wr250r gearing sprockets for top speed.

Okay everybody, I hope Im not the only guy who is wondering if anyone has changed the stock sprockets on their wr250r 08' or 09' model - to get more top speed out of it and to run high speed with lower R.P.M.s too. I know that there has to be someone else out there too with these riding preferences or desires and I am wondering if a person went from the stock gearing to 3+ teeth up on the front sprocket and 4 or so teeth down on the rear sprocket if the wr250r would pull past the average bone stock top speed I keep hearing which is around 85 M.P.H. I have heard some say that it doesn't have enough power to pull these kind of gear ratios to reach higher speeds such as a desired 90 maybe even 95+ mph. I would like to think it could pull high speeds of 90 - 95 if the sprockets were geared up high enough, So does anyone know if this is possible to increase the top speed signifigantly with uping the sprocket gear ratio and WITHOUT modifying anything else on the bike??? P.S. remember this is a WR250R 08 or 09 model, and I just want to get the highest top speed possible out of it gearing wise, nevermind low end, torque, or why, it is just a preference of mine, and I also MAINLY ride out in wide open areas.

I will start by saying that the stock gearing is set by the factory to get the most usable power out of the motor. By changing your sprockets that much to get higher speeds would make the bike unusable for trail riding at the average pace.

The issue your will have is that WR250F motor is not designed to run at 80-90 mph for long periods of time. If you are needing to go that fast, you should be looking into an XR650 or a KTM 530 xc-w

Ahhhh, he's asking about a WR250R not a WR250F. You(the poster) need to ask this question in the Yam dual sport forum, thats where you will find WR250R info. The R and the F are like comparing apples to dump trucks.

This is the weirdest question I've read so far. Ive never heard someone talk about increasing 3-teeth on the front sprocket in my life.(no offense)

This bike will do nearly 100MPH in stock trim. Adding 3-4 teeth to the front and removing 3 or so from the back would get you 150MPH or more!? Of course the low 20- something horsepower of the motor would never get you that. IMO the bike would be un- rideable with that gearing. You might want to try only 1- tooth to the front sprocket or 2 or so less on the rear at a time.

If you havent already purchased this bike, Id seriously consider searching for a different model.

i have the same bike so i understand what you are saying, i own the 2009 model and i thought about switching out the sprokets also but this is what i came to notice-

regular yamaha 250 bikes like yz250f or hondas like crf250's are geared around 12 in the front and 48 in the back which is good for bottom end/snappyness and found it interesting we are geared 13 in the front and 42! in the back so we are already geared realllly high already which is taking already alot of power from the bottom end performance but its "dual sport" so it is geared like that for road cruising...

(if you didnt know adding 1 tooth on the front is like taking 3 OFF the rear, so adding 3 in the front would be like getting a 33 spoke rear which would be literally imposible to drive under like 15 miles an hour and not ruining our clutchs)

but what i am going to do is get a 14 teeth front sproket and see how my bike reacts and i think you should too, if it doesnt seem to affect my bottom end in a unreasonable way then they sell a 40 teeth rear sproket that they sell for our bikes so basically with both those sprockets would add up to like taking 5 teeth off the rear which in reality SHOULD give us a top end around 100mph if the engine agrees with the gearing (which it should) and will give us the ability to cruise around 75 at the bottom of 6th which is probably the main thing your looking for just like me

like i said though you would be sacrificing serious bottom end, you would have alot of trouble going under 10 mph like turning around and trails but you seem to be aware of this

so hopfully the novel i have writing you have been any help coming from some one in the same position and by the way they sell both those sprockets for reasonable prices on ebay

