Triumphrat

Beemie

Can the ignition of a T140 be set with a dwell meter?
If so, what angle setting and how is it accomplished as I've never seen a 2 cylinder dwell meter?

thirdbike

Don't mean to be sarcastic but seen too many burnt pistons etc.
If you want all kinds of headaches use any other technique you want. If you want to set your timing and be sure it is dead on use a timing light - period. If you want to forget about timing issues permanently, get a Boyer.

Beemie

Talking two different things there.
Dwell meter sets the points, not the timing.
I use both dwell meter and timing light on the old car.

johnny black

Hi Guys,I'm a newbie overhere so Hello againnever had an old trumpy but plenty of time on BSA twins,I always thought dwell was the time contact points stayed open ? Yeh that sounds right,,,? ie the position of the breakers in relation to the cam lobe,with 2 sets of points putting a dwell meter on em could be done in theory-the way its been done since time immorial as you know is to have both sets opening at the top of the lobe-15 thou I think ?,locking it THEN TIMING IT,So to answer your question-dunnoJ.B.

Caulky

In my limited experience with points, surely the dwell is set by the gap.
Bigger gap-longer dwell and vice-versa.
Or are you asking if the timing (the point where the breaker begins to open) can be set normally, but the length of time until closing can be varied? I`m just asking myself why anyone would want to do this?

johnny black

Nah your missing the point,the dwell is how long the contact points stay open and this is dictated by the position of the points in relation to the housing,if it stays open too long it'll bump over and you wont get a true timing on both cylinders ie one cylinder will run hot,your bike will start running on 1 piston,you'll check fuel,you'll probably look at your plugs,coils etc,most parrell twins have got a coupla firing spots..anyhoo thats why I use the the elektick stuff J.B.

Beemie

I think most are onto the idea, and I should have said "set the points" via dwell meter.

We used to do that all the time with the dual point Mallory distributor on the old Chevy hot rod.

So does anyone doe that on their Triumph and if so, with what meter and how.

I am thinking a 2x multiple of a 4 cylinder meter reading, but not too sure.

GrandPaulZ

I would set the points exactly as stated in the factory workshop manual.

Doing that will automatically result in the optimum dwell angle for the Triumph, for regular road use.

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Beemie

We've done that since wheels were made of stone.

Applying a modern technique to an old horse can be fun.
I gave up using IBM punch cards so long ago.

johnquinnell

Hey Beemie I'm with ya man. I have been trying to find out the answers to the question you are asking for years now without success. The method you are suggesting (dwell meter and timing light) made tuning my old Honda 750-4 so much easier and effective than just checking the contact points gap with a feeler guage. I'm certainly not here to challenge those who prefer the tried & proven way the Triumph manuals suggest. I'm just aware as you suggest, that there are other ways to confirm the dwell of your points are correct and equal with each other on Triumph twins, it's just nobody seems to know what that dwell angle should be and if there is a dwell meter out there capable of use on a twin cylinder engine? I'm glad I'm not the only Triumph owner that has pondered this question and am now more determined than ever to see if I can make this work.
JQ