Triton T120R pre-unit engine

I don’t have a detailed picture of the timing side, just this one I’ve zoomed in on, and I ‘think’ it maybe big bearing, it is hard to tell from this angle. We’ll find out sometime
Triton T120R pre-unit engine
 
Incidentally, the TR6 cases I have are also ‘60/‘61 and they are big bearing. I always thought ‘big bearing’ was the option on T100 pre unit motors.
 
Flatspot said:
Incidentally, the TR6 cases I have are also ‘60/‘61 and they are big bearing. I always thought ‘big bearing’ was the option on T100 pre unit motors.
Click to expand...
I believe all pre unit twins went to big bearing in 1955
Someone will know
 
baz said:
I believe all pre unit twins went to big bearing in 1955
Someone will know
Click to expand...
I think you're right. Now upon prompting, I'm remembering that I was after a big bearing case for a generator on the timing side, which was only a year or two.
 
INDEED . You can see the ' retainer ' around the BIG BEARING there under the Timing Cover . 55 wastheyear .foremon.

Triton T120R pre-unit engine


THESE ' square ' Crankshafts . ( the CRANK WEBS are pear shaped ! the FLYWHEEL is square ! )
are wotthey fit in THUXTON , and presumeably T 1`20 T T .
Which is why the 67 is a Cowboy Cickle .

Theyre a bit crankey if your not a throttle merchant . But not to worry, theyll make one out of you .

Wouldnt pay through the teeth . Wouldnt really like past first undersize . WOULD Crack Test before any loot spent on machineing .

The Timing Cover oilway bush . The bearings'll be shot when its worn . a Oil Seal isnt the same . Nicked its trash .

Dont BANG or nick the rods . Coverem . Keep Up Higher on a shelf . DONT TOSS ANYTHING , like Rod Bolts & Nuts .

( inspect under strong light with a good eyeglass -m all the ' tricky bits ' .)

Can we see inside your head . The CHAMBERS . Valve Seats particularly . Be nice to know the recession diameter ( I.D. where its sunk . )

Std CAMS with cut down 1 3/4 pipes , just get withit with Std Gear ratios , if you dont mind shifting & use set throttle. Like. Man .
 

Triton T120R pre-unit engine


A general no no is High comp. ( 11 / 12 : 1 as the DOME masks the flow & THINGS . 9 or 9.5 .
The riginal 8.5 is fine , and gives a more flexable motor .

Triton T120R pre-unit engine


AND there were ' Works Tooned ' fruxtons , Cobber . Too .

Triton T120R pre-unit engine
Triton T120R pre-unit engine


BUT money money money . AND . unless you know bettern THEM .( Triumph Engineering . they built one or two . ) Dont Muck With It .

CRACK TEST CRANK . Meticulously CLEAN all componentry .

CLEAR & check oilways . Make Sure PUMPS UNWORN .

Ball race main bearings ! allow the Crank to ' Whip ' ( Apparently the 67 whips best . hondas and the like . )
Whereas ROLLERS are more drag , and likely the ridgidity harshns vibes & slows output . tho last longer .

Dunno if anyones put Superblends ( Barreled rollers ) inem .

AS IT WAS DONE , isnt too bad . But you see the Cranks RIGHT . ditther spin , rotate , gap check & concisitry
generally getting to know it . Dont Drop It . If you do if you dont throw your FOOT under it to soften the fall
you dont deserve it !

Well , thats about that , for that , then . For Now .

Actly , Degdens ' soft ' motor , with the 2 - 1 , will go pretty good , and wont TIRE the RIDER . Like a real fast one .

Triton T120R pre-unit engine


But THE PIPE WOULD RUB ,( Std Pipe ) which is why MANXes went to ' Hi Pipe ' set up .
The Trigonic KR 76 tyres'd letem go way over , on a track .

THINKING laST NIGHT , REPEAT CYCLE . FIFTY HORSE . Manx . t 120 . T 100 . 60 at best.

WHAT a Triton is is a Featherbed with 50 or sixty Horse . Like a Manx .

So just dither about and see theres No Faults . Theres no point throwing dollar bills at it .
It'll devour them of its own accord . So keep them well hidden before it gets a taste for it .

🙁









Triton T120R pre-unit engine
 
Flatspot said:
Not me. Years ago I would not have hesitated to rip it apart. However, although I have amassed a large number of tools over the years I don’t have things such as cam drive pullers - and I no longer have any expertise on an old Triumph engine. As such, I have taken the motor alone to a local highly recommended engineer who specialises in Triumphs.

My money on it is it’s a 650, and I’m happy with that, it was what I was expecting prior to actually doing the deal.

His brief is to strip it totally and advise me what requires doing to it. He has suggested that I replace the conrods with billet ones as we have no idea what has happened over the years, do we trust 60+ year old rods? - that will give me a spare set to go along with a spare set of TR6 cases, crank, cams, oil pump etc.etc. If I decide to sell off some ‘stuff’ to finance the build.

We won’t be looking to change cams for more power or anything else like that. It’s not needed, reliability is king.

I’ve asked him to ship the magneto off to a local specialist for refurbishing, condenser, points, remagnetise and such like. I know I could go for an electronic ignition conversion but it’s not how I want this to go back together.

What I will likely be doing is to strip and check the gearbox, and give it a good clean externally, new seals and bearings.
Click to expand...
I agree, nowt wrong wi’ a good mag !

Also nowt wrong with a sweetly put together 650.
 
My mate has a penchant for Thruxton Bonnevilles, he has rather a lot of them, easily double figures and all of them immaculate (I think I hate him 😂 )
 
Matt Spencer said:

Triton T120R pre-unit engine


A general no no is High comp. ( 11 / 12 : 1 as the DOME masks the flow & THINGS . 9 or 9.5 .
The riginal 8.5 is fine , and gives a more flexable motor .

CRACK TEST CRANK . Meticulously CLEAN all componentry .

CLEAR & check oilways . Make Sure PUMPS UNWORN .

Ball race main bearings ! allow the Crank to ' Whip ' ( Apparently the 67 whips best . hondas and the like . )
Whereas ROLLERS are more drag , and likely the ridgidity harshns vibes & slows output . tho last longer .

Dunno if anyones put Superblends ( Barreled rollers ) inem .

AS IT WAS DONE , isnt too bad . But you see the Cranks RIGHT . ditther spin , rotate , gap check & concisitry
generally getting to know it . Dont Drop It . If you do if you dont throw your FOOT under it to soften the fall
you dont deserve it !

Well , thats about that , for that , then . For Now .

Actly , Degdens ' soft ' motor , with the 2 - 1 , will go pretty good , and wont TIRE the RIDER . Like a real fast one .

But THE PIPE WOULD RUB ,( Std Pipe ) which is why MANXes went to ' Hi Pipe ' set up .
The Trigonic KR 76 tyres'd letem go way over , on a track .

THINKING laST NIGHT , REPEAT CYCLE . FIFTY HORSE . Manx . t 120 . T 100 . 60 at best.

WHAT a Triton is is a Featherbed with 50 or sixty Horse . Like a Manx .

So just dither about and see theres No Faults . Theres no point throwing dollar bills at it .
It'll devour them of its own accord . So keep them well hidden before it gets a taste for it .


EXCELLENT POST!
Click to expand...
 
con rods: if you are doing limited mileage, they are probably fine to re-use after suitable inspection. I would suggest a file with plenty of notes before you go away.
 
Founda pitcha offa Long Chaincase - Triton . To throw av thingo in the wotsit .

Triton T120R pre-unit engine
Triton T120R pre-unit engine


This means you can access the oil feed pipe easier . ! :p
 

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