Trident T160 Running Problems

[Peter Waller]

Hi all. I am a new member and have just purchased a Triumph T160 Trident and it does not run very well. It starts from cold great and ticks over fine and when you rev it no exhaust smoke and a very quiet engine. And when you ride it all is well untill you have done a mile or so and it warms up. Then it lags when you open it up and gets progressively worse as the engine has been running for 10 minutes or so. It starts holding back and some popping from one of the exhausts. And if I switch it off it is very difficult to start again but will fire up straight away once it has cooled. I took the air filter out which was oiled up and the plugs are always sooty after being cleaned and ridden a couple of miles. It has only done 1000 miles in the last 15 years and 16000 in total. Any ideas??? Please! Carbs/fuel or electrical coils/plugs/leads??? Any help would be greatly appreciated. Thx Pete.

 

[grandpaul]

, Pete!

Paper air filter should be dry. Wire mesh and cloth type should be LIGHTLY oiled (hardly visible). Foam should be VERY lightly oiled.

Failing the above would PARTIALLY explain the sooty plugs.

You really need to address the filter situation, install new plugs, and go out on a "plug chop" run immediately, before the plugs can begin to foul from improper jetting.

JETTING is likely the cause of your woes. Overly-rich jetting aids in starting when cold, then progressively fouls the plugs the more you ride.

 

[grandpaul]

Take a spark plug wrench with you, and a rag.

Get to the closest place where you can run up through the gears to 3rd gear @ 5,000 RPM and then all at the same time, snap off the throttle, pull in the clutch, and kill the engine. Roll to a stop on the side of the road, pull the plugs and have a look.

Light gray/tan = good

PROBABLY dark gray and/or sooty = too rich

You need to LOWER the slide needles by RAISING the little clips one notch.

Repeat plug chop and needle adjustment, till it runs right.

If your clips are already at the top, you need the next size smaller main jets.

 

[Peter Waller]

Take a spark plug wrench with you, and a rag.

Get to the closest place where you can run up through the gears to 3rd gear @ 5,000 RPM and then all at the same time, snap off the throttle, pull in the clutch, and kill the engine. Roll to a stop on the side of the road, pull the plugs and have a look.

Light gray/tan = good

PROBABLY dark gray and/or sooty = too rich

You need to LOWER the slide needles by RAISING the little clips one notch.

Repeat plug chop and needle adjustment, till it runs right.

If your clips are already at the top, you need the next size smaller main jets.

Thx for the replies and will certainly try your advice. Someone also said the tappets may be to tightly adjusted??

 

[grandpaul]

Thx for the replies and will certainly try your advice. Someone also said the tappets may be to tightly adjusted??

I don't think so.

Also I don't think you have any other issues, as you said the bike starts right up when cold, idles well and runs fine with no smoky exhaust, till it starts to heat up.

Although, you could be riding that fine line of valve adjustment where heating up just gets past the "too tight" point...

 

[Rudie]

starts from cold great and ticks over fine
when you ride it all is well untill you have done a mile or so and it warms up. Then it lags when you open it up and gets progressively worse as the engine has been running for 10 minutes or so. It starts holding back and some popping from one of the exhausts. And if I switch it off it is very difficult to start again but will fire up straight away once it has cooled. I took the air filter out which was oiled up and the plugs are always sooty after being cleaned and ridden a couple of miles. It has only done 1000 miles in the last 15 years and 16000 in total. Any ideas??? Please! Carbs/fuel or electrical coils/plugs/leads??? Any help would be greatly appreciated. Thx Pete.

Standard Amal carburettors? All bodies marked "A626", right and centre marked "R76", left marked "L77"?

If so, are they fitted with 'chokes' (air slides)? If they are, standard operating lever mounted on the left of the gantry mounting the carburettors, the lever operates one cable that runs into a splitter, from which one cable runs to each carb top.

If the air slides are fitted, are you operating them correctly? When the lever is turned so the cable is pulled tight, choke is 'off'; when the lever is turned so the cable is slack, choke is 'on'. If you are not familiar with British bikes, this is opposite to the way the choke operates on other makes, particularly Japanese.

Using the choke the 'wrong' way will give the symptoms you describe ...

I don't think you have any other issues, as you said the bike starts right up when cold, idles well and runs fine with no smoky exhaust, till it starts to heat up.

Surprising assertion. In addition to the 'choke' issue, the symptoms you describe could also be an intermittent electrical problem - the component or connection works when cool, fails when it heats up. If this is the cause, the usual failure pattern is the periods between working and failure become shorter and shorter before complete failure.

What plugs are fitted? Cheapest would be Champion N3, NGK B8ES or equivalent.

What plug caps are fitted?

What ignition is fitted; points or electronic? If electronic, what make, model?

Be aware, while "plug chops" used to be a valid diagnostic tool, modern British petrol is poor at giving the colours @grandpaul describes (he is in Texas). Also, "plug chops" are a waste of time if the choke is being operated incorrectly, the wrong plug grade is being used, there is an electrical problem, a well known wear point in standard carburettors has not been corrected.

tappets may be to tightly adjusted?

The manuals say 0.006" inlet, 0.008" exhaust. However, Doug Hele (father of the triple) always advised 0.008" inlet, 0.010" exhaust. In reality, triple tappets aren't the easiest things to set correctly so, if you think you might be making an error, make it to the larger side of six thou and eight thou.

 

[Peter Waller]

Thank you all for all your replies! Brilliant thx and will commence operations tomo! Will let you know how I get on

 

[Peter Waller]

Here is the bike

 

[grandpaul]

Using the choke the 'wrong' way will give the symptoms you describe ...

DOH!!!

I forgot the easiest of all possibilities!

@Rudie is probably correct, AGAIN.

 

[Lordmac]

Here is the bike

Pete, that is a gorgeous T160! Looks near as good as my '78 T140v! What year is it? I could guess since it has those 1980s clocks. Oh, and that Commando . . . nice, two of my favorite bikes in one photo. Keep us posted, fer sher, after doing the "first things first" checks. I am thinking carb issues of some sort, but you never know . . .

 

[Rudie]

T160
What year is it? I could guess since it has those 1980s clocks.

T160 only made between late 1974 and early 1976, always considered the 75 triple by NVT.

The T160 top yoke, clocks mounting, warning lights and ignition switch mounting, and the electric start Commando handlebar switches, were adopted by Meriden for 79-on twins.