Workshop Session on Saturday October 19th 2024
Workshop blog update for Saturday October 19th.
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| The assembled throng busy in the workshop. |
First and foremost we welcomed Andy Jenkins AKA ‘AJ’ back for the first time since his horrific accident back in April, it was also great to see his wife Meryl with him. AJ looked surprisingly good considering his 6 month ordeal to regain his fitness.
Kawasaki KZ550 Limited.
It is fantastic to be able to say that AJ set to work on the bike with assistance from Jack. A number of wiring issues were tackled and at one point the bike could be found laying on its side on the workshop floor. Not because it had toppled over but because AJ and Jack were replacing the oil pressure switch. The oil pressure switch is located on the bottom of the engine and had the bike been left stood up, a large proportion of the engine oil would have drained out onto the floor. WIth the bike on its side oil loss was minimised.
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| Wrestling with a wild KZ550! |
Kawasaki Z250 Scorpion.
Steve worked to identify further parts that needed to be replaced to complete the rebuild. The front and rear brake master cylinders would appear to be two of the more problematic items. We don’t know if the front brake master cylinder works correctly and in any case it needs a new brake lever. Steve had done some internet searching and had found that what appeared to be front brake master cylinders for the Z250 were widely available through Ebay and the like. However, more detailed research showed that these were almost exclusively for a much younger bike also named the Z250 or BR250 which appeared to have been manufactured between 2010 and 2016. So, there is no certainty that they fit our 1979ish bike or if they do fit, whether they work properly. As for repair kits, Graham could only find one for sale from Zpower for the princely sum of £59.99. The front brake master cylinder needed a little more examination before money was spent on it.
The rear brake master cylinder seems to have stood disconnected from the rest of the system for some time. At first it seemed as though removing the piston from the cylinder was impossible due to the rust. However Graham got it spinning round in the bore using an Easy-Out (Normally for removing broken bolts) to jam into it and turn it. However rust built up around the neck of the cylinder meant it took Graham and latterly Keiran over an hour of fighting with the piston to encourage it out of the cylinder. Once it was out in the open a yellowy powder could be seen filling the spaces in it. This yellowy powder had once been the brake fluid!! More research on the internet revealed the fact that Z250A1 rear brake master cylinders are rarer than rocking horse poo. So rare in fact that Graham failed to find one. The only company claiming to supply new master cylinders was the Dutch Company CMS who were awaiting fresh stock and would charge 175 Euros plus postage to get it over here, if and when they got one. Decisions now needed to be made. The seal on the old cylinder looked in reasonable condition so it might be possible to clean the components up and rebuild it. Alternatively we could wait for the very expensive item from CMS or we could purchase a kind of universal cylinder for not much money and adapt the frame so that it fits. What would be decided? Find out in the next thrilling episode.
A further issue making this project more challenging was found when Steve located its sprocket cover. The sprocket cover should house the clutch actuating mechanism. In this case it is an arm that is rotated by the clutch cable, when the clutch lever is pulled towards the handlebars. This in turn moves the mechanism in towards the crankcase, pushing on the clutch push rod. As the clutch push rod is pushed through the gearbox main shaft, it begins to push on the clutch pressure plate. The reduced pressure on the clutch plates allows them to slip, breaking the drive to the rear wheel. Our problem was that the actuating mechanism was missing and couldn’t be found around the workshop. Graham subsequently searched around the interweb and managed to find a vendor in Sweden selling the actuating arm for the equivalent of £60.00 plus £12.00 postage. In addition, a plate containing three ball bearings that the arm pushes against was also missing. CMS in Holland offered these for sale so by the time all the missing parts could be replaced it would cost the club around £100.00.
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| On the verge of success wth the master cylinder piston almost out. |
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| Rear brake master Cylinder piston finally removed. |
Jialing Trials bike projects
Don, Andy and Guy worked on getting the finish on some of its components back up to an acceptable standard. Don spent time polishing the rear shocks and spraying the suspension springs black once he had cleverly masked off the chrome shock absorber bodies with paper to keep the black spray paint off them. Andy and Guy were last seen painstakingly preparing the engine for a coat or two of heat resistant silver paint which would no doubt be applied at the following workshop session.
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| Preparing the engine for painting. |
Dnepr 650.
At the previous session Annabelle had removed the cylinder barrels to find that both pistons had suffered a degree of seizure that had left score marks up and down them. As the engine was not running under load when it had come to a sudden stop two sessions previously, it was fair to assume that the new pistons installed by a previous owner had not been properly matched to the cylinders. This meant that there was probably not enough clearance between the piston skirt and the cylinder causing the aforesaid seizure. During the current session Annabelle installed some replacement cylinders and pistons that will hopefully see the seizure become a thing of the past. Replacement cylinder heads were also going to be installed that would hopefully overcome the issue causing misfires especially on the right hand cylinder. Again, it is a case of watch out for the next episode to see if this would cure all the bike’s ailments.
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| A well earned rest. |
Ducati 250cc racer.
Kieran assisted Jon with his personal project by fabricating a very neat bracket on which to mount the rear brake lever. It was a very well made adaptation and will play an important role once the bike is capable of moving under its own steam once more.
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| Braking new ground. |
Mal continued working to improve the appearance of various components but progress was hampered a little by the absence of brushing black paint to improve the look of some of its components. Mal had bought some but unfortunately had left it at home so painting those components would have to wait to the next session in two week’s time. This in turn would mean it would most likely be a month before work could begin to put the front end of the bike back together. That’s if we could remember how to do it by then!
TX 500 - No further progress made on this project at this meeting
In other news…
An article on the good work done by the club had been published in the November issue of Classic Motorcycle Mechanics with a two page spread on pages 26 and 27.
Graham and Andy put up the Spray painting tent on the stage area of the hall. It was as sizeable as expected, being roughly 10 feet long but was easy to put up. Even without the extractor fan installed in the window the previous week, the smell from small paint spraying jobs was contained in the tent. Once the extractor fan could be connected to the tent with ducting, even large spray painting jobs could be done without causing annoyance to others.
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| Let us spray! |
Kieran got everyone to take time out from the work they were doing in order to tell them about a simple feedback form he had designed. It was for attendees at our sessions to use in order to give feedback on how attending the session had impacted on their feelings. It also allowed members to share any ideas they may have on how to improve the club’s running etc. Kieran had constructed a technologically advanced cardboard suggestion box for the slips to be left in. The forms used a system of Smiley face type emoticons for members to illustrate their feelings at the start and finish of the session.