A while ago I bought this little book about how to build your own 'motor bicycle'. It was printed in 1906 and was aimed at motorcyclists who understood engineering principals, methods of metal working and had a bit of talent. Now, I believe I understand most engineering principals, have a good grasp of metal working and have a pinch of talent. To this end, I have decided my next project will be to build my own bike, an MEC (Murdo Engineering Construction). With all my travels around old farms I have dreamed of finding an old Aussie made bike rusting behind a shed that I could bring back to life. So far the 1937 Royal Enfield has been the closest I have got. Australia has had over 400 bike makers since the end of the 1800's. The major centres of Melbourne and Adelaide being the most prolific producers (still, see Drysdale, Hallam,etc), with smaller firms supplying forks, tanks, wheels,etc. Most of these bikes have been made with imported and locally made components, although some have been wholly made here. Our isolation from Europe has helped to foster a 'home made' attitude in Australia, and this is what I am going to do. This is the book. It has dimentional drawings and tells of how to cast your own frame lugs and what sizes of tubing to use. I transfered this to a piece of board I mounted on my drawing board stand.
First I started with the front wheel. I have two Suzuki TS185 wheels (one from tip, one bought from mate) I planned to use. The Tip one I disassembled and cut the brake drum from the hub. I turned the remains of the hub in the lathe so I could fit a piece of 50mm heavy wall alloy tubing over it and made a spoke flange plate to weld to it. Drilled the spoke flange and welded to the hub. Trimmed off in the lathe and looking good. Now that the front hub has equal size spoke flanges, I needed to make some longer spokes.
I always like to keep bits as they may be handy one day. This day I used the 36 spokes from the rear wheel of my Kawasaki F7 restoration. I cut and joined them together to make the 18 longer ones needed for the wheel. I TIG welded them together in my drill welding jig and while still red hot hammered the welds to compress the grain of the metal to make them stronger. A light clean up on the sander and ready to fit.
With the wheel spoked and trued it was time for some etch primer. I was given a Kawasaki KL250 bent frame (something to do with a tree?) that I cut the head stem from as this would save me a lot of work making one. The plan calls for 1 1/8th" tubing (29mm) which is no longer available, and I had two lengths of 1 1/4" (32mm) left from when I built my front engine dragster years ago so decided to use that. When the metal shop opened again I was able to get more bits I needed and put in a couple of hot days in the shed. I cut the stem from the bent frame and cleaned with grinder. I made some dummy sleeves as the original frames were furnace braized and I use the sleeves for looks. The tubing is welded to the stem, then slip the sleeve up close and do a wide weld so I can grind it off smooth. Any remaining bits I get with a rotary file in drill. This will look just like a casting after it is sandblasted and painted. Not bad for a days work.
With some time spent on the lathe I made a front engine mount and modified the steering stem to take the spindle for the girder forks. The rear engine mount is a simple bent piece, also mounted the rear forks. Looking like the picture so far.
OMG he is at it again. Much as I try to have a laugh you could not make this stuff up. This is priceless Murdo. Love it.
You would be welcome Pat. Of course I'm making it Maelstrom, and it is ok to laugh. Thanks canafforda600.
2016, we are but a dozen days into the new year and already "The good Doctor" has plans afoot for his latest project. He has taken a book 1st printed over a century ago and is about to create his own motorcycle, this is an event not to be missed! So begins MEC, we are in for most interesting journey......watch this space!! Thanks Murdo, like many others I hope one day to visit Tamworth and see first hand where so many projects have been created.
Today I made the girder forks. This involved cutting the tubing to length, fitting between branches of my Jacaranda tree and bending to match the drawing. I cut some templates from cardboard for the ends, and when happy with the fit transfered to 6mm plate and plasma cut them out. I bolted the ends together to ensure correct alignment before welding. Then welded the sleeves over the top. With some grinding and finishing of the welds and reaming of the mounts it all went together. Will be off to buy some bolts, nuts, etc, tomorrow so I can do a trial fit. Painted the wheels today so when they are dry will get the new tubes and tyres on and be able to finish the rear wheel mounts. Progress will slow a bit now as I have many small bits to turn on the lathe, and will be waiting for ordered parts.
Seems a couple of posts have been deleted. To reply, I was thinking of buying a barrel, piston, rod, valve assembly from the Chinese Chang Jiang (BMW R71 copy, about $150 delivered) which is a side valve engine and making a crankcase to fit it using the patterns in the book, but I don't think my lathe is accurate enough to make cranks and the cost of paying an engineering firm to do it would be too much. The two stroke 250cc Sachs engine I did a trade on will be a lot less work than the modifications to the four stroke I was planning to use, so will go with that if it is in useable condition. Got the forks finished and mounted loosely. Have been trying to find suitable mudguards with no success, so may have to make some rollers and make my own.