1943 triumph 3hw identification

[wdbikemad]

The same box (with different ratios) was used in most Triumph's up to 1962-ish when unit construction came in......

 

Incidentally, the Trumpet box is in reverse to most other WD boxes.......you go up-for-up, and down-for-down.....:-D

[Stefano]

Actually, the 3HW box is quite a different beast to the ones used on later Triumphs (1950 on). The layshaft on the earlier box is completely different and is a sort of semi floating affair running on much smaller (iron) bushes than the bronze ones (or needle rollers) used later. Actually, there are very few parts that are interchangable between the early and late boxes (mainshaft bearings, 4th gear mainshaft bushes - need shortening though, selector rod and possibly camplate, most kickstart and preselector bits), which is a bit of a pain because that means that parts availability for the early boxes has pretty much dried up. However, unless something really horrible has happened to the gears these boxes can usually be brought back to life without any massive difficulty. The mainshaft can usually be reclaimed where the 4th gear bushes wear it down by hard chroming and grinding back to size, ditto with the layshaft, although it's probably better to leave this just a tad oversize and then ream out the floating bushes to suit, since it's years since I've seen any of these for sale.

On another note, it's surprising to think that the later gearbox lasted pretty much unchanged all the way to 1968 if you exclude the speedometer drive gear on the layshaft (a rubbish idea if ever there was one - thank the sprung hub for that particular wheeze), not that that makes much difference anymore because parts for these also seem to be in ever shorter supply - a depressing thought...

Edited June 18, 2012 by Stefano

[wdbikemad]

Actually, the 3HW box is quite a different beast to the ones used on later Triumphs (1950 on). The layshaft on the earlier box is completely different and is a sort of semi floating affair running on much smaller (iron) bushes than the bronze ones (or needle rollers) used later. Actually, there are very few parts that are interchangable between the early and late boxes (mainshaft bearings, 4th gear mainshaft bushes - need shortening though, selector rod and possibly camplate, most kickstart and preselector bits), which is a bit of a pain because that means that parts availability for the early boxes has pretty much dried up. However, unless something really horrible has happened to the gears these boxes can usually be brought back to life without any massive difficulty. The mainshaft can usually be reclaimed where the 4th gear bushes wear it down by hard chroming and grinding back to size, ditto with the layshaft, although it's probably better to leave this just a tad oversize and then ream out the floating bushes to suit, since it's years since I've seen any of these for sale.

On another note, it's surprising to think that the later gearbox lasted pretty much unchanged all the way to 1968 if you exclude the speedometer drive gear on the layshaft (a rubbish idea if ever there was one - thank the sprung hub for that particular wheeze), not that that makes much difference anymore because parts for these also seem to be in ever shorter supply - a depressing thought...

 

I think I was referring to the overall design of the box, not necessarily interchangeability....:-D

[HotBed]

My hybrid has a 3SW oil tank I think 🤔 

Edited February 2, 2019 by HotBed

[morley88DR]

Ron

I have a 3SW from contract S5340 and I was interested in your information about the build date - TEC....  I have looked under my saddle but cannot find this.  I guess I might have to scrape off some paint but could you give more information on the location please?  Somewhere on the down-tube perhaps?

Thanks, Peter

[Ron]

Here it is on my 3HW. But it's not always there. Sometimes it's a repeat of the frame number and sometimes there is nothing. 

[morley88DR]

Thanks Ron.  Mine is in the same place but I never would have found it under the paint.  My bike was sold as army surplus and 'civilianised' with a coat of black paint. 

Many thanks for your help.

Peter

[RCB]

Hello, I am new here and was wondering what you could tell me about

Triumph Engine 3HW 44250, the underside of the cases are also stamped with 44250 and a 27,

Frame TL.53113, T.E.C. 1.45,

Contract Plate on rear fender.... Contract No. C/S 8886 Cat. REF. No. 21.  

Thank You for your time.

Ryan