2006 yzf 250 top speed
- Thread starter 11brianm
- Start date
Based on a 02 YZ250F spec (and I doubt that they changed the ratios much from 02 to 06)..
If you were actually able to get the perfect conditions, no wind, prefect flat surface, etc...
And you some how were able to overcome wind resistance..
5th gear @ 11500 rpm's with the gearing you claimed you had in your first post, 52 rear.. (40 tooth.. yeah right.. whatever) and figuring you probably have a stock 13 on the front, you'll get a whopping 66.2 out of it.
If by some stroke of luck, you're able to find a rear gear in a 40 that will fit that bike, (which I doubt, but whatever)...
40 rear x 13 front @ 11,500 = 86 mph
40 rear x 14 front @ 11,500 = 92 mph
36 rear x 13 front @ 11,500 = 95.6 mph
36 rear x 14 front @ 11,500 = 103 mph
But.. even if you can do all of the above, that bike was not designed to go that fast. It would not be stable enough to hold on. You will crash, and likely kill yourself.
When you do this, please make sure you get a friend to record it on video so that your parents will understand that it was you that got you killed, and they won't try suing anyone.
If you really feel the need to go fast, get the right equipment.
(Rich, feel free to correct my calculations if you feel like it..)
If you were actually able to get the perfect conditions, no wind, prefect flat surface, etc...
And you some how were able to overcome wind resistance..
5th gear @ 11500 rpm's with the gearing you claimed you had in your first post, 52 rear.. (40 tooth.. yeah right.. whatever) and figuring you probably have a stock 13 on the front, you'll get a whopping 66.2 out of it.
If by some stroke of luck, you're able to find a rear gear in a 40 that will fit that bike, (which I doubt, but whatever)...
40 rear x 13 front @ 11,500 = 86 mph
40 rear x 14 front @ 11,500 = 92 mph
36 rear x 13 front @ 11,500 = 95.6 mph
36 rear x 14 front @ 11,500 = 103 mph
But.. even if you can do all of the above, that bike was not designed to go that fast. It would not be stable enough to hold on. You will crash, and likely kill yourself.
When you do this, please make sure you get a friend to record it on video so that your parents will understand that it was you that got you killed, and they won't try suing anyone.
If you really feel the need to go fast, get the right equipment.
(Rich, feel free to correct my calculations if you feel like it..)
Makes you wonder, about the posts that do not make it this far!
About every 6 months, you get the kids, who's is faster, how mph does my 80 go, and on and on. From people who can not negotiate a turn in the dirt in anything but first gear,5~10 mph? Maybe they started dirt drag racing as a sport, and nobody told me? Do you suppose there is some kind of reasoning to make it as fast as possible off idle, and sacrifice top speed? Nope, enter bizzarro world, 200 mph 250f mx bike, for what/who cares?
11brianm said:
It's possible to GEAR it to do 85, just like it's possible to gear it to do 100. Pulling that gear at the rpm required is another matter entirely.
Instead of cutting class to smoke weed behind the dumpsters, you should have stuck around and listened to the physics lecture. You'd be surprised how much of it translates directly to what we do with motorcycles.
You seem fairly content to bask in your mind numbing ignorance, so enjoy! :|
When I refer to a fast bike, it is not the top speed Brian. Its how fast it can get there that matters. If I can get from zero to break my neck speed, the quicker the better. I will sacrafice the top speed, who uses it? Maybe a quad guy? The bike will not pull when you go using reverse gearing. 13,500 rpm, you will be lucky to see 800 rpm, it will not pull it! Now if you redesigned, the crank, and transmission gears, and the final drive$$$$$ It is easier to get a trail or street bike.
helio lucas
~SPONSOR~
- Jun 20, 2007
- 1,020
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hey 11brianm... if you really want it, i recommend a book with great, great info about gearing, max power, power curves and top speed... it has a chapter only dedicated to this...
http://www.amazon.co.uk/Racing-Motor-Cycle-Technical-Constructors/dp/0951292927/ref=pd_bxgy_b_img_b
http://www.amazon.co.uk/Racing-Motor-Cycle-Technical-Constructors/dp/0951292927/ref=pd_bxgy_b_img_b
Deadohiosky39
Member
- Jul 12, 2008
- 146
- 0
Anyone remember the Terrafirma (1 or 3 not sure which) videos with Campbell out in the desert on an XR with the helicopter overhead? It said he was going 100mph but who knows.
