From: Mr Paul A Owen <firstname.lastname@example.org>
Subject: Looking for an old friend
Had a 250cc Sunbeam reg YND 109 back in the70’s . Rebuilt & resprayed then parted company . Just wondering if she is still around.
Triumph Tina for sale Contact – Ken Heydon:- email@example.com
It’s not immediately apparent that there are 3 elements to this pivot system.
1 – Bush – Tight fit to swingarm
2 – Sleeve – Sliding fit inside bush
3 – Bolt – sloppy fit inside sleeve.
The sleeve is fractionally longer than the bush so that when the bolt is tightened the lugs on the frame trap the sleeve allowing it to pivot inside the bush.
Any slackness in the nut causes the pivot action to transfer to the bolt itself wearing it, the ends of the sleeve and the holes in the frame.
When reassembling it may be necessary to fettle the swing arm to allow the clamping action.
The sleeve has a grease transfer hole which is not in the centre so make sure it’s the right way round to align with the grease hole in the bolt.
The Tina/T10 Kickstart system is not a particularly well designed or robust piece of engineering and slipping, leading to being unable to start the engine, is a recurring theme which is made even worse because it’s impossible to do a bump start.
When figuring out how to make things work it’s necessary to understand the relationship of the many parts as they all need to work in perfect harmony and also that wear is cumulative.
In no particular order :-
Kickstart shaft and it’s bush in the swinging arm
Kickstart quadrant teeth
Kickstart ratchet – outer teeth and drive teeth
Kickstart ratchet bush and associated mainshaft wear. Probably the major culprit as any wear here allows the ratchet to cam out of contact with the inner drive pulley.
Inner drive pulley teeth
Main bearing wear
Wear in many of the components can be rapid as they collect a lot of dirt in normal use and constant dismantling and cleaning is needed to keep it all working.
Sometimes missed is a blocked mainshaft oilway which will lead to rapid wear of the centrifugal mechanism.
Incorrect reassembly of the components onto the mainshaft will contribute to lack of lubrication and rapid wear. (See associated post – Drive Pulley Reassembly and Adjustment)
Whatever you do don’t be tempted to take a file to any of the ratchet teeth – you will make things worse!
Attention to a good fit of the shafts, bushes and main bearings are the solution and may require the services of professional engineers.
In restoring any old machinery it always happens that the parts most needed are in the shortest supply.
I guess that very many kickstart ratchets and drive pulleys were replaced during the production years and that’s the reason they are now virtually unobtainable. What’s worse, with the ratchet gear I doubt whether any precision engineers would take on the job of tooling up and replicating it.
Useful extract from Hughie Hancox’s book “Tales of Triumph Motorcycles and the Meriden Factory” It describes how the Lucas 4CA contact breaker assembly should be set up, in much more detail than found in the official “Instruction Manual” Download from:- http://triumphscooters.co.uk/downloads/?did=169
Also relevant is this article on setting up the auto advance unit (AAU)
That electrolytic capacitor has to go – it’s the real weak point of any ignition system. First, read the following info on Brightspark Magnetos website:- http://www.brightsparkmagnetos.com/easycap/universal/index.htm
Next, buy the 220nF Universal EasyCap.
Lightly abrade the printed grid off the bottom. Assemble finished EasyCap – not forgetting to put a fibre insulating washer under the head of the fixing screw. Loctite the screw thread. Job Done – Easy.