Bike is a 2006 klx250s with 9000 miles.

About 4 weeks ago, I went on a pretty hard offroad ride and spent about 20 minutes talking in a parking lot after. When I got on my bike, it started right up and idled fine. When I let the clutch off, it died immediately. I reved it around the parking lot and eventually, I was able to take off and ride home. I chalked it up to the engine being a little cold.

This past weekend, I was trail riding with my camping gear(extra weight which made things harder) and the stopped the bike to help a kid stranded on the trail with a bike that wouldn't start. Hopped back onto my bike and the same problem happened. It started right up, no choke, idled fine, reved fine and I could move the bike by slipping the clutch but the soon as I let the clutch out completely and the engine was under 100% load, the bike died immediate. I could move the bike by slipping the clutch. I let it warm up for a bit, no luck. Drained the bowl, no luck. Reved it around while slipping the clutch and I was able to ride as if nothing was wrong.

Parked the bike for 10 or 15 minutes at the parking lot only to have the same symtoms when I tried riding away. Eventually, it comes around and I am able to ride. On a whim, when I got home today after a long (12 hr) ride. I parked the bike and tried to recreate the symptoms but the bike started right up and ran fine at both the 10 minute mark and the 30 minute mark.

I am at a loss for what to do next although I do think it is fuel related because I had a lean backfire while trying to get it running after being in the parking lot today.

I can move the bike if I slip the clutch, the moment I put the engine under load with no clutch engagement, the engine dies immediately.

My side stand and clutch safety switch are bypassed. I pulled the carb and everything looks fine although I did blow everything out to be sure. Valves were checked at 6500 miles.

Maybe a vacuum leak? Could something in the clutch assembly be at play?

I don't want to overlook something and end up stranded.

Thanks for any advice.

 

O_o ghost, buy a new klx

 

What was the air temp? was it below 8 deg C, I'm thinking carb icing

 

Hi, to me it seems like a problem with one of those switches, maybe you should double check that?

 

I,ve had best luck with simple fixes first.Try a new plug even if plug is fairly new.

 

Clean or replace your fuel filter, sounds like something is restricting the fuel flow from the tank to the carb.

 

I'd be going back and re-checking the safety switch bypasses, particularly the side stand safety switch. A dump or riding rough terrain may have jiggled a connection apart, or close to apart, something not really visible.

For those that aren't up to speed on what the safety switches do....

The clutch safety switch basically acts as a starter interrupt. If there isn't a complete circuit in the clutch safety switch system, the starter won't engage.

The side stand switch acts as an ignition interrupt. If there isn't a complete circuit in the side stand switch, the bike will cut out when the clutch is engaged when in gear. The bike will start and run, but you will lose power to the plug when you engage the clutch while in gear if the switch indicates the side stand is down. A loose or corroded bypass connection MIGHT produce the symptoms described.

Let me be the first to say internet diagnostics can be harder than Chinese arithmetic. It's probably a lot like having snail mail letter sex....without the benefit of seeing, hearing, touching, smelling and sometimes licking the subject of your attentions, it can be hard to make the right next move.

 

Quoted for the genius analogy.