Project Monkey Bike

I picked up a 55 plate written off 50cc clucthless monkey bike through my work for nothing that was an insurance write off. Took it to the workshop & wripped out all the lights, starter, electrics & speedo etc. Just left the kill switch wired in.

Picked up a few new chrome goodies for it today..... Gear selector, kick start, wheels, exhaust heat shield, front & rear mudguards plus a spare set of nobbly tyres.

Now ive got it running sweet & starting first kick, the next job is to strip it down, grind off the unwanted headlight brackets & relay tags etc, paint the frame up, spray the fuel tank, tidy up the wiring harness, fit all the bits `n` bobs & my lad will have himself a little toy for playing over the fields. Once im happy with his riding & control i will drop the 50cc lump out, fit a clutch lever/cable & bolt a 125cc lump in it.... Happy days!

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It will never win any concours events but it will look half decent when its finished & above all will be safe! Its got newish rear shocks already & brand new front fork internals plus new brake shoes.

Its got front & rear drums brakes with a 3 speed all up gearbox. When the 125cc lump goes in i will swap the front forks out too & fit a hydraulic disc brake up front.

 

The company i work for has about 100 road legal monkey bikes & believe me i have ridden them on the public highway & it aint a good experience! Lol
The 125cc monkeys are fun though i must admit. I was down at the workshop in Park Royal, London today & we were having wheelie contests on them..... Most enjoyable! Lol :upyeah:

 

No im a technician for a vehicle preparation company repairing monkey bikes & commercial valeting equipment plus doing our I.T installations.

They use the monkey bikes for the collection & delivery of vehicles in the rental business in the bigger/busy cities for Enterprise & Europcar etc. The frames or headstocks (depending on what make/model the monkey bikes are) have been modified so that they can be taken apart quickly, the seat, fuel tank & electrical harness are also quick release so the bikes can fit in the boot of the average sized car.
The guys then deliver the car & ride the bike back to base, or ride to the customers home/work address, break bike down, stow in boot & drive car back to base.

We have around 100+ of these monkey bikes & they do get trashed quite a bit!

 

It was on Top Gear a good few years back. We have been using the Monkeys for about 7 years now.

 

Will keep my ear to the ground for you mate, pretty rare that they get totally trashed & written off though.
The 50/90/125cc bikes all generally have interchangeable parts. You can drop any engine in any frame but the engine parts are not interchangeable across the 50/90/125 engine range.
The 50cc has upside forks, 90/125cc dont but they all fit the same frame/headstocks, rear shocks are the same length on all models but 90/125cc are stiffer & a bit chunkier, 90/125cc also has front disc hub instead of drum hub but the front & rear wheels/tyres are the same, so thats just a case of fitting a different hub,caliper/reservoir/hose & lever. The 50cc doesnt have a clutch but 90/125cc does but thats just a case of fitting lever & cable then connecting to clutch arm on gearbox. The 90/125cc has different size front & rear sprockets too.

So its relatively easy to keep all the bikes maintained & road legal.

 

Did some work on the Monkey bike this morning with the help of my son. I figure that if he helps me with it he will appreciate the work thats gone into it plus he will gain some mechanical knowledge & learn about how his bike works. Well, thats the plan :tongue:

Anyway, stripped it ragged within an hour

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Ground off all the brackets that we dont need that would normally hold, number plate/tail light assembly, rear rack, front & rear Indicators, headlight & horn plus removed the metal tags that hold the main body harness to the frame as they aint needed either. Then sanded off all the flaking paint & rust plus made good the welds where i had welded the frame back together after the accident. Also took out some more of the wiring loom thats not required

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Will de-grease it this afternoon & pressure wash it. Then paint the frame, forks & rear swing arm with the first coat of hammerite tomorrow. Got my lad cleaning the wheels & greasing up all the bearings for the headstock, swing arm & wheels.... Good lad! :upyeah:

 

Started giving the frame, swing arm & forks its first coat of paint this evening...

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Will take the wheels out tomorrow (which i might add my son did a lovely job of cleaning up & polishing today as they were thick with grime & chain wax/oil) & start the second coat of paint, then hang the bike upside down & paint in all the nooks & crannies.


De-greased the engine & gearbox, all cleaned up ready for a coat of engine paint in the week...

 

Yep! British Racing hammerite Green :upyeah: Probably going to do the fuel tank in it as well as i really cant be arsed to rub it down properly & spray it with the compressor as me lads only going to trash it & get it covered in mud :frown:

Might do the engine, gearbox & exhaust in black & the engine cases in silver. Then the lad wants "Monster" decals on it too :smile: