Which electric start for a MK2?

The Alton system has been around for about eight years now and has had subtle updates to make it a good system today - it is intended for bikes that are to retain their existing triplex primary drive. The cNw system is a more recent development of a somewhat more sophisticated design. Both spin the engine via the alternator-side of the crankshaft. Due to the width of the original triplex primary chain there is insufficient space to allow for the sprag clutch to be added to the crankshaft and still retain the original Lucas alternator thus  Alton provide a new 'slimline' alternator is supplied with the kit. In some cases this may be seen as a retrograde step - particularly if the bike has a three-phase or high-power alternator already. The drive from the starter motor to the sprag includes a chain section. Disengagement of the starter after start-up is totally reliant on the sprag. The Alton system can, with some modifications be fitted to Commandos with belt drive. The forthcoming December Roadholder has an article about this very subject.

The cNw system is somewhat more sophisticated. The kit includes a belt-drive system which is narrower than the triplex chain system and allows retention of the existing Lucas alternator (of any type) - it also negates the need for primary chaincase oil and the possibility of leaks etc.. The drive from the starter motor to the crank is all-gear. The system deploys a sprag clutch as per the Alton but also includes a 'Bendix'-type disengagement stage whereby the starter motor pinion is withdrawn from the drive stage as soon as the engine starts.

Both systems will hit your bank balance - the cNw system more so. There are a few suppliers of the Alton kit in the UK but I think the nearest cNw supplier is in the Netherlands thus carriage (and possibly duty) will be pricey. Suffice to say that both kits spin-up the Commando engines with ease (unlike the original Mk.III starter).

I've just fitted an Alton kit to my 72 Combat Commando which already had a 32mm belt drive. The process for me was not  plug and play as the kit would not fit with the wide belt. I had to turn down the front belt pulley to accept a 25mm belt, fit a new keeper plate for that pulley and also as described in the Alton Belt drive notes turn down the supplied spacer between the front pulley and sprag clutch. Access to a lathe and drilling machine was necessary for my conversion.

I have lots of images of the fitting if people want to see the process.

Suffice to say, as stated by Mark, it turns the engine with ease.

Nigel

Ace Classics are listed as Alton distributors (& fitters).

http://www.aceclassics.com.au/

Based in Torquay, Victoria (a first for me I leave near Torquay, Devon, UK)!

Andy