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Discussion Starter #1
Okay. Intermittent-well, more on than not-fault on my Thunderbird.

Started off with bad misfiring and cutting out at low revs when hot. Faulty coil. Coil replaced.

Problem better, but has not gone away.

Replace all sparks and coils.

Slight improvement, but still not right. Cutting out throughout the rev range and dying when hot at low revs.

Replace ignition pick up.

Another improvement, but still not gone. Misfiring at 3500 revs and below and cutting out at low revs when hot. Fine at higher revs and on full acceleration.

yes, there is fuel.

At low revs, when the engine cuts out, it will not restart unless the ignition is switched off or the kill switch is activated-all when bike is hot. MUST be the ignition system-I haven't replaced the HT leads yet.

I'm running out of ideas here. Any help appreciated.
 

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A buddy of mine had a very poorly running bird at a Triumph rally a few years ago. It turned out his air filter had lots of oil in it because of a bit too much oil added at each oil change. After a while the build it was pretty great. He took out the filter and cleaned it in the parking lot and sure enough it returned his bird to fine running shape. I am not a mechanic and not sure if your symptoms indicate anything to do with the air filter but I figured I would just pass that along.
 

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Discussion Starter #3
Thanks. I replaced the airfilter about 4K ago, so I really hope it's still okay. Took ages-how did your friend do it in a parking lot? Homage!
 

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yes, there is fuel.

Worth checking the carb's if all else fails as my 96 speed triple had a similar problem some years ago and I attacked it the same way as you (very expensive).In the end I pulled the carbs and fitted another set off a project bike and problem was gone.When i stripped the original carbs there was crap in the pilot jets on 2 carbs.They worked fine on another bike.
Good luck.
 

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Vonbonns may still be correct about the air cleaner being clogged with oil. All it takes is slight overfill and oil ends up being spit into the air cleaner. If you changed it in the process of eliminating this problem, you would know thats not it.
 

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I think the boys are on the right track with fuel, sounds like its far too rich.Take your plugs out and check colour, Ireckon theyll be well sooted/black, Rob.:)
 

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Rough running at low revs

I would take a closer look at the electrical system - particularly the battery and charging circuit for loose or dirty connections, low alternator output. Pull the plug on the headlight bulb - does that help the problem?

I don't think a problem with the fuel delivery system would manifest itself only when hot.

Courtney in Seattle
 

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"Another improvement, but still not gone. Misfiring at 3500 revs and below and cutting out at low revs when hot. Fine at higher revs and on full acceleration"

Ron, that still sounds EXACTLY like a problem I had and three nology coils fixed it.
If you search my threads in my profile you'll see that my symptoms were just what yours are both times. (two threads).
I got lucky the second time because the #1 coil started going south and the tach (which reads #1 coil) became erratic.
Sorry Uncle Triumph, but GIL coils are JUNK!
 

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By the way I still have two good GIL coils and I'll be happy to send them to you if you want to replace them for troubleshooting purposes.
Again, by the start with the two you didn't replace.
Holler at me I'll be glad to send them off to you.
 

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"At low revs, when the engine cuts out, it will not restart unless the ignition is switched off or the kill switch is activated-all when bike is hot. MUST be the ignition system-I haven't replaced the HT leads yet."

Uh-oh, rethinking that it sounds like you have a problem like I have now.........Sort of.

You're still welcome to the coils though.
 

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I'd have another look at the ignition pick-up sensor, I note you have replaced it but the symptoms of a bad one are still there.


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Ride on ! :)
 

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Discussion Starter #15
By the way I still have two good GIL coils and I'll be happy to send them to you if you want to replace them for troubleshooting purposes.
Again, by the start with the two you didn't replace.
Holler at me I'll be glad to send them off to you.
Thanks-v generous but I've got some spares. Ta.
 

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Discussion Starter #16
Well, the carbs are clean, balanced, valve gaps checked, coils and ignition pick up all replaced. All I can think now is that it is the CDI. Piss.

It's running well at high speeds but will cut out at low speeds, when hot. I then have to turn the ignition or kill switch on and off. CDI seems all that's left.
 

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'scuse me

But this still sounds like a low-voltage situation to me have you put a voltmeter on the battery and checked for a voltage drop to the ignition? If you pull the plug to the headlight, does the problem change at all?

C
 

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Discussion Starter #18
Next job, then. However, the main symptom is cutting out completely at low revs, then having to turn off the ignition and on again, or it won't start.
 

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Note that there are sidestand and gearbox neutral inhibit lines going in to the Igniter. A ground short or some flaky switches/connections could be the cause of the problem. Low revs/ high revs behaviour might result from how engine vibration affects things.

If it does turn out to be a faulty Igniter unit - hopefully you can borrow one to swap & get a definitive answer - I've been in touch with a Czech company who make an aftermarket unit.

This is the thread I started:

http://www.triumphrat.net/hinckley-classic-triples/99853-igniter-remap-and-low-cost-stock-replacement.html

I was last in touch about a week ago, they replied that they hadn't yet obtained Triumph connectors (to plug in to T3xx looms) but were 'working on it'....

My interest is in the programmability of their unit & very reasonable price for their unit - around 140 euros. I'm sure they can supply a unit with standard ignition advance curve to just plug & go for people who just want to replace a faulty stock igniter....but we need them to offer their unit with the right connector for us.

Whether you need a new igniter or not, it might help speed up their 'working on it..' if you were to make an enquiry ?

They're at http://www.ignitech.cz/english/aindex.htm & contact details are there.

(BTW - I've no financial or other connection with this Co.)

Mike
 

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Voltmeter + Electrical Schematics = Troubleshooting

Next job, then. However, the main symptom is cutting out completely at low revs, then having to turn off the ignition and on again, or it won't start.
What exactly happens if you don't cycle the ignition on/off? Starter just click? Nothing?

I would not be surprised if you found a significant voltage drop across your ignition switch contacts and/or kill switch. I think that the reason it's running better at higher revs is that the alternator output voltage is high enough to overcome the effects of the voltage drop, which may well turn out to be bad or dirty contacts in the switch.

I don't know if the switch tumblers and contacts are contained in the same assembly. I wonder if simply spraying electrical cleaner or WD40 into the switches and working them back and forth will help. May as well shoot the side stand switch while you are at it.
 
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