Workshop Session - Saturday March 9th 2024

We had a good turn out for our Saturday March 9th workshop session including 6 new members visiting the workshop for the first time. During the session of a variety of work was done.

DNIEPER 650...

A considerable amount of thought power was poured in Annabelle's Dneiper which was steadfastly refusing to run. Annabelle, Guy and Phil had tried various things to get the beast to come to life including replacing the bike’s carburettors but it refused to respond. Instead it gave us tantalising signs of life without starting with the occasional pops and splutters. It even fired for a few revolutions. The bike has a manual advance and retard mechanism. This means that the rider controls the amount in advance of top dead centre that the spark plug is fired at. To cut a long story short, the spark needs to occur further in advance of top dead centre at higher engine speeds than it does at low engine speeds. As engine design advanced the function of altering the ignition timing was taken over by automatic advance and retard units. These consist of a pair of weights which fly outwards against the tension of springs under the effects of centrifugal force. The faster the engine is going, the more the weights fly out. The more the weights fly out the more the points cam turns in relation to the shaft that is turning it.

Ah well, a little more head scratching would be required before the Dnieper would be a runner.

Ah well we've tried this this this and this, what about trying this?

The Piaggio Velofax...

Graham and Jack did a little work on this little red Italian large wheeled moped. The engine felt very insecure in the frame. This was overcome when it was realised that the mount that the engine pivots on was not part of the frame and hadn’t been bolted up. Missing components still frustrate the process of getting the bike running. In this case the ignition lock and the workshop manual have disappeared but hopefully not forever. Turning the engine over with or without a battery produced a few very strong sparks at the spark plug but they came, went, came again then disappeared. Installing a 12 volt battery didn’t change the situation. Would the manual be located? Would the ignition lock reappear? Would the spark ignite!!

Jiailing 125 trials bike project

Don spent time helping to perfect the filled surface of the fuel tank ready for painting. Andy made a fantastic job of spray painting the bike’s frame in ‘Post Office Red.’ A tricky job with so many different surfaces to try and cover, but as you can see from the photo it’s looking really good. It will be a shame to get it dirty one day. Hopefully the next session would be time for the bike to be put back together.

Honda Bros 400 Rebuilding Forks

Unfortunately the seals on forks Andy was working on at the previous session did not hold up to road use, with oil leaking from the seals, so this session he undertook a full rebuild.

With the help of Keiran, Andy stripped the forks down. Because the dust seals were new 2 weeks ago and he didn’t want to damage them when removing them, they tried to knock them out along with the dust oil seal, however Andy forgot that there was a snap ring between the dust seal and the oil seal which needed to be removed - no damage done. Once the dust seal and snap ring were removed, sliding the fork tube outwards “with feeling” popped the seal and the bushing out easily. All the parts were cleaned. We didn’t have any new copper washers for the socket bolt bolt at the bottom, so Phil H demonstrated how to anneal the copper washers.

The old bushes looked in perfect condition but they were replaced anyway, along with the oil seals and dust seal.

For reassembly, Don provided some red rubber grease to coat the seals inside and out. Phil showed how to reassemble the left fork and left the right fork to Andy and Keiran. With the three of us, we had some difficulty inserting the slider bushing between the slider busing recess and the fork tube - we did this very carefully with about 3 screwdrivers, but got it installed properly in the end.

For the right fork, Andy and Keiran put their thinking caps on. They figured out that with 3 small cable ties, they could compress the slider bushing around the fork tube so it would more easily slide into the slider bushing recess. Using a fork seal hammer against the back-up ring, they very gently and easily tapped the slider bushing halfway into place. They then used a pick to extract the cable ties from under the back-up ring and then tapped the slider bushing home.

Fresh fork oil was then measured into the forks and air gap checked the caps put on the top, reminding Andy to torque up the caps once the forks were clamped in the yolks on the bike.

On the left of the bushing you can see pitting where chunks of the chrome are missing. If your fork seals slide over this it, your bike will fail the MOT because it will quickly damage your fork seals.

Honda Virgo 650

Mal had bought his Honda 650 Virgo in for assessment. It had stood unloved for 8 years. Despite this, there appeared to hope for the 2002 (Crikey that’s 22 years old give or take!) bike. The engine oil appeared to be very new and the engine turned over with the aid of a spare battery and jump leads. The final drive chain and sprockets although rusty, appeared serviceable. The rear sprocket has plenty of life in it. The chain is an O-ring chain, so hopefully the grease had been retained inside it and a good coating of suitable chain lube would extend its working life. A variety of jobs were identified as needing doing. These included…

Obtain and fit a new battery.
Lubricate the final drive chain with O-ring suitable chain lube.
Front and rear brake callipers needed overhauling as both were partially seized.
Replace front and rear brake pads as a precautionary measure.
Steering stem bearings needed replacement as they were notchy at the dead ahead position.
Carburettor overhaul. Although the tank had been drained when the bike was laid up it seemed that fuel had been left in the carb and from its horrid smell it had gone off and had very likely blocked some of the jets. On inspection through the fuel filler, the inside of the fuel tank appeared to be rust free.
Front and rear tyres were beginning to perish and for safety sake would have to be replaced.
The ignition lock only just about made contact and would need to be disassembled to get a good solid contact.
The tail light didn’t work - A minor trifle.
Strip and overhaul the rear suspension arms. More for safety sake than anything else, in case any of the bearings had seized. Although some parts of the shockabsober were heavily corroded, the chrome of the damper rod appeared to be in good condition and there was no sign of oil leakage on it. It will have to be checked again after the bike has been out for a good ride (Hopefully it will get that far!)

Finally, a huge thankyou to Steve Whistance for managing to change three tyres during the session. We wondered if there was a tyre changing record up to be broken.