-dustin

just read up a 14t doesnt seem to affect bottom end but improves top end making top speed around 95, 5th gear goes to 93 and 6th gives you the extra 2 mph, but make a huge differnce on the cruising trips on the bike

well we here in oz on a WR 250 07 model are running em motard set ups on road and tracks

im currently running up to a 15 front and 14 fronts with out a problem

renthal sprockets are the only one makeing a 15T

rears we run any thing from 45 to 44 to 42 right down to a 38 if need be

and yes the WR pulls this gearing just fine

dont belive a thing people say

you can gear em and we do

dont under rate your WR guys think out side the box and the book

i can hit speeds down a strait with my WR 250 about 140ish easy with a 15/low rear we do it every week end

www.vsmr.net

sick i didnt know that, buttt a 15 wont fit on the wr250r what mods did you do to change this? because a 14t barely fits and has to make self clearence once you ride it

sick i didnt know that, buttt a 15 wont fit on the wr250r what mods did you do to change this? because a 14t barely fits and has to make self clearence once you ride it

sorry its not 250R enduro WR 250 07

soz i shouldent of posted that here

but hey dudes look with WR's anyway

Does anyone know where to get an steel 48 tooth rear sproket and a 12 tooth front sprocket for the wrr?? i can only find aluminum and i dont care for aluminum

ya aluminum sucks, i would check ebay honestly

Does anyone know where to get an steel 48 tooth rear sproket and a 12 tooth front sprocket for the wrr?? i can only find aluminum and i dont care for aluminum

WWW.sidewindersprockets.com

I am going to go from a 13/43 stock on my wrr to a 14/42 to not go too tall, what you think? sorry I didnt respond sooner. Mike :-) I hope I can cruise at 75mph with out winding out soo bad and hopefully it will fix my exaggerated 5 mph off speedo too. 65 indicated is actually 60 right now with stock gearing, what you think on that too please? My top actual speed right now was clocked at 85mph, and I weigh 205lbs, not bad, but wonder if I can squeeze more than that after I get the 14/42 gearing on it, or at least stay the same and cruise with lower Rs I hope!

i have the same bike so i understand what you are saying, i own the 2009 model and i thought about switching out the sprokets also but this is what i came to notice-

regular yamaha 250 bikes like yz250f or hondas like crf250's are geared around 12 in the front and 48 in the back which is good for bottom end/snappyness and found it interesting we are geared 13 in the front and 42! in the back so we are already geared realllly high already which is taking already alot of power from the bottom end performance but its "dual sport" so it is geared like that for road cruising...

(if you didnt know adding 1 tooth on the front is like taking 3 OFF the rear, so adding 3 in the front would be like getting a 33 spoke rear which would be literally imposible to drive under like 15 miles an hour and not ruining our clutchs)

but what i am going to do is get a 14 teeth front sproket and see how my bike reacts and i think you should too, if it doesnt seem to affect my bottom end in a unreasonable way then they sell a 40 teeth rear sproket that they sell for our bikes so basically with both those sprockets would add up to like taking 5 teeth off the rear which in reality SHOULD give us a top end around 100mph if the engine agrees with the gearing (which it should) and will give us the ability to cruise around 75 at the bottom of 6th which is probably the main thing your looking for just like me

like i said though you would be sacrificing serious bottom end, you would have alot of trouble going under 10 mph like turning around and trails but you seem to be aware of this

so hopfully the novel i have writing you have been any help coming from some one in the same position and by the way they sell both those sprockets for reasonable prices on ebay

-dustin

at 75 mph 6 gear is around 8k rpm's, The bike is right in the powerband and has major trouble pushing the bike any faster. you hit 85mph and cant go faster and at 85 in 6th your at about 9k rpm's which is where max hp and torque is acheaved gearing the bike up will not help.

With the stock gearing the bike can reach 105-108 mph but does not have the power to push it. If you spread the gearing out more with a 14/42 6 gear probly wont have the tourque to push 75, it barely does with 13/43. I would not recomend gearing up. you will end up being in 5 gear to reach 75 which will defeat the purpose.

Hey go for it anyways a front sproket is like $10-15 try that first before droping the rear. You will get better gas mileage cause you will be at a lower rpm at any given speed/gear

If you want to reach your goal you need to mod your bike. Get a fuel programmer, mod the airbox and get an aftermarket can or de-cat/baffel the stock can. With the extra 4 hp or so id bet you could gear up and get what you want.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now