Bonneville America Forums Forums Technical Forums General Tech Cutting out

My 02 TBA is cutting out at highway speeds. This started in the fall and suddenly the plugs started fouling which they had not done before. Today I took it out for a test ride after doing the following things: Took out little gas filter and put in an inline. Gas tank is venting well. New plugs. New jets (too small actually). Float height is good. New battery. K&N air filters are clean. The problem still exists. I can red line it in the lower gears with no problem but once I hit 4th and try to open it up the problem starts. It also seems to be heat related. Could it be electrical? I'M hoping someone could help me figure this out. I'll be back on this site at 10PM tonight to answer any questions. Thank you.

I forgot to mention that the gas is new & clean. The bike had not been sitting around unridden. It has 48,000 miles on it. Freak, Bubs, 145 mains, 42 pilots, 3 1/2 turns on pilot screws and I'm at sea level. The bike ran great all summer and this problem just hit.

Check ALL electrical connections and apply dielectric grease to them all after you take them all apart.

My 02 america is doing the same thing,Does anyone have advise or the solution?

Call the mechanic at dealer and see if there is a problem with the ignitor going out at this mileage or how to ohm check it or the coils.

I've ohm tested and it seems fine but I've ordered a new ingnition sensor any way.(also called a pick up coil or ignitor). Coils have been tested down at Daytona by a dealer and checked out OK but I couldn"t leave the bike for him to work on it long enough to find the problem. All electrical connections are good and are greased with dialectric grease. Someone suggested a possible short in a wire but I can't find one. I just hope it's not the ignition controll unit. $500 for a new one and no way to test the old without swaping it out. If the ignition sensor doesn't fix it i'll be trailering 250 miles to the dealer. We need a Triumph dealer in northern N.Y.

When the bike is cutting out, is it both cylinders equally or does one side cut out more than the other? If one is cutting out more than the other, you can swap the left and right coils. If the same side still cuts out more, then the coils are eliminated and it's probablly the igniter (CDI).

Both sides foul exactly the same

I don't know if this is normal or not but today I hit the rev limiter hard and had to shut the key off to reset it and restart the bike. I didn't even stop the bike just died and I hit the kill switch didn't work then hit the key and it fired right up and ran fine.

do they foul the plugs? Or electronicly cut out?

The plugs foul. very sooty after a few feet down the road. It seems to be electrical because it has progressivly gotten worse, even if I put in new plugs. At first it was cutting out at highway speeds and then recovering itself. Now I can't go 100 yds without it stalling. It fires right back up with a big backfire, goes 100 yds and stalls again. It idles fine, no problem when I rev it, but under load it dies. I know it sounds like coils but they checked out ok at the dealer. My gas/air set up is the same as I've always had it with no problems.

Any chance it's a faulty choke, or plugged air filter?

and that cured it? I never had that happen before where it totally shut down.

Yep. That cured it. Went back to working like a normal rev limiter after unpluging the tps.

Why do these bikes even have throttle position sensors? I thought the purpose of a TPS was to malfunction in a late model GM vehicle causing all variety of difficult to diagnose performance foibles Seriously though, what is the point in a non-EFI system?