if you do any high speed highway riding...the 15t is a no brainer....i'm thinking about going up one teeth in the rear to a 40t...need just a tiny bit of umph....any thoughts?..seems like a problem will be finding a 40t rear sprocket for the klx....

 

My cold start procedure is that I'll crank whilst pulling out the choke. When it starts, I release the choke instantly so the rpm doesn't go to 3000rpm with no oil circulating. It will then idle gingerly at 1200rpm while I put on my helmet & gloves; hop on, ride off, no stalling or flat spots. Hot start, I roll the throttle slightly whilst cranking & she fires up straight away.

I suspect that your carbs pilot circuit maybe lean. Readjust your mixture screw or increase your pilot jet size.

Good feedback. I think this will be my next mod. What sort of difference did it make to engine rpm when cruising... say 90 km/hr (55mph)?

 

14t
6k RPM = 90km/h indicated
7k RPM = 104km/h indicated

15t
~5250 RPM = 90km/h indicated
6k RPM = 99km/h indicated
7k RPM = 107km/h indicated

Going from memory...

I pulled all the way up to 145km/h today, barely touched it... but it got there, and with room to go still, I think with an aftermarket pipe it would hit 150km/h. That was very calm wind at the time.

It's nice though, 5th gear is essentially where 6th used to be... about 2-3km/h slower. So you can rev the **** out of it till you reach the speed you want, then drop the RPM by about 800-900 RPM and be a bit more comfortable.

I rode my buddies DRZ400SM tonight, first time on a bigger bike aside from a cruiser... that thing blows the doors of the little 250 Hah. I hope someone buys my KLX soon Maybe I should post it up for sale here. I plan on getting a DRZ for sure now after riding my friends.

 

I tried your cold start method, of pressing the starter while pulling the choke out, once it fired I pushed the choke back in, and it idled a bit low at about 1000rpm, then sped up to the normal 1300rpm I have it set at.

Put my helmet and gloves on, and rode off smoothly.

I've been doing it wrong, and wasting precious fuel all this time!

I really doubt this method will work when it's cold out though, I have to choke the bike for a few minutes in the cold till I can even get it to idle, and then I can't barely drive it away or it bogs like crazy. I'm talking near/below freezing temperatures, not 10c like some people in California might run from.

 

Glad to hear you had a win of sorts. It doesn't get that cold in Perth, West Aust. A cold morning for us would be 5 deg C.

In regard to the 15T gear; how is it off the mark? Do you have to rev a bit more/slip the clutch when taking off from a standing start? How is it off road in sand/climbing hills? Thanks

 

I ride an SF, it doesn't see trails.

I apparently know how to launch quite well...

A big dirty Harley with straight pipes, 2 supersport bikes, a DRZ400SM, and me... all launched it off a red light last night... I was first across the intersection... with the Harley about half a bike length behind, the DRZ the same, and I don't think the sport bikes were ready for the 3 of us to launch, but either way I beat them all Haha.

If you want to take off slow... yeah it's a bit more choppy feeling as the tractor gets up to speed, need more clutch slipping.

Yesterday was far less windy in the evening, and the bike can still pull up medium/small hills in 6th, there is one big huge long hill I regularly ride up every weekend or two, and I could maintain speed, but not accelerate past 100km/h up it. I dropped a gear and easily got up to 115km/h up it.

 

I installed a 15T CS sprocket yesterday & here are my impressions. It's a compromise but overall I'm happy that it now has longer legs. The OP mentioned it's like have an extra gear which is a good description. A downside is that it doesn't like crawling around in first gear @ idle like it use to with the 14T gear. I'll take it out on a rocky trail next weekend to see what affect it has down low.

 

your pilot jet is either partially blocked or your fuel screw is set too lean, maybe both


one way to verify your front sprocket is the right fitment for klx250s is to cross reference it to a Lakota300 or Mohavie250 atv. They use the same sprocket.

Only mention it because some places will try and give you a klx300 sprocket which is not the same.

 

"I could maintain speed, but not accelerate past 100km/h up it. I dropped a gear and easily got up to 115km/h up it."
Haha, you have discovered the paradox of taller gearing on the KLX: you end up with a lower top speed in top gear! I run a 13t front sprocket and I was shocked to find that I GAINED top speed (~10kmh) in 6th gear!

 

for me, it wasn't about the top speed...it was about the top cruising speed...with the 15t front, on the flat or going up hill, i can't redline at wot on 5th or 6th gear....only way i can redline is if i'm going downhill......but, i can cruise at 80 +/- mph all day long on the flat endless desert highways...and, cruise up mountains for hour at 75 mph max on 5th all the way to the top...

i also have the 13t...it's fun for the city, but there is no way i can commute on the highway with the 13t front....even the stock 14t front, rpm were bit too high for everyday highway commuting....