mztools@veteran.com.pl retro2oo.com An absolute novelty, something that has never been, no one produced the whole set of special tools for servicing MZ motorcycles, even in the days of the DDR these tools were available in their original form only for authorized workshops! Now you can have them!
Engine assembling device 22-50.014 Material: Bosch Rexroth aluminium profiles DesignLINE series, Stainless steel 1.4301 Machining: CNC turning, CNC milling Welding: TIG welding machine Additional treatment: Glass beads sandblasting Engine assembling device, basic and essential element of performing any repair. It allows you to rotate the engine and lock it in three assembly positions. Documentation of this tool is very poor so I had to spend a lot of time on it to design it. It is as I wanted both functional, robust and does not take up much space during transport. To make both engine fastenings I have used engine block and a FARO 3D Laser Scanner measuring arm, what allowed me to prepare simplified 3D model of EM250 engine and then use it to design fastenings with high precision. Detailed description of this process is shown below. The base was made of aluminum profile Bosch Rexroth, DesignLine series with dimensions of 40x40mm and fastening elements. Clever design allows after loosening 8 bolts to pack all device to the transport case so that it does not take up much space when not needed. Machining: Laser cutting, CNC bending Assembly device for gearbox 29-50.011 Very helpful instrument during (dis)assembly of the gearbox. With its help after assembly of the complete gearbox you can check its proper functioning before it is assembled in the engine.
Measuring instrument for end play of clutch driver (05-ML 13-4) 89-99.117 Machining: CNC turning, CNC milling Instrument necessary for the correct setting of the clutch driver end play using spacers of different thicknesses. It is very important to avoid problems with the operation of the clutch and the noise. On the other hand too small clearance may result in rupture of the clutch from shaft cone. The instrument comes with the measuring pin of a suitable length.
Clutch clamping device (05-MV 150-2) 89-99.071 Machining: CNC turning, CNC milling Welding: TIG welding machine Additional treatment: Glass beads sandblasting Device facilitates efficient (dis)assembly of the entire clutch. In addition, you can use it to check the correct operation of the clutch before mounting it in engine.
Holding-up device for gearbox sprocket wheel (like 05-MW 45-3) 31-50.404, Chain 428H Machining: Conventional milling Additional treatment: Glass beads sandblasting Device useful for loosening and tightening the chain sprocket nut with required torque. This is a newer version of this tool, available only in some newer service books.
Extractor for driving gear (05-MV 45-3) 89-99.064 Machining: CNC turning, CNC milling Welding: TIG welding machine Additional treatment: Glass beads sandblasting Very usefull tool for removing driving gear and also when removing chain sprocket. Pressing-out device for gudgeon pin (02-MW 40-3) 22-50.010 Machining: CNC turning, CNC milling, Laser cutting Welding: TIG welding machine Additional treatment: Glass beads sandblasting Tool necessary for the safe pressing out of the piston pin. Pressing element has been designed according to the original drawing so that the tool will fit both small and large MZ motorcycle engines.
Material: TECAST T (PA6G) Machining: Conventional milling Piston support 22-50.412 Device useful when removing and installing the piston, cylinder assembly and when blocking crackshaft while tightening the clutch with required torque. Used material ensures adequate rigidity and durability of the tool.
Machining: CNC turning, CNC milling Ignition timing gauge 29-50.801 Very helpful device for precise setting of ignition timing. This version is both much simpler and better than the original, due to the use of a dial gauge, which sets the ignition point with an accuracy of 0.01 mm. Device comes with the measuring pin of a suitable length. Anchor pulling screw (02-MW 39-4) 89-99.026 Machining: Conventional turning Welding: TIG welding machine Additional treatment: Glass beads sandblasting A useful tool when removing the alternator rotor. Right shaped end of the screw allows removal without damaging internal thread in the crankshaft.
Machining: CNC turning Drift for fitting sleeves (11-MW 3-4) 89-99.072 A tool for driving in fitting sleeve 7.26 to the proper depth in the engine halves. This sleeve is very important for proper centering of the engine halves during assembly.
Guide mandrel for gudgeon pin (05-MW 19-4) 89-99.051 Machining: CNC turning A useful tool to proper assembling the piston pin. It provides an appropriate inserting of the pin to the needle bearing. Drift for bearings 6203 and 6204 (11-MW 7-4) 89-99.073 Machining: CNC turning A useful tool when removing and necessary for the proper assembly of all gearbox bearings as well as the driving gear. Also useful when mounting sealing rings 35x47x7 in front suspension.
Drift for bearing 6306 (05-MW 91-4) 29-50.405 Machining: CNC turning Welding: TIG welding machine Additional treatment: Glass beads sandblasting Tool necessary for the proper assembly of the crankshaft bearings 6306, corresponding design provides simultaneous proper centering of the oil deflector plate. Tool is also useful during assembly of the front steering bearings.
