On the Bench 1

This slightly sorry looking machine is a 1970 MZ ETS 250 Trophy Sport. It's a pretty rare bike, only about 16,000 of them were ever produced, compared to hundreds of thousands of most of the other MZ models and of that total I believe only about 600 came to the UK. The bike has not been used for about 18 months now as the headset bearings failed and a fork seal started to leak. At the same time I decided to uprate the electrics. I wish I had thought of this blog a little sooner as I have recently changed the faulty bearings and seals and it is quite an involved and interesting task, but I am not taking it all apart again just to take photos!

The bike is well on the way to completion now, I am looking forward to riding it again.

This is a VAPE ignition kit system from Power-Dynamo.biz in Berlin. They are not cheap, but are well worth the purchase price if you can be fairly sure of keeping the bike for quite a time as they give 12 volt electrics which are a considerable improvement on the standard and now very old 6 volt system and sparks are provided by a maintenance free flywheel magneto, as pictured above.

I must at this point acknowledge the invaluable and very kind assistance offered to me by my good friend Nigel who is a wizard with electrics, whereas I am most certainly not. It is he who has installed the kit on the bike for me and hopefully tomorrow night we will get the bike in one piece and see if it will run. There is a strange electrical fault at the moment which I do not understand, but I suspect Nigel will sort it out quite quickly.

More news soon I hope!

Hydraulic Work Benches

I have lived in this house for 2 1/2 years now, before then I lived in a tiny terraced house in a quiet street. Bike maintenance and repairs tended to happen in the street, weather and light permitting. When I moved here, I got a big garage and went from working in the street to scrabbling on the floor in the garage. I regarded this as a huge leap forward, being able to work when I like and not having to pick up all the tools every time I stopped work.

Some time later I made another huge leap forward, I bought a hydraulic bike work bench from a friend of mine who was turning it out of his bike shop in Leeds. Money changed hands and now I can lift bikes up to working height. Fantastic, and once I had done this it was plain there was no going back to scrabbling on the floor. Since then I have augmented this bench with another, more a platform on wheels which lifts up underneath the middle of a bike leaving the wheels in mid air. My good friends from the MZ club, Joe and June got me this from a local trade place very cheaply. This is a very useful stand for bikes which have no centre stand when adjustments to the wheels of forks need to be made. I can't recommend a proper bike stand highly enough.

As the projects get bits of work done on them they tend to come on and off the bench to suit whatever I am doing. I will be writing about progress on whatever is being done on the bench under the heading On the Bench.

Jawa oil pump, partial success

Well, I went on a run up and down the Colne Valley in West Yorkshire this evening to see if I had cured the oil pump leak. The answer is no, but it does seem to be less then it was. I will have to keep an eye on it. Above is a view of the oil pump on the side of the engine. Originally the throttle cable would have been connected to the wheel on the right hand side

I had a good run though, most enjoyable. The weather was a bit showery but I got some good photos I think.

This is by the side of the road about 4 miles from where I live.

Here is the view over the wall. I feel very fortunate to live where I do.

Nice daffodils!

I wandered down the road to Merrydale, a tiny hamlet in the bottom of the valley. This is the view to one of the lovely cottages there.

The road turns into a rough track just over the old stone bridge over the river. There is no turning circle so I would never take a car down there!

And so the locals have put a sign up because they are fed up with folk going down there and getting stuck. In case you can't read it, the sign says "Sat Nav Wrong Use Brain" I am a big believer in maps and common sense, so i find this all very amusing.

Jawa oil pumps....

I am very fond of my Jawa model 634 350cc twin, it is identical to the bike I had when I was 18, but without the tradesman's box sidecar I had in those days (I always was a bit "anti-fashion"). Originally the bikes were fitted with a 2 stroke oil pump. These are something of a disaster as they always seem to pump too much oil into the engine and are so stiff to operate they usually break the throttle cable every few months. I remember on at least one occasion when I was a teenager I had to get home with a pair of mole grips clamped on to the broken cable end to operate the throttle. On my present machine, a previous owner has done the right thing and disconnected the pump, oil now being mixed in with the petrol at a ratio of approximately 30:1. However, the oil pump remained, still driven by the end of the crankshaft and just pumping oil round through a loop of plastic pipe back to the pump inlet.

Recently oil has been escaping from the oil pump housing, so on Friday evening after work I set to. I removed the oil pump and the gasket where it bolts on to the engine appeared to have failed. I don't have another but I decided I would stop the oil pump from driving altogether so it can never fail out on the road. The oil pump has a quill drive and I attempted to cut it with a hacksaw so that the oil pump could not turn with the crankshaft. Two blunt blades later I gave up, the metal is surprisingly good quality and has been well hardened. Instead I stripped the oil pump down to its constituent parts and removed the drive shaft altogether, fixing the pump body back on to the engine with gasket sealer.

Later today I intend to go out for a ride to see if this modification has been successful. I do now have a worry that the pump body will fill up with gear oil and leak. If this does happen, I have a spare pump which I can fit and be back to where I started so I cannot really lose out. What I really need is a replacement primary drive cover for the engine with no oil pump fitted, as used on earlier and some later models of this bike. I have yet to find one though.

More later, with pictures if I can work out how to post them!

Projects currently on the go

I spend a lot of time in my workshop tinkering and I seem to always be working on several bikes at once. At the moment I am working on the following:

1983 Jawa 350 twin, model 634. Riding restoration while I try and get rid of all the oil leaks!

1970 MZ ETS 250 Trophy Sport. At present having a replacement electrical system fitted which will give electronic ignition and 12 volt electrics instead of the original 6 volt dynamo system.

1976 MZ TS 150 trail bike. This is running but the engine I built out of scrap when I was skint is not well, so there is a newly rebuilt one to go in with another new electrical system

More updates sometime, probably with photos once I have worked out how to post them....