1979 Triumph T140 MK2 carb specs

seattle##gs · Monday at 8:45 PM

Does anyone know what size the pilot jet is? Currently I have a #20 pilot but can't get it started. I have a feeling it should be a #25
MK2 carbs.

marshg246 · Monday at 9:29 PM

seattle##gs said:
Does anyone know what size the pilot jet is? Currently I have a #20 pilot but can't get it started. I have a feeling it should be a #25
MK2 carbs.

According to AMAL:
MJ: 200
PJ: 25
NJ: 105
Slide: 3

Fast Eddie · Tuesday at 12:17 AM

This can be a minefield !

Triumph and Amal developed special (unusual) settings to get through EPA. But not all bikes were fitted with them. EPA and none EPA settings are very different and several components, whilst being physically interchangeable, are NOT interchangeable in terms of how they work!

First thing you have to do is ascertain whether you have EPA or none EPA carb set up.

Second thing you have to do is decide which you want!

I am certain that inappropriate mixing and matching of these parts is the cause of many people disliking mk2 carbs.

My advice is to fully strip the carbs and build them up to full none EPA spec.

John Healey did a service to mankind by breaking this down clearly. Sadly the Amal info, as well as the workshop manual, is wrong.

You MUST find and remove the infamous ‘air jet’ if you want none EPA carbs otherwise you’ll NEVER get it right.

I’d draw your attention to posts #14 and #28 in this thread:

Thread 'Struggling with MK11 carbs'

Nov 1, 2018

Gents, I’m struggling with the mk11 carbs on this T140 I have just bought.

The carbs are brand new and fitted with 20 pilot jets, 106 needle jets, number 3 slides, 200 mains. These are the ‘standard’ settings for this bike according to Amal.

I have ensured the enriching circuit plunger is sitting properly with slack on the cables.

It is very rich. Currently, I’m only talking about low revs / small throttle openings cos it’s a newly rebuilt motor, when opened up briefly it it seems to clear, but the low end is very rich.

So I started reading up and learned that carb settings for the...

seattle##gs · Tuesday at 12:42 PM

Fast Eddie said:
This can be a minefield !

Triumph and Amal developed special (unusual) settings to get through EPA. But not all bikes were fitted with them. EPA and none EPA settings are very different and several components, whilst being physically interchangeable, are NOT interchangeable in terms of how they work!

First thing you have to do is ascertain whether you have EPA or none EPA carb set up.

Second thing you have to do is decide which you want!

I am certain that inappropriate mixing and matching of these parts this is the cause of many people disliking mk2 carbs.

My advice is to full strip the carbs and build them up to full none EPA spec.

John Healey did a service to mankind by breaking this down clearly. Sadly the Amal info, as well as the workshop manual, is wrong.

You MUST find and remove the infamous ‘air jet’ if you want none EPA carbs otherwise you’ll NEVER get it right.

I’d draw your attention to posts #14 and #28 in this thread:

Thread 'Struggling with MK11 carbs'

Nov 1, 2018

Gents, I’m struggling with the mk11 carbs on this T140 I have just bought.

The carbs are brand new and fitted with 20 pilot jets, 106 needle jets, number 3 slides, 200 mains. These are the ‘standard’ settings for this bike according to Amal.

I have ensured the enriching circuit plunger is sitting properly with slack on the cables.

It is very rich. Currently, I’m only talking about low revs / small throttle openings cos it’s a newly rebuilt motor, when opened up briefly it it seems to clear, but the low end is very rich.

So I started reading up and learned that carb settings for the...

Fast Eddie

Replies: 46

Forum: Triumph Motorcycles

This is excellent info. I was part of that thread , #37. I will give all this a try. I tried to tell the customer that these carbs are a minefield and I have to charge by the hour while sorting them out. This could take a long time.

Fast Eddie · Tuesday at 1:15 PM

Well, basically, the point of my post was to suggest that if you strip the carbs fully, re jet / needle / slide to full John Healey non EPA spec (inc removal of the air jets) you really won’t be far off.

Alternatively, feel free to try my own final settings (but I offer no guarantees ! ).

With either of the above, you may still have to fine tune, but you won’t be far out, and you’ll save many hours and lots of frustration !

baz · Tuesday at 1:29 PM

Fast Eddie said:
This can be a minefield !

Triumph and Amal developed special (unusual) settings to get through EPA. But not all bikes were fitted with them. EPA and none EPA settings are very different and several components, whilst being physically interchangeable, are NOT interchangeable in terms of how they work!

First thing you have to do is ascertain whether you have EPA or none EPA carb set up.

Second thing you have to do is decide which you want!

I am certain that inappropriate mixing and matching of these parts is the cause of many people disliking mk2 carbs.

My advice is to fully strip the carbs and build them up to full none EPA spec.

John Healey did a service to mankind by breaking this down clearly. Sadly the Amal info, as well as the workshop manual, is wrong.

You MUST find and remove the infamous ‘air jet’ if you want none EPA carbs otherwise you’ll NEVER get it right.

I’d draw your attention to posts #14 and #28 in this thread:

Thread 'Struggling with MK11 carbs'

Nov 1, 2018

Gents, I’m struggling with the mk11 carbs on this T140 I have just bought.

The carbs are brand new and fitted with 20 pilot jets, 106 needle jets, number 3 slides, 200 mains. These are the ‘standard’ settings for this bike according to Amal.

I have ensured the enriching circuit plunger is sitting properly with slack on the cables.

It is very rich. Currently, I’m only talking about low revs / small throttle openings cos it’s a newly rebuilt motor, when opened up briefly it it seems to clear, but the low end is very rich.

So I started reading up and learned that carb settings for the...

Fast Eddie

Replies: 46

Forum: Triumph Motorcycles

I'm wondering if this was the problem a mate of mine was having on his weslake
He had endless problems trying to set up a pair of mk2s years ago
So much so that whenever they are mentioned he says they are rubbish and impossible to set up

marshg246 · Tuesday at 1:43 PM

BTW, the numbers I gave are what AMAL supplied to Triumph for the T140D/T140E and they were the first ever 2930 supplied to a manufacturer as the sub-numbers were 2930/1 & 2930/2 for 79-83. They also supplied 2930/8 & 2930/9 as 81-83. The difference is that 1/2 were lever operated choke and 8/9 were cable operated choke and the 8/9 had a 20 Pilot Jet instead of a 25.

In both cases, they had a 3.5 air jet and a 2C3 needle.

Both are still available.

A set of 1/2 is ACK201 (Out of Stock but dealers can order)
A set of /89 is ACK202 (In Stock)

marshg246 · Tuesday at 1:49 PM

baz said:
I'm wondering if this was the problem a mate of mine was having on his weslake
He had endless problems trying to set up a pair of mk2s years ago
So much so that whenever they are mentioned he says they are rubbish and impossible to set up

I have a customer with a T140 using 2930/1 & 2930/2. He was fouling plugs - I had to replace his worn cold start plunger (choke), do the Triumph cross-over lever service release mod, and install a new needle and needle jet. Otherwise, his are flawless. His settings are exactly as AMAL states.

baz · Tuesday at 3:05 PM

marshg246 said:
I have a customer with a T140 using 2930/1 & 2930/2. He was fouling plugs - I had to replace his worn cold start plunger (choke), do the Triumph cross-over lever service release mod, and install a new needle and needle jet. Otherwise, his are flawless. His settings are exactly as AMAL states.

These were a pair of 36mm carbs on a rickman weslake so were never a standard factory setup
I think he went to mikunis in the end I can't remember now

1979 Triumph T140 MK2 carb specs

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