Workshop Session Saturday August 10th 2024

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With the holiday season upon us it was a relatively quiet session. However the following work went on...


Jiailing 125.

The Jialing has been in pieces for some time now as club members work to restore the look of what was a rather tired looking old Chinese 125 and make it look it look like a half decent attempt at a trails bike.  Amongst the pile of components awaiting re-finishing are the front fork sliders, steering head upper and lower yokes, handlebars and the external finish of the engine itself.  Don and Andy have spent a good deal of time working to repaint the fuel tank.  Today Don worked on rubbng down the blue paint finish to remove a couple of runs ready for the final top coat.




Kawasaki Z250.

1st time attendee Jon helped Graham who was working to tidy up the bike's rather messy wiring. During the previous session Graham had fitted a brand new voltage rectifier/regulator to the bike.  The original item having been the cause of several blown fuses whilst we were working to get the bike running at this year's Llandovery Bike Weekend because it had shorted out internally. Jon's assistance keeping the wiring still and offering suggestions as to what to do was most gratefully receieved.  Once the wiring was tidied Graham spun the engine over with the spark plugs out, to make sure their was a good spark on both cylinders.  There wasn't.  There was a good spark on the left had cylinder  but next to nothing on the right hand side. This was most peculiar as the coils were brand new and the bike had started and ticked over just fine at Llandovery. Having checked that  the points cover wasn't shorting the wire to  the contact points, Graham and Jon checked through the wiring but everything seemed OK.  Eventually Graham took the bike outside, added some fuel in a temporary tank and started the bike up.  It was definately only running on the left hand cylinder.  Pulling  the right hand spark plug cap off made no difference to the way the engine was running. Having re-checked the wiring with Andy, Graham suggested we should try another coil.  Once one of the bike's original coils was located and wired in, the engine started and ran on both cylinders. It just goes to show that new is not always best, especially if the parts are after market parts.  Sometimes the old well worn parts will do just as well. We had previously given up trying to get the carb rubbers between the carburettors and the air filter box to fit the carbs, because they were had shrunk to much and were to hard.  A pair of, dare I say it, aftermarket filters had been sourced and fitted.  Once the engine had warned up it became apparent that some work with the jetting and needle positions is going to be required to get the engine responding correctly. It is a shame that the original air filter box couldn't be used, not only for the look of the bike but because engine designers generally have a very good idea how to construct air filter boxes to get the best out of their engines. The engine itself ran really quietly which is testament to its relatively low mileage. There was a whole variety of other work still to be done including fitting the speedo/tacho, fitting the headlight, fitting the ignition switch, fitting the clutch lever assembly, fitting the front mudguard, fitting the rear inner mudguard, bleeding the front brake, connecting up the wiring for the brake lights and indicators, sorting out the connecting link on the new rear chain, fitting a chain guard, re-fitting the sprocket cover and finally fitting the seat/tank/tail hump.  One piece of good news was that the rectifier/regulator was doing its job with the voltage rising over 13 volts as the engine revs were kept high.  Finding that the generator was doing its job was a relief. 





Ducati 250cc Single cylinder racer circa 1972.  


In the main it was Jon and Kieran that worked on the bike.  Work was done to repair a damaged thread on the top mounting of the left hand read shockabsorber and also to install a new rear sprocket. Once working again this will be a truely remarkable piece of motorcycling history.  I know from listening to Jon and Kieran that for best carburetion the carburetor will need to be mounted some 14 inches from the intake valve, putting it somewhere inboard of the rider's right leg.  That will be quite a challenge. 




Dniepr 650.

Annabelle continued her efforts to get the bike running properly.  After a lot of effort trying to get the bike running with a set of modern carburetors and some after market air filters, Annabelle refitted the original style carburetors and the air hoses connecting them to the standard air filter.  Whilst this didn't make the bike run perfectly, it ran a great deal better than it had done with the modern carbs. and after market filters.  Unfortunately a defect fuel tap prevented further efforts to correct the carburetor adjustment.  The thread of the fuel filter bowl decided to fail meaning a replacement is required before further adjustments can be made.





KZ550 LTD.

Kieran kindly assisted by enlarging the holes on the KZ1000 front mudguard we had managed to source from a UK breakers.  Although the front wheels of the two bikes were both 19 inch and the same width and the bolt holese were the same distance apart. Although mudguards were in theory covering identical tyres the KZ1000 mudguard was too close to the tyre until the bolt holes were alongated. Most of the work that was left to do (Apart from Carb balancing) was the work required to give it its overall final look.  The fuel tank required painting, and various minor ancilliary bits needed to be attached.  The secondhand replacement seat also needed to be recovered.