Triumph pre unit gearbox

Fast Eddie said:
I’d your box was built for racing by Mr Pick it’ll most likely have his semi close ratio conversion and will be a really sweet box.

As you have an electric leg, my advice would be to leave it be and fit it as is.
Click to expand...
Yep it is close ratio
I've ordered a complete pre unit box from eBay,so I'm awaiting it's arrival
I will rob the kick start ratchet assembly and inner and outer cases from it
Plus I want to practice welding stiffeners on the top of the main case without distortion
I don't actually use the Kickstarter but I'd like one fitted as backup
I did manage to kickstart it this morning
It's never been a brilliant starter with the single TM
The best it starts is with the twin amals
 
Responding to Flatspot's post with the Trident pix: no pre unit expert so I thought I was looking at an A10 with an
implanted T150 engine. If that is indeed a non unit Triumph box perhaps they are superior to the BSA box as is
the Trident engine to any of the twins. But one has to wonder what the increased weight and power does to the frame and therefore the handling. I do like the fun of transplants but the plumber's nightmare of remote fuel bowl
doesn't look like fun.
 
Onder said:
Responding to Flatspot's post with the Trident pix: no pre unit expert so I thought I was looking at an A10 with an
implanted T150 engine. If that is indeed a non unit Triumph box perhaps they are superior to the BSA box as is
the Trident engine to any of the twins. But one has to wonder what the increased weight and power does to the frame and therefore the handling. I do like the fun of transplants but the plumber's nightmare of remote fuel bowl
doesn't look like fun.
Click to expand...
A Triumph gearbox is good enough, as is a BSA gearbox.

A Triumph gearbox can be more readily converted to 5-speed though.

The triples would have been better bikes than the twins, had they been made properly.
 
<The triples would have been better bikes than the twins, had they been made properly.>

How well I know. :-(
 
The THING with the P. U. Box is the LOWER BOLT FIT . Really a reamed custom ' stud ' would be better , or a steel sleeve . But thatd thin the case & be thin walled .


ovalised / un tight fit isnt unusual ( if its been run loose ) . DUAL top adjusters are mandatory .

The Triumph box is rather sturdy . Unless your a stunt rider or evel knevel , thered be little point in attacking the case with a welder .
 
Matt Spencer said:
The THING with the P. U. Box is the LOWER BOLT FIT . Really a reamed custom ' stud ' would be better , or a steel sleeve . But thatd thin the case & be thin walled .


ovalised / un tight fit isnt unusual ( if its been run loose ) . DUAL top adjusters are mandatory .

The Triumph box is rather sturdy . Unless your a stunt rider or evel knevel , thered be little point in attacking the case with a welder .
Click to expand...
I've seen quite a few with the top mount ripped off
Not seen a problem with the bottom mount,apart from wear when left loose
Top mount will have twin adjuster's
 
The shock load from turkeys not keeping it all tight might hammer it loose , but how the # would you ' tourque ' it outta the case ,
as in tear the top lug out . Id think it slamming back and forth , however microscopically , would ' impact drive ' a crack into it to start .
Then tear free .

If it aint broke dont ' fix ' it . Could get the dye penetrant out though , couldnt do any harm . Unless its ' core shift ' in the casting .
Assume the main cases are ' the same ' thickness . Is the ridgid case thinner and breaks . Are the slick shift or ' sports ' cases thicker .

Theyve run 160 horse thru them , on dragstrips & the salt lakes - so I cant see a inherant weakness . Theres a lot of people ' doing it good '
and degrading old stuff now . Makes ya weep wot keen young men & gals do , in the name of ' progess ' . Destroying original factory quality
permanantly .

These turkeys cant do panelwork apparently . That Quaterpanel fit is a bit technical . Bound to be a bodge job - fast & loose - where all that
needs replacing is the lower rear . How unusual .


They dont realise the Factory mightve had a few more Brains than theyve manadged to get .


Seeing its a monocoque , that there panels doin a bit of work - its not a toy . Sorry about the tirade - but yer gether drift .
IF its bolted in properly , it should stay together .
Another THING . Take Up . On a THING , You ' Feather ' the CLUTCH , not ' Drop It ' . from outta nowhere . As SITTING THERE ,
Its Home bbbbbbefore the slack there , and in the gearbox , and diff , are taken up . So Fully Engaged as it all ' hits the stops ' .
Usually , its the spider gears that go . On one of those contraptions . But you get the drift . Hondas were famous ? for drive line slack .

Failure to account for that , and there should be naff all , on a TRIUMPH . would get the shock loading into play .
combined with a ' Show Quality ' gearbox fit . KAPOW ' Sheet - Ive got so much horsepower I blew my gearbox .

Er , Right .
 
Matt Spencer said:
The shock load from turkeys not keeping it all tight might hammer it loose , but how the # would you ' tourque ' it outta the case ,
as in tear the top lug out . Id think it slamming back and forth , however microscopically , would ' impact drive ' a crack into it to start .
Then tear free .

If it aint broke dont ' fix ' it . Could get the dye penetrant out though , couldnt do any harm . Unless its ' core shift ' in the casting .
Assume the main cases are ' the same ' thickness . Is the ridgid case thinner and breaks . Are the slick shift or ' sports ' cases thicker .

Theyve run 160 horse thru them , on dragstrips & the salt lakes - so I cant see a inherant weakness . Theres a lot of people ' doing it good '
and degrading old stuff now . Makes ya weep wot keen young men & gals do , in the name of ' progess ' . Destroying original factory quality
permanantly .

These turkeys cant do panelwork apparently . That Quaterpanel fit is a bit technical . Bound to be a bodge job - fast & loose - where all that
needs replacing is the lower rear . How unusual .


They dont realise the Factory mightve had a few more Brains than theyve manadged to get .


Seeing its a monocoque , that there panels doin a bit of work - its not a toy . Sorry about the tirade - but yer gether drift .
IF its bolted in properly , it should stay together .
Another THING . Take Up . On a THING , You ' Feather ' the CLUTCH , not ' Drop It ' . from outta nowhere . As SITTING THERE ,
Its Home bbbbbbefore the slack there , and in the gearbox , and diff , are taken up . So Fully Engaged as it all ' hits the stops ' .
Usually , its the spider gears that go . On one of those contraptions . But you get the drift . Hondas were famous ? for drive line slack .

Failure to account for that , and there should be naff all , on a TRIUMPH . would get the shock loading into play .
combined with a ' Show Quality ' gearbox fit . KAPOW ' Sheet - Ive got so much horsepower I blew my gearbox .

Er , Right .
Click to expand...

The way I look at it I wouldn't have thought Dave Nourish would have bothered making and selling heavy duty replacement gearbox shells for no reason?
 
Yep ; some people can manadge to wreck anything .
M/Cycle cop booted nutter , crunching EVERY shift , on the Commando . Virtually impossable . ( Theyre the W W 1 knee high lace ups )

The TRIUMPH Clutch , I think , is ' slower ' to free . Therefore the tecnique under monumentous output , requires considerable attention .
Most people are incapable of it .

they just force it through .

Volia ! a good market for reinforced gear cases . The brute force & ignorance technique , combined with inadequate fastening , or a grossly forced shift-
Where it dosnt ' engage ' but the teeth toes meet - produces results that were never intended .

Past the 7.800 / 8.100 , not many would ' catch' the shift . Again - a non unit has differant dynamics there , somewhat .
 

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