Engine Plates , Norton wideline twin, Norton laydown, Triumph T110 pre unit

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Good evening,

i discussed with my mate if a Norton laydown gearbox and a Triumph T110 engine fit together in a wideline twin frame. Does that work? And where can i get matching engine plates?


regards
Stefan
 

grandpaul

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Those plates are not readily available unless Dave Degens (Dresda) makes them.

What you have to do is set the engine with transmission and primary in the frame with various blocks of wood in place to support them, and arrange them to:
(1) the closest reasonable spacing of the swingarm pivot point to the transmission mainshaft, and
(2) the lowest CG you can get that allows a reasonable routing path for the exhaust (if standard downswept pipes).
You can use stiff (coat hangar) wire to support the bits, as well.

Once everything looks good, carefully measure your critical mounting point dimensions and sketch them onto a clean sheet of butcher paper, then draft the potential outlines for the front and rear mounts. Cut out the mounts with scissors and test-fit them in place, adjust and re-sketch as required. Once they seem to fit, transfer the patterns to thin (1/4") plywood, and test fit. Once you are sure of the patterns, transfer them to 5/16" 6061 aluminum plate readily available at Speedy Metals If you need any spacers, Speedy also sells 6061 alloy tube stock that you can cut to length.

If you don't have a band saw, you can cut this with a jigsaw or farm it out to a local tradesman. You can also do rough cuts with a metal cutting blade in a circular saw or angle grinder, then finish cuts with hacksaw or jigsaw. All edges can be filed them sanded smooth.

All of the hardware you'll need can be found at Fastenal.

Order enough materials for two sets, and put the second set on e-bay to recoup your costs. You can also sell patterns...
 
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Eddie,
i already have a laydown and it is the matching box for my 1954 frame.

Grandpaul,
thank you for your advice. But i still hope to get a layout or already produced
plates.
 

Fast Eddie

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Steko, it’s your bike my friend, so it’s your choice to do with what you please...

But IMHO, that’s a lot of work to go to in order fit something you have to hand that offers no actual benefit and it would be easier to get another box and use ‘normal’ engine plates.

I would imagine the lay down box to be less robust than the later Norton boxes too. Triumph boxes are also, generally, very good and give a cheap way of getting a 5 speed cluster.
 
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You can probably install the gearbox in alloy plates meant for a different one, with spacers, drilling and possibly milling.

Or you may be able to weld the sawn-off rear portion of original steel Norton plates to the front part of steel Triumph plates. Getting the length right will be fiddly, unless you can draw an accurate pattern of a Triumph crankcase in a Norton frame.

Or you could make new alloy plates, using a pattern made by laying a steel Norton plate on top of a Triton plate with the rear frame stud holes lined up.

I haven’t mentioned chain lines, have I!
 

grandpaul

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I also have two different spare Triumph pre-unit gearboxes and a bunch of 5-speed parts...
 
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Accoring to an old issue of M C M , if you throw the Triumph engine In , on the Norton Std Plates , Rear . you drill a new top hole .

The motor leans forward a bit .

a stick under the engine so ' free play ' is neutral - whack up patterns for front plates .

If youve a drill press & a vice , you should be able to replicate in aluminum .

If you dont want it leaning forward , redrill ALL the rear engine holes .
 
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I usually make my own engine plates. With a pre-unit Triumph motor in a featherbed frame, it is important to get the motor as far forward as possible, with the gearbox well back. The centre of the gearbox mainshaft should end up about 1/4" higher than the lime between the crank centre and the rear axle centre, so the rear of the bike tends to rise as you accelerate, rather than squat - the squat then becomes the result of the acceleration and is opposed by the chain pull. I usually start out by positioning the motor and gearbox in the frame on blocks, then using scissors and cardboard. I use 8mm aluminium plate and a jigsaw and cut the plates by hand. I use a belt sander to smooth the edges, but usually bolt the pairs of plates together when I am doing it. To get the holes in the right place, I usually turn a point on a piece of 3/8" round and use it as a marking punch. Always drill the pairs of plates when they are bolted together. And it is often better to drill the holes less than 3/8" and ream them to size. The only part which presents any difficulty is getting the gearbox height correct, so drill the holes and cut the slots last, then trim the cut-out for the box. You need a gearbox adjuster on both sides and the slots should be curved.