Fitting tool for sealing ring 30x72x7 dynamo site 29-50.406 Machining: CNC turning Welding: TIG welding machine Additional treatment: Glass beads sandblasting Tool necessary for the proper installation of the sealing ring 25x72x7 on the alternator side. The mounting sleeve with polished surface ensures correct installation of the ring without damaging of sealing lip, while mallet ensures accurate seating of the ring in the engine casing.
Fitting tool for sealing ring 30x72x7 clutch site 29-50.409 Machining: CNC turning Welding: TIG welding machine Additional treatment: Glass beads sandblasting Tool necessary for the proper installation of the sealing ring 25x72x7 on the clutch side. Mallet fitted to the inner side of the sealing ring ensures accurate seating of the ring without damaging it.
Material: Steel S235JR and 40H Machining: CNC milling, Laser cutting Welding: TIG welding machine Additional treatment: Black galvanized Assembling bridge 22-50.430 The instrument is absolutely essential for repair of the engine. It has many applications, for (dis)assembly of the drive gear, separation of the engine halves, while pressing out the crankshaft and while removing gearbox bearing 6203. Welding precision of the laser-cutted base plate with CNC milled U shaped bar have been preserved through the use of welding template. The instrument was made exactly according to all dimensions on the original drawing. Set of screws in the appropriate length used to fixing of the brigde is included.
Ball bearing extractor (bearing 6306) 22-50.431 Machining: CNC milling Additional treatment: Glass beads sandblasting Tool necessary for the proper dismount of the bearing 6306 from the crankshaft. Construction of the tool provides dismantling without damaging both crankshaft and bearing.
Pulling sleeve (clutch-thread M 24x1,5) (05-MW 20-4) 22-50.435 Pressing spindle and pressing piece 22-50.437 Material: IMPAX Supreme 1.2738 Machining: CNC turning, CNC milling Additional treatment: White galvanized Indispensable tool when removing clutch from the crankshaft, when separating of the engine halves and when pressing out crankshaft. To made the tool there has been used high-quality material, supplied in hardened and tempered condition, characterized by a high resistance to abrasion, which provides high durability of the tool. Unfortunately, this steel is not resistant to corrosion so that the tool has been galvanized. For those interested, below you will find detailed description of steel IMPAX Supreme 1.2738 Extracting screw for bearing 6203 22-50.438 Clamping cartridge (like 05-MW 124-3) 22-50.439 Machining: CNC turning, CNC milling Welding: TIG welding machine Additional treatment: Glass beads sandblasting Device in conjunction with the assembling bridge allows trouble-free removal of the gearbox blind bearing 6203. Screw itself is also used together with the assembling bridge during the separation of the engine halves.
Heating mandrel for bearing 6203 and 6204 31-50.406 Heating mandrel for bearing 6304 and 6306 31-50.408 Machining: CNC turning Tools to be used to heat the inner ring of the crankshaft and gearbox bearings. This facilitates a correct and secure seating of cooperating elements. Diameter of the mandrels was properly sized taking into account thermal expansion of the material. The construction allows heating the inner rings of the two gearbox bearings simultaneously.
Spacer for crankshaft re-fitting (not in assortment from MZ) Machining: CNC turning, Laser cutting Welding: TIG welding machine Additional treatment: Glass beads sandblasting Necessary tool if you need to refit the crankshaft in the event of a bad seat in the bearing. Using this tool and the upper part of a clutch clamping device 05-MV 150-2 you can do it in a proper and safe manner.
Carburetor test housing (not in assortment from MZ) Material: Polymethylmethacrylate (PMMA) Machining: Laser cutting Glue: Loctite EA 3430 The instrument is necessary to determine the appropriate level of fuel in the carburetor float chamber. The materials used guarantee chemical resistance to petrol. Instrument is made in such a way that when placing the carburetor in it, you don t have to remove float chamber gasket, thereby risking its damage. The thickness of the gasket has been taken into account. The device is suitable for all BVF carburettors of small and large MZ motorcycles.
Spacer tube for clutch tightening (not in assortment from MZ) Machining: CNC turning Tool necessary for the proper clutch tightening with appropriate torque. Right dimensions provide sure tightening.
Aluminium thorn for gearbox / gearbox bearings (not in assortment from MZ) Material: Aluminium PA6 (2017) Machining: Conventional turning A useful tool when punching out gearbox shafts and assembly of certain gearbox bearings. The material used ensures that these elements will not be damaged. Impact bolt for fitting sleeves removing / Bolt for the rough adjustment of the clutch (not in assortment from MZ) Tube for the rough adjustment of the clutch (not in assortment from MZ) Machining: CNC turning Tools needed during the coarse adjustment of the clutch play. Mallet is also helpful when punching out the centering sleeve 7.26 of the engine halves.
Aluminium protective pads for vice (not in assortment from MZ) Material: Aluminium PA4 (6082) Elements that prevent damage to the surface of the gearbox and starter shafts during their fixing to a vice.
