[mfp4073]

This is going to be hard to describe because I cant seem to find any pattern in it. So im going to give you some examples. It seems to be getting worse, but ive been having this issue for over a year with some new symptoms developing recently.

Bike is 04 t100, mostly stock and no modifications to the drivetrain. 30k miles. Owned for since 2014 with only 2k miles on it then.

Stalls like you hit the kill switch. ALWAYS restarts with no issue or hesitation. Cold or operating temp doesnt seem to make a difference. If anything its better when warm.

While sitting at a light (or my driveway), idling fine at 1200rpms then will just die. Hands off throttle, in neutral, clutch out. Might do it once every once in awhile like once at 10-15 lights. might do it 3 or 4 times waiting for the light to change.

While applying power from a stop, feathering clutch out while taking off. again, might not do it for 30-40 miles then it will pop up. This is the one that is going to get me as sometimes Im applying power around a corner and when it stalls the bike almost goes down. When it does this im fast enough that I can pull in the clutch and give it more throttle to keep it from stalling. But its not fun.

Something recently new in the last few days is that it will "stall" while riding consistent speed. Today it was 55mph 3500rpm, top gear and it cut out several times in 10 seconds. I watched it drop about 500rpms and lurch the bike forward. Im not sure if it "recaught" or if it "pushstarted" itself. This is a 10th of a second event. Just enough to change the weight disposition of the bike/rider and then the power is back.

Sometimes sitting idling it will do something. Like an internal backfire? I dont know how to describe it. But again, it will drop rpms and I will feel the side covers almost "kick" in my knees. Its done this since purchased at only 2k miles.

Sometimes it will feel like it "hiccups" when I hit a bump. But maybe once every 400 miles.

The other day after my ride home, 35 miles, I pulled up in the driveway, put it in neutral, let out the clutch, put side stand down and when I rocked it onto the side stand it stalled.

Im feeling this has to be electrical, but its so random. Some days better than others. I cant make it do it or effect it in any way.

This is so vague....I dont know if we can get anywhere.

 

[Back2-2]

It sounds like electrical contact issue. Here are items I would be getting a volt meter out and investigating.

Side Stand switch. There is a thread going right now on how to check that.
Neutral safety switch lead loose. Under side of engine right behind oil filter.
Ground leads behind main frame mid bike.
ECU under seat - there has been issues of the seat rubbing and causing the connector to go open on bumps or seat weight.
Engine kill switch for corrosion.
Ignition switch for corrosion or being loose or worn contacts.

Wires and connectors in the headlight bucket for shorting to ground.
General check of all electrical connectors for corrosion or being loose.

Here is the link to side stand switch troubles.
https://www.triumphrat.net/air-cooled-twins-talk/795769-side-stand-switch.html

 

[Baltobonneville]

IF it's not an intermittent connection, it sounds very much like a failing ignitor. Mine cut out intermittently and unpredictably until one day I couldn't start it at all anymore. Unfortunately, there's no way of knowing that unless/until you swap in a new or known good ignitor.

Other things to check are the ignition coil and the crank position sensor ("pick up coil"). I replaced both of them before I got to the ignitor, which fixed the problem immediately. I even replaced the spark plugs, although I didn't think that they were causing it.

 

[Back2-2]

IF it's not an intermittent connection, it sounds very much like a failing ignitor. Mine cut out intermittently and unpredictably until one day I couldn't start it at all anymore. Unfortunately, there's no way of knowing that unless/until you swap in a new or known good ignitor.

Other things to check are the ignition coil and the crank position sensor ("pick up coil"). I replaced both of them before I got to the ignitor, which fixed the problem immediately. I even replaced the spark plugs, although I didn't think that they were causing it.

Great ideas from Mr. Baltobonneville.
Only reason I would not start there is that he reports this condition happens at odd times and not just when hot which is what I recall most people report for crank position sensor problems. Most do not start back up right away until allowed to cool. Certainly worth a ohms check on it though.

Hopefully OP'r has a service manual. Looks like some good investigative work is going to be in order.

