94 XR250L running lean

[runmikeyrun]

Hey guys,

I'm leaving on a road trip on my XR next week and while doing some maintenance I went to change the plug and found this:

What you can't see in the pic is the tiny white balls on the end of the electrode. So i know it's running lean... I thought i heard it pinging last week during an enduro when I had it WOT in 5 and 6 gear on the road sections.

A couple thoughts, let me know if you think i'm on the right track:

-I cleaned and re-oiled the air filter about 300 miles ago. The first time I over oiled it and it wouldn't start. I cleaned it and oiled again, just spraying the filter once over with the oil, then massaged it in. Could i have under oiled it and it's now getting too much air?

-I haven't had the valves adjusted in oh, 4000 miles :/ I don't know how to do it and haven't had the money to pay a shop. It doesnt tick and starts easily and runs good- no pops or backfires. My bike only has 7,000 miles on it and I maintain it pretty meticulously (except for the valves) and don't beat the crap out of it.

-one of the exhaust flange nuts was a little loose, but I don't think it could suck air in through there. All the bolts and clamps on the intake side were good.

I don't want to take it on the road trip and have a piston melt... i'll be doing sustained 55mph on most of the back roads. It doesn't pop on decel, which is why I didn't think it was running lean to begin with, and like I said it starts easily and runs strong. I always run premium fuel. Where should I start? I replaced the plug already.

Thanks in advance.

[Trailryder42]

I would get to where you oil your filter the same way consistently every time and tune the bike for that.

For your sustained high speeds and given what that plug looked like, I think I'd drop in a richer main jet.

Don't let doing the valve clearances scare you. It's an easy job and it needs to be done. You just need some basic tools. Surely you know some other riders in Ohio that can help you. The guys here can walk you thru it too.

Make sure you're running the proper plug(heat range).

[runmikeyrun]

I'm running an NGK DRP8Z plug which i believe is correct. I think i'm going to give the air filter a little extra oil and see how it runs. As for the valves I'll see what I can do before the trip.

Thanks,

Mike

[ramz]

i'll be doing sustained 55mph on most of the back roads.

The Honda Service Manual calls for DPR9Z for extended high-speed riding.

I suggest you put one size larger main jet in. And/or shim the needle with a thin washer.

[Trailryder42]

The Honda Service Manual calls for DPR9Z for extended high-speed riding.

I suggest you put one size larger main jet in. And/or shim the needle with a thin washer.

There you go. For the sustained high speed riding you're doing you're running too hot a plug. The -9 is a cooler plug, so try that along with the main change.

[runmikeyrun]

There you go. For the sustained high speed riding you're doing you're running too hot a plug. The -9 is a cooler plug, so try that along with the main change.

Ok awesome, thanks guys! I'll pick one up. I also picked up some octane booster to help.

[Trailryder42]

I'll pick one up. I also picked up some octane booster to help.

Don't just buy one. Always have a spare.

If you've been running premium gas, octane is not your problem. The Octane Booster is a waste of money. I doubt you'd have bought it if you were aware of how much it actually boosts octane. For example: if the bottle says it boosts up to 4 points and you add it to premium 91 octane pump gas, it raises octane to 91.4. Not worth the cost of the stuff.

[runmikeyrun]

well that's irritating! grrr... thanks for the heads up I guess i will pitch it. And yes I should have noted that. I always buy two plugs, one for the bike, one for the tool kit.