Summary: Thus presents a whole set of service tools for MZ motorcycles. It will fit engines EM250 of all models ETZ 250/251, and the newer engines EM251 used on motorcycles MZ ETZ 301 as well as all older models of MZ motorcycles with an engine capacity of 243 cm3. Most tools will also fit smaller MZ motorcycle engines with possible minor modifications.
Designing: All tools have been developed on the basis of 3D models and technical drawings which I have prepared. All significant fitments and tolerances of parts was preserved, everything exactly as in the original technical drawings of service tools. At the designing stage, as I wanted to avoid any mistakes I had a complete disassembled engine so that I could keep the control of all the important dimensions and, interestingly, it turned out that there were small but sometimes significant errors in the original documentation, they have been corrected. Tools, which drawings were not available or they were not in the range of special tools have been designed in large part thanks to the available service films where the dimensions were sized by measuring the engine components. In particular, making of the engine holder forced a precision measurement with FARO 3D Laser Scanner measuring arm, what allowed to create a simplified 3D model of EM250 engine and then use it to design with high precision both engine clamps. Below are only few selected measurements.
Selection of materials: Decision to make almost all of the tools of stainless steel is dictated by its high sustainability. I did not want to use cheaper steel, which would also force galvanization. Stainless steel 1.4301 is characterized by better parameters than materials proposed in the original documentation and have primarily one advantage - resistance to corrosion. The only downside it turned out to be much more expensive machining. Of course, also all of the screws, washers and nuts are made of stainless steel A2. Other materials used, as specified in the above description mainly provide durability of tools, proper selection of materials was not omitted. An example is the clutch puller, made of a material once unattainable and now available that guarantees parameters at a very high level. It is a steel by UDDEHOLM called IMPAX Supreme 1.2738, as interesting fact, this steel is 100% ultrasonic tested. Detailed specification of this steel IMPAX Supreme 1.2738 Machining processes: The contractor, who made all tools has a large machine park, mainly CNC, therefore making all elements with high precision was not a problem, of course, for the appropriate money. Turning, milling, bending, laser cutting, water jet cutting, welding, sandblasting, glass beads sandblasting, hardening, nitriding, galvanizing, chrome plating, are just some of the possibilities of this company. During the machining of parts, they based on 3D models and drawings with marked fitments, tolerances and surface asperities, so there was no possibility
for errors. In the era of CNC machines there wasn t also problem with obtaining tolerances at level of 0.05mm-0.1mm, even if the original documentation allowed greater tolerances. Welding: Machining of parts with high precision is one thing, but to reach the top of precision parts should be welded in such a way as to avoid mistakes. Especially for this I spent two weeks in order to design a special welding template. This provided that all elements will be properly welded. For welding there was used professional TIG welding machine and stainless steel wire, which, together with the combination of an experienced welder gave welds, which can be seen in the pictures of tools.
Additional treatment: After welding I had to remove discoloration caused by high temparature, I had a choice between etching or glass beads sandblasting, I chose the second option. So that tools that were welded were therefore entirely sandblasted which also gave them the nice surface structure. Some individual parts were also sandblasted to give them a surface structure which further improved grip of tools. Then, as the only two tools are not made of stainless steel they had to be protected against corrosion. I chose galvanizing. The bridge assembly is galvanized with black passivation, while the clutch puller with white passivation. Later on, the tools had to be marked, the choice was to make the descriptions using punches or laser printing. Due to unattractive look of punched numbers and expensive laser printing I chose yet another method, labeling using label printer. Labels have good adhesion to the material, durability and aesthetics. Package: For such tools can not do without the proper and nice transport case. I decided to use a dedicated carrying case from NEWBRAND company. The largest available model can contain all of the tools successfully and this is possible mainly due to the clever design of the
engine assembling device, which is located in the bottom layer. For the curious, I recommend to check the cost of the suitcase NB-45-10. Additional materials: To complete the set I decided to add additional materials. These include a poster with a list of all tools, a poster with EM 250 engine assembly diagram, poster with wiring diagram of MZ motorcycles after 1989 year (wiring diagram for motorcycles before 1989, lies in the service manual on the included CD), a poster with tightening torques list of all important connections
in the engine and chassis and a CD with the richest version of the service book and all available, original videos relating to the engine, electrical system and carburetor of MZ motorcycles. CD, one of a better quality - Verbatim CD-R DataLifePlus obviously is with dedicated imprint and specially prepared menu, but I leave this as a surprise:) I also know that these nice posters in the workshop conditions may have to be destroyed, do not worry, they are laminated. Payment and shipping: I do not know all the options of transport to your destination so the choice of shipper I leave to the buyer, you decide and choose the optimal option. We order a courier and then you make a payment using PayPal system. Courier receives the package, you get the waybill number and wait for your dream special tools:) For information purposes, the dimensions of transport case with additional cardboard packaging will be approximately 650mm x 450mm x 350mm and its weight about 32kg. Thank you very much for your time and I hope you appreciate the enormous amount of work towards creating something so far unattainable:) Successful bidding!!!