classic motorcycle forum

Hi Goran,

The T15TT27 and 15TT32 are very similar carbies. Here's an extract from 1920s AMAC literature:

"T10TT25 This type was first used in the Isle of Man T.T. Races, 1925 and was afterwards put into general production for Sports machines, some being produced up till 1929 inclusive..."

So a sports bike from 1926 could be fitted with a T10TT25, but a 1926 TT bike would likely have a 10TT26.

The last update to the TT AMAC was the T10TT27 and this was used more-or-less unchanged up to about 1931. A 1932-model Norton, announced in say September 1931, might have specified a T10TT27 (while it was an AMAC carby, AMAC was part of AMAL by this time, so it would have had AMAL fuel bowls with AMAL on the lid), but later in the year they may have fitted the latest model AMAL 10TT32.

Your Model 40 sounds like a racy bike! The equivalent 350 Rudge was the "TT Replica" and it had a 10TT32 1 3/16" with twin fuel bowls. If your bike was built for racing, it probably started life with twin fuel bowls.

How about a photo?

Cheers

Leon

Hi Goran,

My racing Rudge uses an AMAL 10TT32 - just like the one you are looking for, but slightly larger size (1 5/32" bore on the 500, 1 3/32" on the 350). The carb is based on the AMAC T10TT of the 1920s.

The Type 15 AMAL - such as the 15TT32 - has bore size up to 1".

In 1932 and 1934 (there was a 10TT32 and a 10TT34, but I don't think there was a 10TT33) the carb was brass/bronze, with a bell mouth that screws onto an external thread in the body. In the later 1930s, the bodies were aluminium alloy, and the bell mouth was fitted with a bell mouth secured by a lock ring that screws into an internal thread.

Not that the TT series of carburettors has a jet block that goes in from the top, so it doesn't have the usual large gland nut holding the jet block in from underneath.

As well as different bore sizes, they come with stub or two different flange mount options (2" centres, or 2.2" centres), and a choice of single or twin fuel bowls at various angles.

They are hard to find, and expensive, but they are around. Here's a later 1930s version https://www.ebay.co.uk/itm/401472968043 - not absolutely correct but quite similar.

Good luck,

Leon

My very first powered two wheels was an Excelsior Auto byke, but unlike you I never got it running even though me and my brother spent hours pushing it up and down the garden!

My first foray into powered motoring was also with my brother, and an elderly Motorbecane moped that came from our uncle Jack. We got it running, and with a tank full of petrol managed to set it alight. It had a plastic petrol cap, and when this melted the burning fuel did a fair impression of a flame thrower from the mouth of the tank - the bike was on its side in the middle of the road by this stage. When the fire brigade came it was almost all over, but the memory of them throwing a bucket of water on the smoking heap lives on...

Leon

There are two areas that will make a two stroke "guaranteed gutless".

1. The bore, piston and rings have to be in good order. Bore wear is often worse in the area around the port openings, and this is often missed by people more used to four strokes which wear at the top.

2. Crank case seals.

If you've done/checked these two things, you're left with some possible fiddling with timing, plugs and jets. You may as well get the most power you can out of it, but even then don't expect too much. I ride an e-bike most days - 250W (1/3 h.p.) max - and it's great fun and exercise.

Enjoy!

Leon

B48159 is a very high frame number; it takes us all the way to 1929! So certainly wedge tank. For 1929, the B29 De Luxe (250) engines started at B 42108, frames started at B 47120. If you have an engine B43000-ish it probably goes with the frame.

Sausage tanks started in 1924 at engine number 1. The motors didn't change much, although I think the oil pump arrangement on the timing cover was one visible change.

Cheers

Leon

https://www.yesterdays.nl/product/velocette-1930-kss-350cc-1-cyl-ohc-2603/

Interesting to compare lugs, and even the battery platform. Not sure how long the twin front down tubes lasted - maybe 1933-4 or so.

Best for Christmas,

Leon

Nice frame, rotten photos! I think you'll find it's one of the road-going cammy Velocettes from the 1930s: http://www.velocetteowners.com/catalogues/cataloges/1930s_cat.html

Cheers

Leon

Yes John - I was thinking of you only yesterday when I saw this photo - from Rockhampton, Queensland, on ebay Australia. Must have been a hot bed of Chater Leas!

Cheers

Leon