Triumphrat

ontopcop

My '03 Speedmaster has 19k miles. Up keep on maintaience, oil changes etc are up to par. All of a sudden she started running like she was starved for gas. Kinda like the first time you forgot to turn the gas on and you started stalling out! Then she will start to run a bit and then hesitate some more but at no consistancy. She warms up fine, then once warm and running she starts stalling. I drained the tank and checked the petcock screen, it was a bit dirty with some debree, but bottom line, this didnt fix the problem.

A mechanic told me it would be one of four things,

1. Water in the tank or carbs. Drain gas etc. Well, I know its not that.
2. coils $ ?. How do I check to see if the coil is bad?
3. Crank trigger $70.00. How would I check this?
4. Ignitor $500.00! Ouch. How would I check this?

Obviuosly I am going to go ahead and start with replacing the coil(s), I hope my haynes manual covers this, as well as the other possibilities, its not with me at the time.
Has anyone had any similiar problems? Or have any idea how to figure out which one it is, so I can go right to the fix.
Thanks

Lanny

singring

I would guess your tip-over valve is clogged. Follow your fuel tank vent line to the black plastic tip-over valve. Remove the valve, and spray some DRY lubricant, then shack it up and down til you hear the valve open and close. Before you return the tip-over valve to the vent line, try running your bike, and see if it cuts out. If the bike runs fine, then you know the tip-over valve was the culprit.
Another, thing to check is the 4 vacuum caps on the manifolds....even the tiniest crack will allow air into the system. Replace the caps, and use small hose clamps to secure them.

JohnB

Lanny,

I had a similar condition on an old BMW. It was suffering from the hairline crack syndrome. Once the bike warmed up, the coil started to discharge itself onto the GAS tank But before you replace anything, you really should test it. The Haynes manual will guide you, all you need is a cheap multimeter from Radio Shack or Sears. I'd also warm up the coil with a hairdryer to see if that has any effect on internal resistances.

I'd also check your air and fuel filters. A clogged up air filter will make the bike run a little rich, not a big deal when cold, but will become noticable when warm.

The crank sensor is easy to check. Just measure the resistance using your multimeter, and compare with specs in the manual. BTW BMW wanted $600 for my old R65. Fortunately I found a retired elec. engineer who rebuilt mine for $120.

The ignitor may not be so easy. Back in the 80s, a few simple resistance measurements would tip you off, but todays ignitors are too complex for this approach. The dealership may have a scan tool to help you out, or you might be able to find another America rider in your locality who will let you borrow theirs for a few minutes to see if that helps.

I'd also also check your gas tank vent. Run the engine until she starts to stumble, then open your gas tank cap. If you hear air rushing into the tank and/or the bike starts to run well again, your vent line is probably clogged.

These intermittant problems are most fustrating. Take your time, you'll eventually figure it out. When you get really PO, take a break. Kicking the bike will not help ... I've tried this approach and it doesn't work!

Good luck with it
JohnB