I agree with everyone else there is no way you are going 85 mph the way you are set up now and it's a lot harder to go from 85 to 100 than it is to go from 60 to 85. You would be better off starting with a 450 to begin with and even then it wouldn't be easy.
You have a dirt bike with street tires and you want it to go 100mph. Why don't you just buy a street bike? You can find a used bike pretty cheap and then go kill yourself on that. It'll save you the hassle of trying to do it on your yzf.
I agree with everyone else there is no way you are going 85 mph the way you are set up now and it's a lot harder to go from 85 to 100 than it is to go from 60 to 85. You would be better off starting with a 450 to begin with and even then it wouldn't be easy.
You have a dirt bike with street tires and you want it to go 100mph. Why don't you just buy a street bike? You can find a used bike pretty cheap and then go kill yourself on that. It'll save you the hassle of trying to do it on your yzf.
This reminds me of a little exhibition that was done last year on December 31st 2007.
Robbie Maddison needed his bike to jump 320+ feet.
He said that he needed 80+mph take off speed, or he wouldn't be able to do it.
Did he get a geared out 250F to do the job? nope, did he get a geared out 450 to do it? nope.. Although the 450 would have handled it fine, he opted for a Service Honda CR500AF for the task.
And if you watch the video, he barely made the speed he needed to do the job.
Like all of the old men here with decades of experience in life and all things motorcycle are trying to tell you, young man, you're chasing a fantasy. This nonsense might play over at thumpertalk or myspace, but we tend to trade in reality here.
Thanks for playing along.
Robbie Maddison needed his bike to jump 320+ feet.
He said that he needed 80+mph take off speed, or he wouldn't be able to do it.
Did he get a geared out 250F to do the job? nope, did he get a geared out 450 to do it? nope.. Although the 450 would have handled it fine, he opted for a Service Honda CR500AF for the task.
And if you watch the video, he barely made the speed he needed to do the job.
Like all of the old men here with decades of experience in life and all things motorcycle are trying to tell you, young man, you're chasing a fantasy. This nonsense might play over at thumpertalk or myspace, but we tend to trade in reality here.
Thanks for playing along.
Allow myself to introduce myself. I am Dr. Armand Skagerakk Frederickshaven Chesterfield Neshenskanovich Fazzeldoctinhoffer, III. As you can see by the many names I have and the Roman numeral following all those names, I am quite intelligent. I stumbled across this discussion, this, "orgy of mental retardation", while seaching the web for the elusive elixir, Totally Awesome Sweet Alabama Liquid Snake. Being a doctor of many disciplines, I thought I would clarify the situation with the following: It should be clear to anyone with a 3rd grade level education that this endevour is impossible to achieve. So, you think you are smart? That you know many words? The only thing you need to know, for the rest of your lives is, "Totally Awesome Sweet Alabama Liquid Snake". Good day.
Dr. Fazz, can you share with us your distiguished academic acheivements?
Ol'89r
LIFETIME SPONSOR
- Jan 27, 2000
- 6,958
- 45
11brianm said:
Brian.
Don't let these guys bug you. You know how internet experts can be. :nod:
Some of us are new at this stuff. Could you please let us in on some of your speed secrets???
Did you do all of your own engine work? What cams are you running and what cam timing? Did you regrind the cams yourself or just go buy some? Did you do your own port work or have someone else do it. Are you using Arbider buttons on your pistons or stock pistons? What compression ratio? I have found the 16.2 to 1 ratio pistons work good if you can find a high enough octane pump gas.
