My '07 2.9 has been fouling plugs as of late, generally after about 4 hours of riding. When I pull the plug it is black and sooty. However the bike runs fine for several hours, it doesn't act blubbery, actually pings a little at about 1/4 throttle. I am running v force reeds and 36 on the pilot and 120 on the main. I tried leaning it out on the clip, but it runs too lean then. I have a feeling my silencer is loaded up with goo. Could this cause the plug fouling condition? And if so, how would I go about cleaning out the silencer? It was suggested to me to go out and run a bunch of hill climbs, but where I ride there's not much in the way of big long hills. I tried the iridium plug also with the same results. Running a BP5ES right now. Any ideas?????

make sure you are using the exact plug specified and then clean out the muffler.

Wot gas and oil you running?

Never really had that problem, but? I can tell you how to clean the muff, if you are lucky and not running the wrong stuff!

My '07 2.9 has been fouling plugs as of late, generally after about 4 hours of riding. When I pull the plug it is black and sooty. However the bike runs fine for several hours, it doesn't act blubbery, actually pings a little at about 1/4 throttle. I am running v force reeds and 36 on the pilot and 120 on the main. I tried leaning it out on the clip, but it runs too lean then. I have a feeling my silencer is loaded up with goo. Could this cause the plug fouling condition? And if so, how would I go about cleaning out the silencer? It was suggested to me to go out and run a bunch of hill climbs, but where I ride there's not much in the way of big long hills. I tried the iridium plug also with the same results. Running a BP5ES right now. Any ideas?????

try running 98 octane petrol i had exactly the same problem on my cr250 i changed to 98 octane and not had a bit of bother since

Running 93 octane BP fuel and elf 2 stroke oil, 80:1. Funny thing is, the bike never fouled a plug for the first 6 months running the same setup.

Running 93 octane BP fuel and elf 2 stroke oil, 80:1. Funny thing is, the bike never fouled a plug for the first 6 months running the same setup.

My dads 02 sherco 290 is ran at 70:1.

Edited August 3, 200719 yr by honda_tlr

Most Shercos carry a sticker stating that 98 RON fuel should be used.

The 93 pump gas should be fine in the later models. Never tried the ELF stuff, but I think it is a full synthetic so should be ok. Maybe you are on to something with the muffler thing.

If you can't get a good hillclimb going, surely you can find a place to blow it out on a scrambles track somewhere. Usually after 5 minutes of good hard running they ars smoking like a freight train from all the old oil in the pipe.

I'll send you some other info via e-mail.

ps- guess you ruined that expensive plug I sent you?

MC

I would try cleaning those expensive plugs in a proper plug cleaner or bead blaster before chunking them. You may be able to save them, never know!

Sent you the stuff, not to be shared! Sorry! You are a certified test pilot now!