Scottish engine plates

[fioand]

I have just drawn out a template to manufacture new engine plates for my 1960 Scottish. Dimensions taken from drawing supplied by Rob.
On dropping my old engine plates on top of the template it appears the engine/gearbox mountings are 25mm forward and 10mm lower than as shown on the drawing.
I am sure I read on another thread that the front exhaust pipe differs between the TA and TC.
This could be the reason for the front exhaust pipe having to be adjusted to mate with the Silencer when I first got the bike.
Could anyone comment on this for me .

[John Wakefield]

Scottish engine plates

The engine plates were changed in 1961 with the TD series. These resulted in the engine being 1/2 inch lower & 7/8 inch further forward. (Info C&W Greeves book page 56)

[fioand]

Thanks for reply.
The dimension stated confirm dimensions on plates fitted to the bike. The plates fitted are an aluminium aftermarket item (soft and in poor condition).
Rob has provided the correct drawings for the bike (1960 frame no. 60/1144). It is looking like a previous owner has fitted a later type plate
Rob. If you read this, I would be interested to see the profile for the later TD plates as I intend to manufacture some from 6082 grade alloy.

[Rob]

Right, here is the TD engine plate for comparison.

I would be interested to hear the conclusion to this one!

[Phil Hyde]

Engine plates

A few thoughts on aluminium engine plates.

Good to hear you are going to use 6082 aluminium plate. T6 spec in a half hard state will be spot on. 6mm thickness should be ideal, however, you could try 5mm.

Before committing to metal confirm your final shape with plywood templates. A whole lot cheaper than metal.

When it comes to cutting out your plates stick two plates together with double sided tape. Drill your holes and finish (filing, linishing, etc) the plates before separating.

Hope this helps

[fioand]

After an afternoon in the garage I have determined the following-
It appears I have on my machine a pair of hybrid engine plates. These have been made to all the dimensions from the TC drawing but the engine mounting lug holes have been moved towards the headstock by 25mm and lowered by 10mm
The difference between the TC drawings and the TC is as follows:-
The horizontal distance between the bottom hole on the alloy headstock casting and the Swinging Arm pivot is reduced by 7/8"
The vertical distance from the swing arm pivot to the gearbox mounting lug is increased by 5/32"
This effectivly moves the engine forwards by 7/8" and down by 5/32"
All other dimensions remain the same excepting for the footrest assembly holes, which were moved rearwards by 15/16" and raised by 3/8"

Rob. I could do with the outline drawings B640. And B987-A if possible.
Phil. Thanks for your thoughts. 8602-t6 half hard is exactly what i have.

After spending the afternoon working in 1/64ths and 1/32nds I now need a drink! I am 70 now and do not know how we managed to work in Imperial measurement, after spending the last 50 years working in metric
Kevin
Phil

[fioand]

8602 should read 6082

[Rob]

....ah, here we have a problem. There are no 'flat form' drawings in the archives. The only way round the situation is to expand the drawing on a photocopier until the dimensions are to scale. Sorry about that.

Sounds to me as though someone has had a go at shortening the wheelbase and steepening the head angle if the beam to swinging arm distance is shorter. I know people have messed about with this in the past.

Phil - could you explain this 6082 and T6 business please, possibly on a new thread? I've heard of it before but never followed it. Ta!

[fioand]

Thanks Rob. I think I can take a guess at the profile,and develop it on fitting

I have just read in Colins book ( page 92) that the TD model got new engine plates to bring the engine forward by 1" ,changing the weight distribution.
The TD model also got the updated frame which gave a shorter wheelbase.
This could explain the shorter beam to swinging arm dimension.

[Rob]

So, is your frame a TCS or TDS?

Must admit, I've never got into this much detail with dimensions of Scottish's before!

[fioand]

The frame is a TC ( 197 9E ).
Length of engine plates are correct for TC but engine holes have been moved forward as on TD.
Angle of beam holes stays the same on TC and TD plates, 13 degrees, so the headstock must have stayed the same unless the casting was changed.
Thanks for all response!

[greeves246]

engine plates

Hi if your going to make TAS Plates i would be interested

gary

[fioand]

At the moment I have the engine sitting in a pair of 6mm MDF engine plates that I have made to use as a template
I have partially reassembled the unpainted frame to check that the exhaust is still able to be assembled. The frame is complete, minus swing arm and forks, and the engine and exhaust are mounted. The strength of the MDF plates is quite astonishing when they become an integral part of the assembly!
Plates have been made to original dimensions provided by Rob

Greeves 246. I wiil pm you when i get the alloy ones finished and side stand bosses welded in

[Brian Thompson]

The Greeves MDF Model....!

At the moment I have the engine sitting in a pair of 6mm MDF engine plates.....

Ahh yes...the mythical Greeves MDF, even rarer than the fabled Gauntlet MOD prototype....

Only one example is known to survive, and due to the lack of reliable pics/info available, even within the GRA, it's owner and restorer, the legendary Bavarian 'chippy Otto Von Klusterbuck, had to use considerable 'artistic licence' during the rebuild.....

Glad you're making progress Fioand, and best wishes for the rest of your rebuild.

Brian.

[dave higgins]

No myth Brian, the greeves MDF was supplied to certain dealers in the uk in kit form, or as we now know it...FLATPACK... at first sales looked promising, but slumped soon after when hoards of customers complained of opening the box only to find half the parts missing....