Did you change the stock gigzillerator valves over to the unobtainum ones? And what compound did you use to lap them in?
How about your crankshaft. Are you running the beryllium crank from Crankshafts-R-Us or still using the stocker?
Sorry for all the questions but, some of us would like to know what it takes to make a twofitty go that fast.
Thanks in advance.
High Lord Gomer
Poked with Sticks
- Sep 26, 1999
- 11,788
- 35
Brian, don't let the haterz get you down. They're just too scared to do what I have done and what you will soon be able to do, too!
It was a bit harder for me, and I only managed to hit 82, but I did it on a fully tricked out KDX80. Everyone told me it couldn't be done, but my neighbor is a mechanic and he board it waay out and put 3 powerbands in it. The first time I got it into 6th gear (you might want to look at a KDX tranny to see if you can get an extra gear) and that 3rd powerband kicked in...WHOAA! I about sheet myself! Even then, it was only good for 68. I then found a 18 teeth front sprocket from a street bike. It didn't match the shaft thingie coming out of the engine, but we ground it down some and put the bolt on with superglue. I still only was able to go 76 until I found some of the secrets of weight and wind. I took off the fenders, well, the rear was broken off already, and the crossbar pad, the muffler, the brakes, and the air filter. That got me up to 78. At that speed the awning thing on the front of my helmut was bouncing around alot so I took it off and found it was quieter and could slip through the air faster with the helmut turned backwards and me crouched down real low. Got to be careful crouched down like that, tho, becuase when you hit bumps it can hurt certain parts if your a man, but it can feel good too so it all depends on what you like I guess. With the helmut fixed and me crouched down I was able to hit 79. Then I realized how much all of my clothes weigh and I tried it without them and I got up to 80. I then realized that part of that was because my back was more slippery in the air than my clothes, so I shaved my back, well, I didn't, I had to get my neighbor to help me, he's real friendly, so after that we was finally able to hit 82. We then figgered how much weight we could save by taking the gas tank off so we plumbed up a coke bottle with just enough gas to make one run, kinda like the drag racer guys do. Only problem was the Coke bottle leaked and the gas sprayed all over my parts that I didn't shave and some got on the end of the tailpipe where the muffler wasn't anymore and it caught me on fire. Once I heal up good and the next time my mom's not home, we're gonna try it again, but this type my neighbor said he has a beer can that won't leak like the coke bottle did.
I'm sure that with your bigger motor and some of my secrets you should be able to get 85. Post the video to shut up these haterz! :aj:
It was a bit harder for me, and I only managed to hit 82, but I did it on a fully tricked out KDX80. Everyone told me it couldn't be done, but my neighbor is a mechanic and he board it waay out and put 3 powerbands in it. The first time I got it into 6th gear (you might want to look at a KDX tranny to see if you can get an extra gear) and that 3rd powerband kicked in...WHOAA! I about sheet myself! Even then, it was only good for 68. I then found a 18 teeth front sprocket from a street bike. It didn't match the shaft thingie coming out of the engine, but we ground it down some and put the bolt on with superglue. I still only was able to go 76 until I found some of the secrets of weight and wind. I took off the fenders, well, the rear was broken off already, and the crossbar pad, the muffler, the brakes, and the air filter. That got me up to 78. At that speed the awning thing on the front of my helmut was bouncing around alot so I took it off and found it was quieter and could slip through the air faster with the helmut turned backwards and me crouched down real low. Got to be careful crouched down like that, tho, becuase when you hit bumps it can hurt certain parts if your a man, but it can feel good too so it all depends on what you like I guess. With the helmut fixed and me crouched down I was able to hit 79. Then I realized how much all of my clothes weigh and I tried it without them and I got up to 80. I then realized that part of that was because my back was more slippery in the air than my clothes, so I shaved my back, well, I didn't, I had to get my neighbor to help me, he's real friendly, so after that we was finally able to hit 82. We then figgered how much weight we could save by taking the gas tank off so we plumbed up a coke bottle with just enough gas to make one run, kinda like the drag racer guys do. Only problem was the Coke bottle leaked and the gas sprayed all over my parts that I didn't shave and some got on the end of the tailpipe where the muffler wasn't anymore and it caught me on fire. Once I heal up good and the next time my mom's not home, we're gonna try it again, but this type my neighbor said he has a beer can that won't leak like the coke bottle did.
