Simple Valve Question + wondering

Can valves that need adjusting foul your plugs so quickly that you require new plugs within 10 miles?

I haven't had the time to start tearing stuff down this past month, and am just looking for a place to start.

I have new carbs from WG on the bike. When I put new plugs in the bike starts with one kick. Then after a while it just starts running crappy (after a fwe runs up and down the steet) then out of nowhere it starts to lose power and shudder and then everntually cuts out and won't start again until I swap out for new plugs. The ones that come out are completely carbon fouled. Execept fro one cylinder that doesn't seem too bad.

When it runs I get a little smoke from the left pipe. Well, a little more than the right at least which is wat I would consider just a nrmal exhaust on a bike this old.

I also have thecoil mod done on this bike. I wonder if I should start looking elecrical or mechanical for the probem?

Post edited by: MattBlack, at: 2006/07/17 13:11

Check compression and do a leakdown test.
Valve seals?

Post edited by: hwms, at: 2006/07/17 14:31

I have the same problem on my bike. It's probably a low compression thing.

donthekawguy wrote:

I have the same problem on my bike. It's probably a low compression thing.

Well I tell ya what.... the first person to figure it out, let the other guy know.

Sooty plugs can be caused by a number of things. They are a sign of incomplete combustion.

An obvious cause would be the wrong air/fuel mixture with the fuel component greatly out of whack. This means that the carburetors are greatly over-jetted OR air is obstructed as in dirty air filter(s).

Another source of incomplete combustion is poor compression. Many cases of poor compression are the result of lack of valve clearance. See the write up on my web site. When a valve lacks clearance, the valve tends to hang open and compression decreases and this causes very poor combustion and sooty plugs. There are other sources for low compression but checking valve clearances is about the only one that can be done without disassembling the engine.

A third source of incomplete combustion is poor spark. There are MANY reasons why spark can be poor. Timing, points that need gapped or are worn and bad condensors... plug wires/caps/worn plugs as well as coils that have resistance that has increased over the years or are shorting. The MAIN source if everything in the ignition seems good is just poor voltage at the coils. Have you checked the voltage going to your coils? See the FILEBASE and look for the Coil Powering article I wrote.

If you are only going 10 miles and fouling plugs, the problem should be VERY easy to find especially if you look at the things I point out.

Post edited by: wiredgeorge, at: 2006/07/18 08:56

Hey it only took me two years to figure out my problem. I guess I was avoiding the obvious.