 

[mfp4073]

Thank you for the replies. I was hoping this sounded like something that everyone had heard of before. It will be awhile before I can get to detailed testing as I have other projects mid stream right now. I do have a service manual

@back22, I dont believe the side stand switch can be an issue due to the fact that its out of the loop when its in neutral, ie you can put the side stand down when in neutral and im having the problem at that time (as well as everything else).

I have seen no evidence of corrosion anywhere on the bike at any time. But it does get ridden in the Florida humidity and often rain.

Something also that has to be considered is there is more than one issue manifesting.

BTW, im pretty much cursed mechanically. Not that I cant do the work. But everything is always the worst, hardest and most random problems that no one has ever heard of. I spent three weeks with a non running truck after an engine rebuild/swap because the firing order in the manual I had was wrong and couldnt make sense of the symptoms. Also last year was 2 brand new front motorcycle tires that caused head shake but made 8 months apart? One bad one...ok. 2 bad ones in a row. only me!

 

[mfp4073]

Also, do you all think this is something that will have to be in a "fail" condition for my electrical tests to be valid?

 

[Back2-2]

Also, do you all think this is something that will have to be in a "fail" condition for my electrical tests to be valid?

That is tough to answer. You may spot something like a loose connector right off. But you may also need to find a suspect area and by touching or moving the item find the problem why checking continuity.

I agree with what you stated about the side stand switch - but do not rule it out. It cold be faulting while it is in the up position if the connector or internals are shorting. Same with the neutral safety switch.
Easy things first and go from there. Good luck, everything is fixable.:smile2:

 

[rweb]

Also, do you all think this is something that will have to be in a "fail" condition for my electrical tests to be valid?

YES... However the side stand switch can be bypassed by unplugging the three wire connector behind the left side cover and jumping the two outer wires of the harness side of the connector. There is a post about this in the Twins Talk section, Side stand switch post.

 

[mfp4073]

Im 35 miles one way to work, 4/5 of that is highway speeds

On the way to work, almost nothing. just a few of the stalls at lights. On the way home it was doing that "dropping out" at constant speed a bunch. It seemed like it was worse at lower rpms under 4k.

I will do some limited testing this weekend between projects.

Thank you again!

 

[mfp4073]

on a sunday morning coming down and listening to the stooges I think I might have come up with my problem. (edit...confused). I first tested the resiatnace of the pickup and got 590ohms. Then pulled the coil and tested the primary side and got 1.5ohms. I figured I found my issue. But then further messing around found "most of the time" it was at 4.8-5 ohms. But sometimes it would test at 6 and others at 4.5? I cant really explain that. then after some more messing around it went back to the 1.5 ohms reading and as low as .8. I verified this with 2 multimeters (both craftsman models) I get no results out of the secondary side, but from what Im reading you cant test that with a multimeter?

I have a triumph service manual and cannot find any values for the coil. its only part of one page that says "remove leads, remove 2 screws, remove. Installation opposite of removal"

***edit, i found a video (will post below that talks about testing the secondary side but I cannot get any reading from the secondary side at all. So im a bit confused.

 

[rweb]

To check the secondary side of the ignition coil, remove the plug wires from the spark plugs and probe/test from one plug wire end to the other, through the coil. I don't know the resistance, maybe 15k ohms give or take? If you find an open circuit, remove the plug wires from the coil and check each spark plug wire individually for an open. If not check through the coil, from one secondary post to the other. Do a search on this forum for coil test.

 

[mfp4073]

nothing I did was able to get any numbers from the coil other than the primary side as mentioned. This would make sense if the bike wasnt running but it has been running (with issues) right up until I took it apart for testing. testing from the pos side of the primary gets nothing (open) to any part of the secondary.

 

[rweb]

The primary and secondary coils inside the ignition coil are not connected to each other. When you test from one primary (+) connector to the other (-) you are testing the resistance of that one wire one end to the other that is coiled inside the ignition assembly. When you test from one HT post to the other HT post you are testing the resistance of that one wire from one end to the other. If the primary side is broken/ open the coil probably won't work at all. If the secondary winding is broken or a plug wire has a small brake/open the spark can sometimes jump the gap and fire the plug intermittently. So if the HT side from spark plug cable end to spark plug cable end checks bad/open it is possible that it will still fire the plugs. Also make sure the spark plugs are good. Hope this helps.

