Wr250R questions

I just bought a 2018 WR250r. The previous owner removed the air injection system and disconnected the EXUP. Other than this it is stock.

The speedometer reads around 5mph higher than actual however the odometer agrees with the GPS within 1 tenth of a mile on a 10 mile trip. Any way to fix this?

Is the tusk, twin air or HIFO air filters any good for the stock bike? I have belray filter oil.

The bike does not have much power in the low revs. Snapping the throttle open in 1st gear is a bit sluggish until the rpms climb a bit so no power wheelies. Would reconnecting the EXUP help this?

6th gear pulls from 55mph are weak. I find it works best to stay in 5th to accelerate to 65 or 70 than shift to 6th. 70 seems to be pushing it power wise in 6th. Maybe a 46 or 48 tooth rear will help?

When the bike gets in the upper rpms it really comes alive and has a surprising amount of power. It always seem to have a harmonic that sounds like a timing chain rattle that goes away. I made a sound clip of it and it sounds normal compared to other WR videos. The guy had an aluminum skid plate on it however he took it off due to it amplifying the engine noise. Anyway to make it quieter?

I am assuming this engine is designed to be run at the higher rpms for prolonged periods. So will it hurt it to ring it out all the time?

The speedometer reads around 5mph higher than actual however the odometer agrees with the GPS within 1 tenth of a mile on a 10 mile trip. Any way to fix this?
Not really.  There are some aftermarket things that will get your speed right but then your ODO is off.

The bike does not have much power in the low revs. Snapping the throttle open in 1st gear is a bit sluggish until the rpms climb a bit so no power wheelies. Would reconnecting the EXUP help this?
Depending on the type of riding you do you will have different answers on this.  I myself like the EXUP installed on the bike because I have a bit more low RPM torque available when riding slow in tight stuff.
However, probably the biggest change you can make is to get a larger rear sprocket (and longer chain) - I run a 48 tooth rear with a 13 tooth(stock) front sprocket.  Many others will run a 14 tooth front with a 50 or 51 rear.  I believe the ratios work out to be pretty close to the same.

6th gear pulls from 55mph are weak. I find it works best to stay in 5th to accelerate to 65 or 70 than shift to 6th. 70 seems to be pushing it power wise in 6th. Maybe a 46 or 48 tooth rear will help?
If you still have the stock gearing(see above) this is pretty normal.  Change the sprockets and things will be a bit more lively

When the bike gets in the upper rpms it really comes alive and has a surprising amount of power. It always seem to have a harmonic that sounds like a timing chain rattle that goes away. I made a sound clip of it and it sounds normal compared to other WR videos. The guy had an aluminum skid plate on it however he took it off due to it amplifying the engine noise. Anyway to make it quieter?
Sounds like my bike.  You could always get some sound deadening material for the AL skid plate, go to a composite skid plate, or wear ear plugs.

I am assuming this engine is designed to be run at the higher rpms for prolonged periods. So will it hurt it to ring it out all the time?
18,000 miles on mine with quite a bit of Interstate and Highway miles and along the way some time spent on the bottom of some water hazards - still runs great

Thank you! My bike has 6800 miles on it. The previous owner used it as a daily commuter bike.


Any recommendations on sprocket brand? I have read some aftermarket sprockets can eat up the counter shaft splines.

Well for the front sprocket I pretty much just is the OEM part. However that won’t help you if you want to go with a 14 tooth front.

For the rear I typically run Primary Drive brand from RMATV. I usually order the steel ones.. actually I am on the same steel one that I ordered 14,000 miles ago.

Normally the front wears out first so I keep an eye on it.