Triumphrat

Indypsychobilly · 08-23-2006

I posted this on the cafe corner, but thought i would post it here as well to see if i get some more ideas. here's the scoop.

i bought a used '04 thruxton a little over a year ago. i had absolutely no problems at all with it until this spring. it has D&D mufflers and A.I. removed.

the start of the problem began one morning on my way to work. i started the bike and let it idle while i was putting on my helmet etc. i rode about one and a half blocks and it died. it wouldn't start for the longest time, not even a sputter. finally after trying to start it for about 5 minutes, it fired up and ran fine.
i thought maybe i was lower on gas than what i thought so i rode imediately to the gas station and filled it up. when i tried to start it to leave the station, it wouldn't start again. each time of trying to start it after it died, it acted like it wasn't getting either spark or fuel. not so much as even a burble or backfire. i pushed it away from the pumps about 30 yards or so, tried to start it again and it fired up and ran just like normal. i decided to ride it back to the house, park it, let it sit a while and try to start it again. i let it sit for 15 minutes or so and again, it didn't want to start. after trying for a few mintues, i got it fired up (it was a little rough running at first, but cleared up) and decided to ride it to the dealer.
got it to the dealer no problem and described my problem. a few days later the dealer called and said that they found some water in the fuel tank. they drained it, put it all back together and fired it up numerous times and had no problem. i picked the bike up on a saturday and rode it to work with no problems. got off work and rode it home with no problems. went out on it that saturday night and had no issues. sunday i rode it to a car show in louisville kentucky ( about 1hr. and 45 minutes one way). got to louisville with no issues. the bike sat for a few hours until i got ready to go get some lunch. it fired up fine, but then started missing, sputtering and backfiring. i got it to a gas station, filled up (thinking again, maybe i was lower on gas than i thought since 80mph on the interstate takes a bit more fuel than 50 or so on the country roads). no dice, still sputtering and stuff. i finally got to where we were going to eat lunch and parked the bike. after we ate, i came out, fired it up and it ran great. by this time of course, i'm thinking,"what the #$%* is going on?!?!?!?".
i went back to the car show and hung out for a while. when i left the car show, the bike fired up and ran great for the 1st half of the trip. i stopped to get gas again and shut the bike off. after i filled up and took off again, i got maybe 1/8 of a mile and it started sputtering and backfiring again so badly that i couldn't keep it running. i pulled over and tried to restart it. again, it was hard to start and when it finally did, i got the same backfiring and sputtering. i was able to keep it running long enough that it cleared itself up and ran fine the rest of the way home.
since then i have had probably 5 or 6 more instances like this and i'm at my wits end!!! has anyone else had this problem? the dealer is again giving me some b.s. about water in the fuel. i have run probably no less than 10 tanks of gas through it and personally feel like the "water in the tank" thing is b.s. somebody help me please!!!

FattRat · 08-23-2006

It woulda been found and resolved by now, but my bike behaved like that just prior to the ground coming loose on the battery while flying over a goat-trail of a road.....

zaqtronic · 08-23-2006

I'm thinking electrical connections too... like fattratt just said.

Someone else recently posted something about their carb needles getting varnished over. Maybe you have something similar - like a bit of gunk in the carbs.

Otherwise, it may be best to go over all connections (electrical and fuel) from end to end with a fine toothed comb.

Good luck!

ZAQ

[ This message was edited by: zaqtronic on 2006-08-23 21:04 ]

Indypsychobilly · 08-24-2006

thanks guys,
here's a little update.

it isn't the vaccuum tube from the tank. i started it and let it warm up and it was running and revving fine on the choke. i shut the choke off as it warmed up and it would idle fine, but begin to sputter and backfire as i went up in the rpm range. i unscrewed the gas cap and had the same problem, so it isn't a venting issue.

i have considered the kickstand switch, but now i'm thinking that looks less like the problem. it seems to do it after the bike is warmed up.

also, i have drained the float bowls on 3 or 4 different occasions, so i don't think water in the fuel is the issue.

the crankshaft position sensor seems like it might be the most logical fix. i'll let it cool down and check the resistance figure this afternoon.

Multibob · 08-24-2006

Have a look at the vacuum caps on the carb's, I had a similar prob, and found that one of the caps would leek after it was warm and it would cough and splutter and then not start.

GrahamC · 08-24-2006

Trash in a carb(s)/ fuel line or electrical connection is what it sounds to me.

RedBird · 08-24-2006

Sounds electrical to me...crankshaft position sensor is the first thing I thought of; however, coils have been known to do strange things and some on this forum have had coil problems. Make sure the plug wires are seated good in the coil, also.

Larry

Indypsychobilly · 09-07-2006

well.....now that i have finally gotten my meter back from the friend that borrowed it, i can't get the bike to act up again do i can check the resistance across the sensor....grrrr!!!!

Colin_In_Ottawa · 09-07-2006

Well I havent got my bike back from the shop yet to verify this, but for a similar complaint, my dealer says they found that by wiggling around the ignition switch that they could duplicate my cutting-out and no-starting complaints. They have a switch ordered for it.
Try some wiggling and light tapping on the switch and wiring and see if it acts up. Ye never know.
Intermittents are a tough problem to fix.
Colin