Recycled builds- old motored builds given another life 80cc build

Have you ever gone on a trip and sneakily purchased some things from facebook marketplace or whatever digital fleamarket you have access to?

I had 2 hours in my local capital city and a plenty of diesel, i spammed whoever had listings for petrol bicycle listings within 40km.

I made 2 purchases and ended up with 3 frames, two engimes and some spares. The guy still has 3 more crates of engines and parts and i havent been back in months. I will likely hit him up soon and get the rest... maybe. I am more likely to get a newer build and tune from the bench first and put it in a nice frame from day one.

Currently my dream build is a state cycle co klunker, a bt110 hand filed and somewhat sorted with a nice pipe and some motorcycle controls, bobber seat and short mudguards. Probably lights too.

But that isnt this build. This Japanese Shogun frame had a 80cc kit fitted and was sort of sorted, and then thrashed, and trashed and abandoned.

I stripped it, modified to a single speed and fitted a new set of forks. These yellow forks where supposed to be 1" steerer forks for my Gemini build, but alas- they are 11/8"...

I have some pre- built wheels of sketchy provenance, but it works. I run them after i straighten them, and if they falter; thats when they retire.

I have a stock of bikes and have grabbed a lovely welded stem from an old dirtjumper that i had repurposed as a street crawler, and i have some 22mm low cruiser bars inverted for that drop down riding position. I will likely get another bent seat post and put a sprung saddle on it for comfort. I dont know why, but i am still going for the BT look. I will get over it soon.

I start by building the bike first with my builds as i like to be able to stop once i have the power unit in it. I also find most of my problems with my builds are with the base bike not so much the motor kit of late. I am a small engine mechanic by trade and rarely suffer with the mechanical failure of the power unit... the carbies though... and the bike- every time. I spend most amount of money on tyres and suspension in any vehicle.

I have a reed kit, slotted piston, power pipe (red banana 🌶) and a dremel. Ha ha ha. I have some time to port the head and match the ports.

I have a selection of carbies and will probably go with the roundslide style.

It would be nice to have mudgaurds, lights and i will likely just start the build with kit parts, and maybe get some pitbike parts to help give it a bit of bling.

It will be nice to have cantilever brakes on this build. A first for me. It's always been those classic brakes on all my other builds. (Wait- is this my 5th? 6th?)

Oh, did i mention i am rescuing the engine from one of the old fellas bikes too?

The engine had rust on the crank and i have to clean the crap off it and re-assemble it. I tried to find bolts locally an ordered from the local old guy who has a large supply of h.t. bolts, but he didnt give me allen bolts, which is what inasked for- he got me hex bolts. Bum. So i have to go and get a new set of bolts.

Also, the frame has a 45mm downtube and the cdhpower 1.5" adapter is not perfect. So i will be building my own adapter plate with a tractor exhaust U-bolt and an alloy plate.


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I bet that frame is light and nimble.
Soooper light. Alloy bars, stem... who knows, might snag a solid alloy seat post. Not sure about an alloy tank, thats asking a bit of price.

Working on the mounts at the moment, i have some 16mm t6 alloy plate and some 42mm exhaust clamps. Need to get some 85mm long u bolts and some other hardware (threadlock bars, nyloc nuts, washers, 8mm tap, etc, etc...)
Aaah geeez. I just finished making the bike part of the build, geting it single speed set up, new chain, brake cables and outers, found a huge bum seat, and chucked some nice levers on the flimsy alloy bars (they are going, sooo soft, i could feel the flex as i climbed on the bike) and then grips, and some fettling. I pedalled a few times and it feels ok. Apart from the bars.

Aaaand then, i fprgot to take a photo of the lairy single speed MTB...
Well, they are terrible photos with busy backgrounds. But with the limited time i have to put the engine together at least i finally remembered to take a photo this time.

Currently working on all of the porting and the transfers. Matching the gutting of the ports i am doing with the die grinder and then matching those case to case, so the transition of gases and compressed combustion mix is not impeded by lips, burrs, lumps or other obstructions.

The next trick will be to thoroughly clean the bejesus out of the bits before reassembly.

Stay tuned kids!

I did one side of the barrel to the crankcase last night, who knows- i might have time tonight...

I did find a solid alloy seatpost, it's not the style i like, but it will do.


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