1993 Trident Misfire/backfire

Hi Ecossie, and welcome in Am sure someone will be along to help very soon

 

Re check pilot jets. (Next to main jet). You will need to poke some copper wire through tbem. Airline or ultrasonic cleaning don't work as holes are too small. 90 % of running issues are blocked pilot jets on these.

 

I’m not sure on the triples but the fours have two fuel feed lines to the carbs.
If you’re using a fuel rig rather than the tank it’s worth checking that all carbs are getting fuel properly.

 

Having similar problem with mine mate. Middle cylinder not firing, coil looked burnt on the outside, so must have been getting seriously hot. fitted 3 new coils, and rebuilt the carbs, but no better. tomorrow i am going to check the plug leads for good fit, and fit more new plugs. Here's hoping.

 

Check manifold for leaks , running lean because air is getting in after the carbs ? This will cause poor response and running at all revs. Easy check , use WD-40 or similar or Aero Start , spray sparingly around the inlet port/rubber on the cylinder you suspect....

 

Thank you for the reply.
It had new inlet rubbers fitted a couple of months ago. But if the electrical side does not fix it, i will do the leak test.

 

Have you checked the valve clearances as they tighten up with use.

 

Not yet, just fired it up, and running fine, Now going ro ride it and see what happens?

 

You know it will play up again dont you? Just when you think the issue has gone away.

 

Ran like a bag of shit, on 2 cylinders, for about 3 miles. then bogged right down to barely running at all for the last mile. Heap of of shit, needs setting fire to. Next time out, that is what the fucking thing is going to get too. Worse bike i ever had, Fuck Triumph, and their 2 bob design team.of wankers.

 

I guess you ain't happy then , right. The bike is close on 30 years old and needs love and attention, I dont suppose you perform as well as you did when you were much younger. Dont throw your toys out of the pram I'm sure you can get it sorted, these bikes are very reliable just need tlc first.

 

Fair comment. That was just a drunken rant, from a seriously pissed off bloke.

 

Lol been there done that.
Dont give up.
Good luck mate

 

That would be quite amusing if it wasn't serious.

There's more than a few people on here who have covered many trouble free miles on one or other of the T300 range of bikes (Trident; Daytona; Trophy; Speed; Sprint and Thunderbird) so the "2 bob design" isn't really a candidate for criticism. Ask Stevethegoolie! That said, when they're bad, they're very, VERY bad! But that's true of pretty much any mechanical automotive device.

Anyway, drunken rant aside, I can understand the frustration. But, stick with it, if you can, the rewards are definitely worth the effort. There are some things that you really must check and try :-

1) @t552 is absolutely spot on - the pilots on these are a right, royal PITA. I've known people have them ultrasonically cleaned and STILL have running issues. Thin electrical wire, shitloads of carb. cleaner, the patience of a Saint and a sacrifical goat to the Gods of Motorcycling will be the minimum requirement to overcome residue-blocked pilot jets.

2) T3s seem to be highly sensitive to airbox modifications. If yours doesn't have the original airbox, see if you can find a secondhand one to try. Also, make sure that ALL of the connections to the airbox are on and secure, including the breather hose. Changes to the intake system can make a big difference to how they run. Or if they run.

3) The coils are generally reliable but they aren't the best in the world. There are, apparently, better coils out there (nology?) so that may be an avenue to explore. @t552 might also be able to help if you do find the coils to be problematic - not sure if it's still the case but he used to be able to supply stick coils that are a big improvement.

4) It's a well known fact that 95% of all electrical misfires and poor running issues are caused by carburation problems! It's a sort of inverse Sod's Law. An early T3 with Mikunis is the living proof of this immutable law.

5) I have a 'spare' ECU somewhere that I'd be happy to let you try - on the strict understanding that you'll pay the postage and return it to me undamaged when you've finished the test. Let me know if you're interested. And trustworthy.

Finally, if all this fails then consider contacting Clive WOOD. He is THE guru on all things T3. His place is in Lincolnshire but 240 miles isn't THAT far and if you can get it booked in with him ( he is ALWAYS busy and booked way in advance) and transported there then you're pretty much guaranteed a solution. You may also be able to watch him work on the bike and, therefore, learn a lot more about it.

Good luck with it all. I'm pretty sure that you'll find that the rewards from the bike will quickly make you forget the frustration - there's something about the exhaust note and grunt of an early Trident that is wholly addictive. Had one of mine from new in 1992 and would never, ever willingly let it go.

 

Thank you. I think i am going to need it.

 

Just a long shot here - the Mikuni carbs (I presume yours are Mikuni?) each have a vacuum take off point on the top. 1 usually goes to the vacuum operated fuel tap and the other 2 are capped off with a rubbery plastic shroud thing (technical term).
Did you check they are capped - they are plastic caps/pipe and prone to breaking off too, or cracking around the base. There should be a very small "O" ring under the tube in the cap that seals it to the top of the carb. The vacuum tubes are used for balancing the carbs, but if left uncapped you have a nice route for air to get sucked into the inlets, making it run with a weak mixture.
My '96 Sprint ran rough as a badger's bum until I stripped and rebuilt the carbs (full of nice ethanol "cottage cheese") a couple of times - even after the first clean, one of the pilot jets managed to get clogged again. One carb had a vacuum tube that was cracked around its base which I fixed by drilling the hole out and gluing in a small brass tube, and a second carb was missing the tiny "O" ring.
Balancing them properly helped too.
Mine has the standard air box, but with a K&N style filter in it (from Sprint Manufacturing), which it seems happy with.

Dunno if the above is helpful, but maybe it will trigger some ideas...

 

Does it make any difference which carb the vacuum hose fits onto ?. And i never got any O rings to fit inside the caps, with my rebuild kit. Will not having them, make a difference to the running ? Also, the 3 inlets on the back, top of the carbs, show hoses on them in the book. How long should they be, and where should they go ? I have 3 cone filters, not the original airbox. Thank you.

 

I have a Sprint with Mikuni carbs (the Keihins would be different), but the left (as you sit on the bike) carb top vacuum outlet has a tube to the fuel tap (again left side of the tank), and the other two are capped off, so sealed.

Sorry for the crappy image, but the best I could find -- the arrowed tube is the one I am referring to, and faces the front of the bike on each carb.

My manual shows the o-ring as Item 3 in the diagram.
If you are missing the o-rings, then it could possibly be leaking air and make the mixture run lean, especially at tickover and low throttle. Similarly if any vacuum points are open, then they will allow air straight to the inlet bypassing the carbs.
If you have the Keihin carbs, you will need to look up the information on those as they may be different.

I have heard that cone filters do cause fuelling problems, and can be a real bar-steward to set up properly.
Hope this is of help.