From an earlier thread KLX300 or XR250.

Bought the KLX300 yesterday. It's a 1998 that I plan to use as a guest bike until my teenager takes a break from team sports. Probably paid too much but I was far from home and it was cold.

The bike was running when I got there. Never a good sign. The guy said it started on the 4th kick. (yeah, I believed him.

Looked it over, lots of aftermarket stuff:
Pro-Circuit slip on
Uni air filter
Ricochet skid plate
Pro Taper bars
New grips.
Nice Barkbuster style handguards
New Michelin knobby's front and rear.

Bought this bike from a guy that's a mgr. at a Land Rover dealer. They had a remnant of a Land Rover "off road course" on the property.
Took it for a ride, motor pulled strong, was fun to ride. Went through the gears OK but was iffy on the downshift, brakes were iffy, idle iffy, ran and idled rich. (The guy said I rode like a young kid. I'm not and I don't)
I bought the bike.

Got it home, started up on about the 4th kick, idle not very smooth. Played with the idle **** a bit till it stalled, pulled it in the basement.

Wasn't sleepy last night decided to take a look.

So far here's what I found:
Needs rear wheel bearings.
Handful of bolts missing.
Chain is different from KLX250 not sure how to get it apart?
Spark plug was black (rich)
Valves measure .127 & .102 intake - .152 & .152 exhaust. (mm)
Carb had a 132 main screw was out 1.5 turns.

Cleaned air filter.
I replaced the main with a 128 DynoJet main and turned the screw out 2.25 clicks.
I'll put a new plug in.
Not sure about the valves?
They seem to be on the tight end of spec.
But they've probably been there for a long time.
I read Nobrakes post on doing the valves and I think I can get through the process.
Any thoughts on doing the valves before putting it back together?

And Deej, I would post this in the KLX300 forum but nobody goes there. Hope it's OK?

 

Hey congrats on the bike, and sounds like you have a handle on what needs to be done. Don't worry about posting it in here, its the best place to be.

 

You didn't mention the pilot jet size. Bikes around here have a range from stock 35 to 40. I had a 40 and the mixture screw set at 1.5 turns out. But thats at sea level and mostly above 65 degrees year around. YMMV

 

Sounds like fun! Yeah never a good sign when the engine is still hot when you get there. LOL
Dan

 

Didn't check it. Good idea though, I will.

 

It is the best place to be!
Thanks

 

Sounds like a good deal. On the rough idle and richness, I'd suspect that it's been sitting and will need a carb clean...mainly pilot circuit gummed up. That will also give you an opportunity to see how it's jetted. Tranny shifting may be due to needing an oil change. Adjust those valves at first opportunity IMO.

On posting 300 stuff here, the bikes are so almost identical that we just ought to differentiate between street legal and not as far as models go. I call my '06 KLX250S model a KLX300S model now since it has a factory 300 jug on it. I also used an Eibach shock spring for a 300 and Race Tech fork springs for the 300 in my bike...along with the Gold Valve suspension kit from RT for the 300.

 

post it up, congrats on the new toy

 

The valves are in spec. but you might want to open up the tighter intake valve a bit.
Do check the pilot jet. The hole in it is very small and can easily be restricted. Also, shoot some carb cleaner through the fuel port that the pilot jet regulates. The other end is under the throttle plate.

Ride on
Brewster

 

Brewster, thanks for the response.
To open up the tight intake valve, wouldn't I have to re-shim the valve?
And, if I re-shim one, would it make sense to re-shim them all to the middle of the spec?