The bike in stock and mildly modded form won't pull more than 14/42, it just lacks the horsepower to push it along above 70mph without working from 5th to 6th on any incline. I ran 13/42 for 2500 miles and it will get you to your top speed quicker and it will hold it better on an incline. Like Deej said, it revs 500-700 rpm higher in top gear at any given speed. I went back to 14/42 for a while and I think for my 15 mile commute and all the riding I do on and off road I'll go back to 13/42, it's a good compromise ratio.

 

Actually this makes a lot of sense. You need sixth gear to hit the higther speeds but in stock trim, The KLX has trouble hitting top speed in sixth unless you are going slightly down hill. The other thing is the high speed wobble. When you first experience the wobble, it's a bit scary but sliding back on the seat helps a ton. Going bigger on the front sprocket or smaller on the rear sprocket requires more Torque/HP.

 

The klx is not for highway riding at 75-80 mph. It will do it if you want with either the 13 or the 14 tooth sprocket. The rpm's are already high at that point anyway, another 500 isn't going to hurt.

 

In stock form, the KLX is at its peak power around 70-75mph and peak torque around 65-70mph in 6th gear. The KLX is a good commute bike but not a highway cruiser. I find 55-60mph is best cruise speed. Anything more, you are pushing it. A pipe will help open up the top-end and give just those very few ponies needed.

You can alway draft behind a trucker. The KLX really loves it and I can lay off the throttle alot.

 

Where is the best position to be in relation to the truck? Also, How far behind?

 

It depends on how far you are willing to dare. Even just the 2second rule when following really helps, but the turbenlce is sometimes a bit much. I've been less 10ft to a trailer before. Its very scary to be that close, but also distribingly calm also.

 

No, No, No ...... Never draft on a bike.

You want to see the road ahead of ya......imagine a shredded tire on the interstate, do ya think an 18-wheeler will swerve for it, no way, they'll just go straight over and then you got like one milli-second to react....bad idea Never mind a pallet.....you guys need to ride on I-95 in Miami once lol.

 

Hey Gerry did ya get the handguards, were they ok, I told ya they were beat up .... lol

 

off topic but how many links are on your chain? im guessing the stock length eh?

would the 13/42 be the same as a 14/45? and once again im guessing the stock 106 would still work?

 

totally agree with this here. I too did the 13-tooth first mod of all on my '06 KLX250. It really increased my low-end, but at the same time it would send the bike to redline quicker. But, it really didn't increase the 60-mph rpms. It did to an extent, but tbh, not really that noticeable. I then added a new chain and a 45-tooth rear and that really sent the rpms to shock at highway speeds while really not adding that much more low-end. I think the 13/42 is the best for commuting at speeds 55mph and above with a little off-road. But if you're off-road more, the 13/45 is what I'd use as it really pulls the max of the bike's power- it will pull 6th gear redline with 13/42 easily as well. I topped mine out at 95 mph indicated with 13/42 gearing, it was redlining and quite unstable at that speed as well, but it would do it.