions block-off, 178 main, and 14/48 gearing. I'll be back at Mojave this November with quite a few more mods and I'm anxious to see what the new speed will be. :thumbsup:

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This is on a pretty-much stock bike, with what appeared to be stock gearing (but I didn't look hard). The previous owner didn't look like the one to change anything, but I'm going to check, as 85 sounds very low. :thumbsup:

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This is on a pretty-much stock bike, with what appeared to be stock gearing (but I didn't look hard). The previous owner didn't look like the one to change anything, but I'm going to check, as 85 sounds very low. :thumbsup:

If your bike is not uncorked that speed might be about right. If it still has the stock baffle and jets I would uncork it. It was intended to be uncorked. The power and performance is night and day uncorked/corked.

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yeah, well 14/48 is stock gearing, and if the bike is properly uncorked and jetted correctly, it should run 100mph top speed, or somewhere close, depending on a few other factors such as wind, temp, rider weight, etc.

My bike with the stock gearing and stock knobbies clocked 99.6mph at a friend's airport on his grass runway (GPS measured).

Something is not right if the bike can only do 85.

LL.

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The bike was fully uncorked, with HRC tip. Hmmm.. well, I'll go recheck the gearing then. Otherwise, I guess it's time to break down and send the engine to Barnums. :thumbsup: Thanks everyone for the help.

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The bike was fully uncorked, with HRC tip. Hmmm.. well, I'll go recheck the gearing then. Otherwise, I guess it's time to break down and send the engine to Barnums. :thumbsup: Thanks everyone for the help.

Not necassarily, Qadsan pointed out if your sprockets have been changed to say a 13 tooth front drive sprocket, 85 mph would be about right on. Or if the rear sprocket was changed to a 51 tooth. You see if the previous owner uncorked the bike he may also of had it geared lower for working in tight conditions such as mountain trails. I have mine set up that way myself. Check the sprocket sizes first and also check the main jet. Even uncorked if the main jet is too small you will not get full potential from the bike. The main jet should be anywhere from a 172 or bigger unless he rode at high elevation. In that case the jet will be smaller. Which would not perform well for speed at lower elevations.

I would always check the cheap fixes before pouring a lot of money into it.

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If you do the math top speed for the XR650R uncorked @ 8200RPM is 99.7mph...with a bigger tire (taller then stock)on pavement slight down hill I could cycle the rev-limiter at 102.2 on the GPS dry lake bed was 100.3 at the best most of the time was 99+ couldn't get to the rev-limiter in the dirt. I ran this many times to get a good reading. I have a Baja deings speedo that is 5mph off so, at first I thought I could get the bike up to 106 running next to John Robberts but, the GPS dosn't lie to often and the speedo is off. I think you might want to check your against a GPS :thumbsup:

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Otherwise, I guess it's time to break down and send the engine to Barnums. :lol:

Holy cow, don't get me thinking about this again :lol:. I was just on the phone with him tonight to setup an appointment for him to do some suspension work on my CR250 and a friends CRF450 next month and I couldn't resist bringing the 680 topic up...again. Ever since I rode his bike I can't get it out of my mind :thumbsup::devil::awww: His bike easily pulled mine in any gear at any speed and his was geared much taller than mine. He said another team in Mexico clocked him in their vehicle at 120 MPH in the whoops :D. I may yet end up with a Barnums 680 special one of these days :lol:

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He said another team in Mexico clocked him in their vehicle at 120 MPH in the whoops :thumbsup:. I may yet end up with a Barnums 680 special one of these days :awww:

Damn.. Even if my bike could do that, I don't think I'd want to try. By the way, how much does an engine like that cost, anyway? Probably more than my bike did, by a long shot. :devil:

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I'll let you know whem mine is done. I am having three gears changed so, it's hard to know just the engine work

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Alrighty thanks for the input guys.

 

Edit: Sorry for replying to old thread. Am on my phone and didn't see that I was posting on the wrong thread!

Edited by Justn1k

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