So last time I rode i noticed a change in engine sound near the the end of the ride. The idle was also hanging a bit when i would let off the throtle. Put the bike away till this week. It started on first kick then died. Started on 2nd kick but you could tell something was going on and then died. No more starting! Changed the plug and started 1st kick.

This has happened to me 4 times in the last year and I doubt i i've put over 300 km on the bike in that year. What else could cause plugs to suddenly crap out (other than rich jetting)?

I also got a crap load of jets in the mail the other day. Every main between 165 and 185 plus a 40 pj. After changing the plug I tried the 165 main (from the previous 145) and noticed that the bike could easily lift the front Wheel at low RPM's compared to before. This was only a short test around my house with a cold engine but I liked the feeling and am looking forward to trying it out in a full ride.

I had a racebike with a marginal ignition that used to eat plugs.
I grafted on a cr ignition and problem went away. Coil and plug cap might be a good start.

Some 2t oils are worse for leaving residue on plug...and vary on spooge produced

I use Amsoil interceptor.

The only change that happened not too long before plugs stated fouling was the installation of an aftermarket voltage regulator.

I?ll be doing a test with the new jetting soon

Thanks for bringing that up. It has been simmering for a while but i'm gonna look into the ignition coil. I looked at the coils on my kids bikes (kx65 and 85) and both fit onto the gasser. Both have big bike plugs in them (br9ix and br10eg) so would I be wrong in thinking they should work on my bike if I want to do some testing?

I recently unpluged my voltage regulator as that was the last change I had done to the bike before it started fouling plugs. Fouled a new plug within a 1hr ride anyways.

Today I cleaned up the power valve as it was sticking a bit, i doubt it wil change the fouling plugs but i'm looking forward to see how the power will be affected. I want to change things by process of elimination so that know exactly what is wrong. Next up on the list is checking/replacing the reeds and changing the needle as someone had pointed out that it might be worn out. I also realized the gap on the plugs I have been buying from my local Honda dealer was way too small so I will now be keeping a eye on that and setting to the right spec (0.6).

I dont think my rh crank seal is leaking because the trans oil stays clean and the level doesn't budge.

I dont get much riding done these days for one because of the long winters and I just got back from 2 months in Latvia. I know riding with my kids at lower speeds might be one of the causes for fouling plugs and that just riding faster and at higher rpm might fix it, but I still need to figure out why plugs are sudenly craping out on me.

Any other ideas?

Ign coil from kx will work fine complete with cap.

After that the stators don't last forever and can fail slowly and are hard to test definitively. See other current threads on stators.

If using Motul 800 it can foul by slow riding.
Are you still using the 40 pilot jet?
What ratio of fuel to oil mix are you using?
How many hours on the bike? Maybe replace the exhaust packing as well?

Isn't this a Lean condition?

Can?t remember if I actually put the 40 in there. But yeah I?m also thinking I?m a bit lean compared to every ones jetting recomamdations. I?m running intersepror at 50:1 and I don?t know how many hours it has but I did do the packing a while ago. It might have 15-20 hours on the packing.

Are you sure that's a genuine Keihin Main Jet?

Are you sure it's a genuine Keihin PWK38 carb?

Sorry, I don't mean to sound rude, but there's a lot of fake Keihin PWK carbs on the market.

145 Main Jet sounds very lean at WOT, I mean dangerously lean. :eek:

All the best, Dave.

The main is now a 165 that I bought from Rocky Mountain.

And I can?t be sure it?s a genuine keihn carb because it?s what was on there when I got it. But i doubt it?s a fake. Previous owners were not the kind of people who cheaped out.