I think you will find that most of the readily available engine plates will put the motor about an inch too far back - it affects the handling. The front engine mount on the motor should touch the front frame mounts, or you will find the bike feeling airey in high speed corners. Making the plates is easy after you have done it once. I taught myself to do it when I was about 18 years of age. You should have plenty of room to fit your lay-down gearbox. Featherbed frames are huge compared to what happens when you try to use a BSA A10 frame to make a Tribsa - that gets fiddley.

Like anything, you start at the beginning and work to the end The first guy who ever did it, was not a genius.
 
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Seeing we're being awkward ,


this is the swine to use ,

RIDGID , Pre unit Alternator , rare as . cop Bike ?? .

Dunno if the ridgid gear case is mandatory , butitllget the Gearbox Sprocket RIGHT BACK ,
and the crank case / crank shaft , right down low & forward . Even goina slimline .
 
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Many years ago when I was a kid, I had a 1958 Thunderbird with the alternator, which I bought from a cop. The cops had similar bikes with radios, sirens and more lights. We use to play a lot with pre-unit Triumphs. I never actually saw a cop bike with both alternator and generator, but I believe they existed. The friend who discussed them with me was very reliable. In those days we could buy used cop bikes from auctions. I would never buy one, because they'd usually been mistreated - especially the gear boxes. The Thunderbird I had, was involved in a fatality. The tank had hit a brick wall.
There is another thing about those pre-unit models - on race bikes the rev counter drive used to fit in place of the generator. Some 650 models had a rev-counter drive in the same place as unit 650s, and could also have the generator fitted.
 
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In the Aus classic bike mag , theres a picture ( In one issue , dont ask me which ) of a ORANGE TRITON .

Says something like Joe Blogs bike , recently sold etc .

Was in Sydney in 81 , at the Dudes Shop , where Rod Price worked.

Was a Slimline 800 8 stud , dual dunstall disc . Full Fairing .
The dude said it was timed at 159 mph down Conrod , on methanol .
He had had the barrels cast , and said nobody believed it was 800 cc .
Runs dual 32 mm dellortto 's .

One of these Aussies should recall the bloke . Mightve been in Belmain .
Had a Chinese wife .Nice clean & tidy race bike . n top of the thing
( mezzanine ) at the rear of the smallish ( 20 bike ? ) shop .
 
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The Carter Triton from Victoria was orange and would have been ridden at Bathurst by Jeff Curley. You would not want to be doing that. Most Tritons had drum front brakes and the end of Conrod Straight is extremely fast with very poor run-off at Murray's Corner. That stuff looks good, if you are not on the bike, but a mate of mine scared himself shitless there and another one got killed.
 
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There was no such thing as a standard police model, at least not in the UK. Each police force had its own spec (or specs) depending on the role that was required, fast patrol work, slow escort duty etc. However, there were some fairly common features such as a single seat (but not always), higher power alternator.

If memory serves, the TR6P was exported in 67 to replace the Thunderbird. I think that was the first year. As a stock bike it would have had the larger tank, single seat and all white tinware. They look pretty cool.

Take a look here under Saint;

http://www.classicbike.biz/Triumph/Mags/Magazines.htm
 
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The Saint had a light crankshaft, so did not perform so well as other Triumph 650s. But a cop would not know the difference. Our Victoria Police had mainly the BSA Gold Flash. We used to encounter them at Calder Raceway when we were practising. They used to get upset when the guys blitzed them going into corners, when they were training. The joke was that most of us were only racing because we'd been booked by the bastards. I think Bernard is correct, the police bikes seemed to have been ordered from factories as specials.
 
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