 

[mfp4073]

thanks. Plugs were replaced recently (it had been needing to be done anyway) to no change.

Sounds like a new coil is the first course of action to try. At worst I will have a backup coil.

Thanks everyone. I will post up the results.

 

[coachconnor]

thanks. Plugs were replaced recently (it had been needing to be done anyway) to no change.

Sounds like a new coil is the first course of action to try. At worst I will have a backup coil.

Thanks everyone. I will post up the results.

I had to replace my coil and then ignitor on my '03 due to intermittent shut offs and seeming to run on one cylinder. I don't know if the coil going bad can affect the ignitor or vice versa. Is there any one else in your area with a similar bike who could let you swap out the parts for a test? Sure could save you a heap of time and aggravation. By the way, testing the coil with a multi meter is a waste as some coils break down as voltage is applied. An ASCE auto instructor checked mine and it showed it was good. It wasn't.

 

[mfp4073]

well, after a coil replacement that tested exactly the same as my old one I was letting the bike idle and it died. Couldnt get it to restart. Pulled the tank and tested the new coil again, did a little looking around. Nothing. Tested for startup, started fine. Put the tank back on, started and ran fine. Was messing around and put my hand on the area where the seat should be and it died. wait...what? Started it back up and started "pushing on things", died. Started back up. Finally traced it down to the plug going into the computer. Initially pushing down, even gently, on the wires circled caused the stall. I pulled it, cleaned and lubed the contacts and have reached the point where I can wiggle it fine with no stalling. Wont be able to do a road test until monday. Will post results after that.

 

[Back2-2]

Excellent find.
Item #4 on my list for you when you posted your problem.
"ECU under seat - there has been issues of the seat rubbing and causing the connector to go open on bumps or seat weight."

You should be good to go now. If I recall some people cut out that area in the seat pan that rubs on the ECU.

Now you have a spare coil for road trips.

 

[mfp4073]

I replaced the coil with a nology coil, from my reading they are supposed to be more reliable than the stock coil.....but who knows. my seat is an aftermarket british customs one. Before I started cleaning the connections I very carefully tested. Pushing on the computer, the housing for the wiring harness, etc wouldnt do it. I could wiggle the connector with no results. it was only when I pushed down on the wires themselves would it fail.

Thanks for all the help and suggestions everyone!

 

[Back2-2]

I replaced the coil with a nology coil, from my reading they are supposed to be more reliable than the stock coil.....but who knows. my seat is an aftermarket british customs one. Before I started cleaning the connections I very carefully tested. Pushing on the computer, the housing for the wiring harness, etc wouldnt do it. I could wiggle the connector with no results. it was only when I pushed down on the wires themselves would it fail.

Thanks for all the help and suggestions everyone!

I did the same upgrade trouble shooting a carb problem. So I have a spare OEM coil also.
Glad you got it all fixed. :smile2: Nice when it works out that way. Thank you for the update also. Everyone likes to know what the fault was and how it was fixed.

 

[mfp4073]

well great news after my 75 mile round trip ride to work. ALL symptoms are gone, not one incident of anything described in my first post. Not only that but its idling better and requires the choke for less time even though we are in a cold snap (42 degrees when I left for work this morning). It feels like its running smoother and a little crisper too. I dont know how much of this is the plug, the coil, and/or psychological. My mom has always been completely convinced that her car runs better when its been washed. One of the symptoms, the "backfiring through the carbs/coughing" symptom has been going on for years now and is also gone. Im considering putting the factory coil back on when i end up pulling the tank next just for testing purposes. The replacement was a nology brand, so I dont know if thats made a difference. In some other places online i read people saying they got improvements and improved gas mileage from replacing the stock coil with a nology. Will post up if I see any fuel economy difference after a few tanks and again if I put the stock coil back on just for completeness so anyone else wandering in will have a full picture.

Thanks again everyone!