Motorized bicycle engine top end rebuild and an engine stand

1. another tool to make life a little easier and to protect the piston form being broke and when you put the cylinder back on this is very handy. Would this be a pain to try and describe by words alone. just a piece of wood with a slot for the rod and it steadies the piston like a third hand

2. clean up gasket areas and wash cylinder and head with warm water and dishsoap to degrease it

3. There is no machining on the cylinders top and its a good spot for a head to start leaking from in the next pic I'm lapping the cylinder to clean it up for a better seal at least it makes me feel better. I also did the seal ring on the head no need to get carried away as soon as the rasied ring turns a little dull form the sanding stop and clean it.

4. using 320 wet/dry sand paper glued to glass and soapy water to keep sandpaper from clogging just smooth it up

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1. after all lapping grinding etc. clean with warm soap and water.

2. this is one way to make a pattern for a gasket I'm using the studs to hold the paper in place which is computer paper and then I rub my grubby fingers on the paper transfering the grunge on to the paper.

3. explains itself


4.as you can see this is one way to make a pattern and not use a ball peen hammer and risk damaging something

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1 & 2. knocking out the base gasket cutting the excess with my punch then on to the scissors


3. some info on what I found on this engine


4. I only smoothed out this area and another out of focus pic. pointing to the transfer ports shoulder.

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1. got the studs in and the base gasket in place and the little wooden helper inplace I also cleaned the crankcase in the solvent tank blew it out with compressed air and shot some oil on all the bearing surfaces no pic. on that as you can do it with out pic.


2. oiled piston and cylinder indexed the rings so I won't break a ring and the cylinder almost falls in place.


3. I spray a very light coat of cheap aluminum spray paint on the head gasket before I install it. No I didn't paint it there I did it out side.

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torque pattern that I used and I forgot to show me putting on the head.


A little dab of grease on the gears for good luck

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1. Grease the other side it will help hold the ball and short rod in place. I don't know if you noticed or not but I don't like to work on shlty things I have to at work but not here I've been so greasy and oily I could wring out my underwear form rolling in oil and grease while doing an industrial engine/compressor, so I take the time to clean stuff up.

2. something I forgot a light sanding on the engine mounts helps to smooth them out, knocks off any rough raised areas that will later wear down and cause your engine to jump ship. doing the front mount. emery cloth and frame tube of proper size well its kind of close to the right size. Some thing else remember to cover up all engine opening when sanding the mounts you don't want any metal dust inside of the engine. The sanding tube is a bike frame tube the same size as what the engine is going to be mounted on the bike. glue the sand paper on to the tube and sand, check the fit of the engine on the frame so you can get the engine to fit nice and snug to the frame tubes.

3. rear mount getting it as well and I hate sanding ask me about building a composite airplane what a sanding contest that was 2years of it and I quit and stuck my homemade engine on it and been flying it since 1985 and still works and hasn't killed me YET got some skid marks in the shorts tho from some of my festivity's


4. the end hope this helps and doesn't confuse you more if it does don't work on an engine take it to someone who can. Naw! Jump in there and get NASTY.
Norman

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