Author Topic: 1972 Triumph T-120  (Read 4743 times)

b737doc

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1972 Triumph T-120
« on: December 29, 2006, 10:56:03 PM »
Hello everyone, New to the site,  just acquired a 1972 Triumph T-120 (serial number on title is T120RVCG51184),  thats in "poor" condition, and have a few questions for you Triumph guru's.....First of all, the engine has good compression, and tranny seems to work o.k.  the coils both have about 4.0 ohms of resistance between terminals, which I hope is O.K.  There is a key hole on the handlebars, but I'm not sure if its for the fork lock, or the ignition, as I don't have the key. The headlight has a switch on it, but not sure what it does, as, of course, the battery is dead, and alot of the wiring is in bad shape, and will have to be replaced.
1) Does the bike require an "ignition key".
2) Is approximately 4.0 ohms indicate a good coil?
3) Exhaust clamps are there, but one is separated from cylinder head, nothing appears "broke" , is this good or bad?
4) The front struts are badly "pitted", is there a fix for this, or will they have to be replaced?
5) The front wheel has a broken spoke, bad or good?
6) Brake pedal is on the left, shifter on right. Am I gonna go over the handlebars when I inadvertently down shift with the brake pedal?
7) I need a seat, front and rear fenders, right side filter cover and triangular "fill in" panel, and fuel cap. How hard is it gonna be to get these parts?
8) I found a small square electrical component with a little "squirrelly" coil coming out of it, what the heck is that?.
9) What the heck is a "pre-unit"?
10) Do you have to have a good battery for the plugs to fire?
  Sorry for being such a moron, but I have high hopes for this bike, and need all the help I can get.  ???
Thanks in advance, and have a happy New Year....

Offline L.A.B.

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Re: 1972 Triumph T-120
« Reply #1 on: December 30, 2006, 12:07:38 AM »
Hello b737doc,

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There is a key hole on the handlebars, but I'm not sure if its for the fork lock,

If you mean there is a key slot in the upper yoke? Then it is probably the steering lock (recognisable due to there being no wires to/from it).  

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The headlight has a switch on it, but not sure what it does,

That is the lighting switch.


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1) Does the bike require an "ignition key".

Well it would originally have had an ignition switch (located in the R/H side panel on '72 models I think?) so yes it would have required an ignition key.

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2) Is approximately 4.0 ohms indicate a good coil?


You don't say which coil type you have, but 3-4 Ohms is probably OK.

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3) Exhaust clamps are there, but one is separated from cylinder head, nothing appears "broke" , is this good or bad?


More info please?

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4) The front struts are badly "pitted", is there a fix for this, or will they have to be replaced?

If you mean the fork stanchions (or 'tubes' US) then ideally = yes (or re-hard chromed) but it isn't necessary to replace the complete fork legs (if that is what you mean by 'struts')?

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5) The front wheel has a broken spoke, bad or good?

I'm sure you can work that one out for yourself!

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6) Brake pedal is on the left, shifter on right. Am I gonna go over the handlebars when I inadvertently down shift with the brake pedal?

Then don't do it!


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I need a seat, front and rear fenders, right side filter cover and triangular "fill in" panel, and fuel cap. How hard is it gonna be to get these parts?

Shouldn't be that difficult, although you don't bother to say where in the world you live so makes any supplier recommendation difficult.


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I found a small square electrical component with a little "squirrelly" coil coming out of it, what the heck is that?.

If it is rectangular rather than square then *probably* the flasher unit?

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10) Do you have to have a good battery for the plugs to fire?

You may get enough power from the alternator to fire the ignition when kick starting (provided everything is wired up correctly).

I suggest you get hold of a copy of the factory manual for your bike as soon as possible, and also a parts manual can be very useful.


L.A.B.

b737doc

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Re: 1972 Triumph T-120
« Reply #2 on: December 30, 2006, 02:02:04 AM »
Hey L.A.B.....thanks for the reply,,,I am in Hiram, Georgia, USA, a  suburb of Atlanta, Georgia. The exhaust pipe, where it goes into the head, just kinda "fell out". Theres nothing broke, I can't figure out what actually "locks" the pipe into the head. The other cylinder was good. When you say "flasher", does that mean that the bike has turn signals?  As for the "coil type", I have no idea. There's 2 cylindrical shaped parts that the plug wire comes out of, with 4 terminals, 2 on each, located underneath the seat.  The "struts", or the part the shiny chrome forks come out of, appears to be made of magnesium or aluminum, which is badly pitted.  Question 6 was an attempt at humor (sorry), and there's nowhere else to put a key....thanks again.

Offline L.A.B.

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Re: 1972 Triumph T-120
« Reply #3 on: December 30, 2006, 03:10:38 AM »
Quote
The exhaust pipe, where it goes into the head, just kinda "fell out". Theres nothing broke, I can't figure out what actually "locks" the pipe into the head.

I think you have a cylinder head with the 'push-in' exhaust pipes as your bike has engine number CG (March '72) 51184. This never was a very successful idea, and Triumph later went back to a 'push-over' stub type, the push-in heads can be converted if necessary I believe.


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When you say "flasher", does that mean that the bike has turn signals?

Originally yes for 1972.

 
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As for the "coil type", I have no idea. There's 2 cylindrical shaped parts that the plug wire comes out of, with 4 terminals, 2 on each, located underneath the seat.

Standard Lucas coils should have the coil type stamped on the coil base?

 
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The "struts", or the part the shiny chrome forks come out of, appears to be made of magnesium or aluminum, which is badly pitted.

So, it's the 'sliders' then. It should be possible to clean (and polish) them up if the pitting isn't too severe. They will be made of aluminium (aluminum) nothing as exotic as magnesium (not for original parts anyway) replacements should be available.

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Question 6 was an attempt at humor (sorry),

My answer also!!


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and there's nowhere else to put a key....thanks again.

It sounds as if the whole thing needs a good going over so that manual will be necessary.
L.A.B.

b737doc

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Re: 1972 Triumph T-120
« Reply #4 on: January 06, 2007, 08:09:08 PM »
Bike now stripped to the frame, frame being chemically stripped, will be ready on Friday (01-02) at $82. Engine cleaned up NICELY with "greased lightning",  Front and rear rims de-spoked, can re-plate rear at $100, Front rim will cost me $144. Spoke kits around $80, and I will attempt re-lacing them on my own.  Met "Ian", at Georgia cycle depot, EXTREMELY nice guy, has everything I need, and quite an impressive operation, and has ALOT of confidence in me.  Part time job dried up for now, will have to wait for more money.....