This is my MZ TS 150 trail bike. It started off many years ago the same as the shed, previously pictured on here, a standard road going bike. When I got it the machine had been half converted into a trail bike. The previous owner had no further need for it and I am a sucker for a poorly motorcycle so I bought it. It's return to proper working order has been a labour of love for sure and is ongoing. It is no exaggeration to say that almost everything on the bike was either broken, worn out, bodged or a combination of all three. It got to my house under its own power, but frankly I was surprised it managed that short journey and if it was a horse, it would surely have been glue many years ago. Since that time various parts of the bike have been painted, a 21" front wheel and high level mudguard fitted and dozens of small repairs carried out before putting the bike through its MOT test and getting it back on the road.I was skint at this time and so needed to fix or replace the totally worn out engine upon the cheap. I managed to buy a complete engine bottom end for a tenner with the side covers missing and worn out primary drive. The piston and barrel from the original engine were usable and I had enough bits to make up another primary drive and fit the engine covers in my spares collection. I had to buy a few circlips and gaskets and the total cost for an engine that ran pretty well was £13. Result. However it was all a bit too good to last and the the engine which had obviously been stood for years before I got to it started to pump gearbox oil out the breather hole in the crankcase after a few hundred miles. As this is an early 150 engine with the main bearings lubricated by the gearbox oil the main bearing seals are inboard of the main bearings and therefore it is necessary to totally strip the engine to change them. These seals have gone hard and are now leaking allowing the pressure in the crankcase to transfer to the gearbox and pump the oil out.
No longer skint, I paid to have another engine to be rebuilt and I got the bike up on the bench and resting on axle stands supporting the footrests (there is no centre stand on this bike) to swap the engine over. At the same time my electrical guru friend Nigel is to fit one of the electronic ignition kits to the bike to get rid of the 6 volt electrics and reduce the bike's maintenance requirements. I also have removed the swinging arm and painted it as it was getting a bit rusty.
I was surprised and rather fed up when the replacement engine was dropped into the frame to discover that the rear engine mountings were rather a slack fit (see photo below)
It turns out that the later 150 TS series engines have a narrower crankcase casting at the rear, hence the large gap which needed to be filled. I had no idea that this was the case and that there was a difference between the engines but if nothing else it shows that after over 20 years of MZ ownership I still have plenty to learn.
It turns out I needed 4 of these beasties, 2 of which are shown here. That sorted it, a spacer each side, top and bottom rear engine mounts.The next problem was I discovered that the back sprocket cover and speedometer drive gear which is enclosed inside the cover were for a 250 with a 16" rear wheel instead of the 18" wheel fitted to the 150 TS bikes. This explained why the speedometer was 10% out. I have managed to get a replacement drive gear (the two are different and therefore not interchangeable) but I do not have a sprocket cover and I have recently found out that they are made from that rare material unobtanium. I am not used to this with MZs, most parts are available off the shelf and there is a good chance that more will be made available as pattern parts at some stage in the future, but in the mean time I will have to find a second had one which is proving a little difficult. No doubt there is one somewhere.
I am very aware that there has been a lot on here about spannering and very little in the way of rides out in recent weeks. I did have a good ride out a week or two back getting more RBR clues but other than the clues themselves I did not take any more photos. I intend to remedy this soon, watch this space!
Interesting about small design changes, eg engine mounts. I'm trying to make sense of my TS150 main crank bearings, which need replacement. The engine's an amalgam of a 1982 150 and a 1980 125 and has run fine for some years. The book shows the left hand pair of ball bearings wide open to the primary drive casing, meaning I suppose that they get thoroughly splash lubricated. But my engine seems to have a housing with a circlip, an alloy housing and what looks like an oil seal closing off that open space. Is this a mod on later models? There's a bore from the bearing housing into the gearbox, presumably an alternative lubrication route, but it's hard to believe that much circulation takes place to remove heat . Right side similar (well obviously the dynamo has to be kept oil-free). The right side ball bearing in particular has clearly 'burned out' due to lack of oil, it's black and blue. My question: would it be wise to remove the outer left side oil seal altogether, to let more oil into those two bearings? That would certainly appear to be the norm on some engines.
ReplyDeleteLastly, I'm really a car mechanic, so maybe my bike tip isn't original after all, but here goes. Washing the rear chain in paraffin is messy. So find a 2-litre screw top plastic drinks bottle. Drop chain in, followed by 250ml paraffin. Replace cap, shake vigorously for a minute, then drain. Repeat with fresh paraffin as often as necessary; it works as well as your washing machine (except you shouldn't put bike parts in with the laundry!).
Next, drain bottle and replace with chain saw oil, shake and allow to soak. Finally, cut the top of the bottle off to get the chain out (it's nearly impossible otherwise), hang up and allow surplus oil to drip off overnight. Job done and your hands are still clean!
I'm sure purists won't approve of chain saw oil, but my bike thrives on it. After all, it's deliberately formulated not to 'fling' (it's 'thixotropic' - very tacky), you don't have to boil it to get it to penetrate the rollers, and it's difficult to believe that the chain on a low-ish powered motorbike needs to endure anything like the severe on-off loads and filthy environment of a chainsaw......DUNCAN H.