BritBike Forum logo
BritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike Sponsor SteadfastCyclesBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorHepolite PistonsBritBike SponsorBritBike Sponsor
Upgrade to: Gold Membership | Premium Membership | Vendor Membership | Site Sponsor Membership
Words from our sponsors..
Vintage Motorcycle Auctioneers!
Vintage Motorcycle Auctioneers

CLICK HERE to see VIDEO
How the Electric Roller Starter works.

ORDER on eBay. CLICK HERE!
Buy your Electric Roller Starter here
ShoutChat Box
Comment Guidelines: Do post respectful and insightful comments.
Buy BritBike staff a coffee
Buy BritBike's staff a coffeeStill here since 1996 serving BritBike enthusiasts..
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Member Spotlight
Matthew Manton
Matthew Manton
Toronto
Posts: 538
Joined: April 2004
Show All Member Profiles 
Newest Members
Bill Walker, Phil McClusky, 1957 Road Rocket, Payne, Mysticbus
11018 Registered Users
Top Posters(30 Days)
franko 135
koan58 66
DavidP 63
Popular Topics(Views)
1,149,219 mail-order LSR
a word from..
Forum Statistics
Forums35
Topics68,949
Posts691,025
Members11,018
Most Online14,755
May 5th, 2019
Who's Online Now
68 registered members (998John), 2,630 guests, and 977 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Pre unit swing arm gearbox types #797476 02/03/20 11:33 pm
Joined: May 2012
Posts: 56
J
jimq Online Content OP
BritBike Forum member
OP Online Content
BritBike Forum member
J
Joined: May 2012
Posts: 56
Hi all.

I have a question today which i have tried answering for myself on google and have been surprised i was able to not easily able find a direct answer.

In Basic terms; what is the difference between a standard gearbox, a box marked T and a box marked T2.

Thanks in advance.
Jim.

Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK
British motorcycles on e-Bay North America
CLICK HERE to see VIDEO
How the Electric Roller Starter works.


ORDER on eBay. CLICK HERE!

Buy your Electric Roller Starter here
Re: Pre unit swing arm gearbox types [Re: jimq] #797477 02/03/20 11:57 pm
Joined: Sep 2001
Posts: 3,139
Gordo in Comox Online Content
BritBike Forum member
Online Content
BritBike Forum member
Joined: Sep 2001
Posts: 3,139
Jim: the standard box has bushing on the ends of the layshaft and where the mainshaft goes through the A gear (gear that the sprocket goes on). The T box has needle bearings on the layshaft and the T2 box has needle bearings on the layshaft and where the mainshaft goes starts to go through the A gear. I think there is still a bush for the outside of where the needles end on the mainshaft.

I assumed by standard you are not asking about the various ratios of the gears like STD.

Gordo

click to enlarge

Here is a shot of the parts page that shows both the bushings and needles for the layshaft

[Linked Image from i.postimg.cc]

This parts book page shows both types of A gears

[Linked Image from i.postimg.cc]

Last edited by Gordo in Comox; 02/04/20 12:21 am. Reason: photos added

The roadside repairs make for the best post ride stories.
Re: Pre unit swing arm gearbox types [Re: jimq] #797478 02/04/20 12:40 am
Joined: May 2012
Posts: 56
J
jimq Online Content OP
BritBike Forum member
OP Online Content
BritBike Forum member
J
Joined: May 2012
Posts: 56
Hi thanks for your reply Gordo.

Would that mean that a T box could effectively be made a T2 box by replacing the A gear.

Cheers.
Jim.

Re: Pre unit swing arm gearbox types [Re: jimq] #797480 02/04/20 12:49 am
Joined: Sep 2001
Posts: 3,139
Gordo in Comox Online Content
BritBike Forum member
Online Content
BritBike Forum member
Joined: Sep 2001
Posts: 3,139
Jim: I have no first hand knowledge but the mainshaft appears to be a bit different in the roller area looking at the diagrams I posted. I do know that the two layshafts are not the same size in area where the needles go..

Someone will know.

Gordo


The roadside repairs make for the best post ride stories.
Re: Pre unit swing arm gearbox types [Re: jimq] #797485 02/04/20 1:34 am
Joined: Nov 2011
Posts: 5,666
Magnetoman Online Content
BritBike Forum member
Online Content
BritBike Forum member
Joined: Nov 2011
Posts: 5,666
Originally Posted by jimq
Would that mean that a T box could effectively be made a T2 box by replacing the A gear.
No. The A gears for the T2 gearboxes have a needle bearing in one half and a bush in the other half, and to accommodate this the mainshaft for the SCT2/RRT2 has a step in it to provide the somewhat different clearances required.

See also the following for a fairly detailed description of the internals:

http://www.britbike.com/forums/ubbt...e-1957-bsa-spitfire-scrambler#Post757258

Last edited by Magnetoman; 02/04/20 1:48 am. Reason: clarified text
Re: Pre unit swing arm gearbox types [Re: Magnetoman] #797491 02/04/20 3:09 am
Joined: May 2012
Posts: 56
J
jimq Online Content OP
BritBike Forum member
OP Online Content
BritBike Forum member
J
Joined: May 2012
Posts: 56
Alright cheers Magnetoman.

that could be my evenings reading.


Moderated by  Allan Gill, Jon W. Whitley 

Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | DVD- Manuals & Parts books
Upgrade to: Gold Membership | Premium Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.7.3