MK3 quits when warm

Commando Cam said:

I have a MK111 and a Trident, and fwiw in my experience the cause is almost always the simplest root cause. I've experienced a blocked tank vent as has been suggested by several others and it behaved exactly as you have described. the thing that threw me off was the motor would die at varying times. That turned out to be caused by the amount of gas in the tank. Just pop the tank top and start her up. If she doesn't die in 10 minutes, you're healed. I also agree with some electrical contact cleanr in the stop switch. In any even, don't go pulling ignition systems till the easy stuff is eliminated. If you'll indulge me, I'll tell you a true story that illustrates how we can make things more complicated than they are.
About 15 years ago I was walking down Monument Ave in Richmond, VA, when I came upon a young man with a new honda. He had the tank off, the seat, timing covers, plugs, valve covers, carbs half apart and battery out all off and spread out all over the place. He had a work shop manual out and half the bike spread out on the sidewalk. I stopped and mentioned that I knew a little something about motorcycles and asked what the problem was. He said "the bike won't fire. she turns over but no fire". "I traced the electrical system and I have spark , but the plugs are dry". It was then that I noticed that the bike had 30 day temporary tags (brand new bike, brand new rider). I looked down at my feet and saw the gas tank. I bent down and picked it up and gave the tank a shake. Bone freaking dry, I mean not even a drop of fuel. The young riders face became red as realization hit home. I smiled and told him I was happy to be of service and to not be too hard on himself.
Cameron
'75 mk111 850 roadster
'74 T150V Trident

Click to expand...

stang484 said:

Old Brit sells one that replaces everything from pickup to spark plugs kinda pricey but works good and has a selectable advance curve just don't try to start it on the "aggresive" curve if you don't want to look down on your bike from way up.

Click to expand...

Norton-Villier said:

It woudnt hert to clean the kill switch. What ever you do do them one at a time so you know what the problum was. Unless you dont care

Phil

Click to expand...

Mark said:

The problem is definitely electrical, not fuel related.

Click to expand...

Mark said:

stang484 said:

Old Brit sells one that replaces everything from pickup to spark plugs kinda pricey but works good and has a selectable advance curve just don't try to start it on the "aggresive" curve if you don't want to look down on your bike from way up.

Click to expand...

I really have no Idea what that post means, but thanks for trying to help.

Click to expand...

swooshdave said:

Mark said:

The problem is definitely electrical, not fuel related.

Click to expand...

Famous last words. :mrgreen:

Click to expand...