14 hours ago, b40rt said:

12 years ago the Bosch system was still working as intended (generally) quite a few seemed to have deteriorated over the last few years. What's on yours Glen ?

I dont actually know, never had the flywheel case off yet ?

When a condenser (capacitor) is failing a good tell tale sign is the contact breaker faces show signs of bluing (dark blue) this is due to heat created by arcing. This arcing is more than you would get with a good condenser. The condenser stores electricity when the circuit is made, when the contacts begin to open the circuit is broken....unfortunately the split second the contacts begin to open there is inevitably some sparking and arcing, the condenser’s stored electrical energy provides a ‘back’ emf that helps damp the arcing and more importantly provides a boost to the ht coil. A lot of fledgling apprentices can attest to being given an electric belt from a charged condenser handed to them by a giggling work mate! So when the condenser fails you get misfiring and starting issues. Condensers for Bosch distributors are mounted on the outside of the distributor (on cars) and good old Lucas mounted the condenser inside the distributor....guess which one failed more often than not. Mounting the condenser on the frame ( usually under the tank area) allows the condenser to operate in a more friendly environment, ie less heat and vibration. The engine manufacturers installed the condenser in the flywheel area just for ease of packaging and less wire ( it all adds up to cost and time saving). Most any car type condenser will work on most any trials bike using CB ignition. Personally I use two mounted under the tank but shielded by the frame from exhaust heat and rising engine heat from the cylinder head. You should be able to view the contacts using a thin screwdriver to part the contacts and a torch to illuminate said contact faces, if the condenser is ok the faces will look light grey in colour, if blue then change the condenser.....iffy wiring connections excepted. Pay no more than £4-6.00 or go to a scrap yard and find a few engines with the distributor intact then strike a deal for the condenser’s say £2.00. Wiring...such fun?