I'm sure that with your bigger motor and some of my secrets you should be able to get 85. Post the video to shut up these haterz! :aj:
Hey Ol'89r,
You must researching information for your Bonnerville attempt, huh.
I think you might just get some good information you can use, here.
Already some good information posted by H.L. Gomer & Dr. Fazz. I know that I am sure fascinated with some of the information I've learned from this thread!
Keep the good sheet coming here! :nod: :cool: :boss:
Your pal, Ken
You must researching information for your Bonnerville attempt, huh.
I think you might just get some good information you can use, here.
Already some good information posted by H.L. Gomer & Dr. Fazz. I know that I am sure fascinated with some of the information I've learned from this thread!
Keep the good sheet coming here! :nod: :cool: :boss:
Your pal, Ken
I don't think low end torque is what is pulling it at 100 mph._JOE_ said:
I think they improved the front fender on the XR650L...speedo said I was going 95-100 and the fender was holding up pretty good._JOE_ said:
Now that I think about it, my XL250 went about 85 top speed (indicated) and the fender was ok. I always wondered why that bike seemed so much stronger than an XR250...maybe the dual carbs had something to do with it.
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- Jan 25, 2000
- 1,822
- 0
Li'L Brian:
It's possible to gear a 250 to top out at 85, but the resistance at 100 mph is too much for 35 horsepower (or maybe 40 horsepower if you're a tuning genius) to over come. You can gear for 100, but, but the 250F won't pull high gear - it will bog down. Even the 85 mph figure is suspect.
As far as putting a speedo on it to prove this - don't bother. You can calibrate any speedo installation to read any thing you want. Example - you can calibrate your speedo setup to read 200, so it doesn't prove a thing. Get a speedo and you'll see what in mean. And don't try the "I paced it with somebody's car, and it said 115 mph", BS either - it's about believable as sasquatch stories. A much more believable and accurate and device would be a GPS (not to mention that it's easier to do). Take video of the GPS.
Although dirt bikes weren't made for top speed runs, even a few of us old guys could be interested in top speeds of dirt bikes. But speed record holders for 250 cc setups have machines that are much lower to the ground and streamlined. Way less air resistance than your dirtbike. And the motors are tuned and geared for that purpose - they would suck as dirt bikes.
If you're serious in your quest for the ultimate top speed for a YZF250, you might have an audience. But don't try and play us...
It's possible to gear a 250 to top out at 85, but the resistance at 100 mph is too much for 35 horsepower (or maybe 40 horsepower if you're a tuning genius) to over come. You can gear for 100, but, but the 250F won't pull high gear - it will bog down. Even the 85 mph figure is suspect.
As far as putting a speedo on it to prove this - don't bother. You can calibrate any speedo installation to read any thing you want. Example - you can calibrate your speedo setup to read 200, so it doesn't prove a thing. Get a speedo and you'll see what in mean. And don't try the "I paced it with somebody's car, and it said 115 mph", BS either - it's about believable as sasquatch stories. A much more believable and accurate and device would be a GPS (not to mention that it's easier to do). Take video of the GPS.
Although dirt bikes weren't made for top speed runs, even a few of us old guys could be interested in top speeds of dirt bikes. But speed record holders for 250 cc setups have machines that are much lower to the ground and streamlined. Way less air resistance than your dirtbike. And the motors are tuned and geared for that purpose - they would suck as dirt bikes.
If you're serious in your quest for the ultimate top speed for a YZF250, you might have an audience. But don't try and play us...
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