Work on the engine

I finally received the gaskets and assembled the pieces yesterday.

I'm applying a thin layer of 350°c rated red silicone for a perfect sealing.

New head cylinder gaskets

Air filter, cutted to the right dimensions and soaked with 2stroke oil to glue particles.

Admission pipe set in place

Piston and cylinder 

Gasket with thin layer of silicone

Very clean parts, assembled with a torque wrench

Mounted back on the moped

Exhaust gasket with silicone on the both sides

Perfect sealing. I do this cause I had leaks in the past.

The moped ! I oiled the chain, cleaned the rims/body and changed the gasoline filter, now I let the silicone dry overnight, I will try to use it tomorrow. The engine compression is really good.

I ordered parts on internet to fix the engine (new carb jet, gaskets), fortunately I had another piston and cylinder, but I had to clean it. As the moped was temporary not functioning, I took advantage to clean it deeply.

The carb, cleaned with gasoline

I used the same brass jet from a propane blowtorch to fill the choke hole. I just soldered on the small hole with tin solder.

The piston, in very good shape once the carbon removed (soaked in gasoline for 2 days, it came apart easily).

Fresh piston rings.

I also had to adjust the gap of the piston ring. 0.2mm is perfect.

Using a needle file to slowly approach the desired gap.

Test with a thickness gauge, 0.1 should pass easy, 0.2 should pass with a little bit of resistance, and 0.3 shouldn't pass.

The two rings with the same gap.

The rings are set in place.

Rear sprocket cleaned!

I flushed the crankcase several times with gasoline to remove all the brass dust, I moved the connecting rod in case particles were trapped inside the bearings

I checked with a small flashlight, perfect. (the green liquid is 2 stroke oil) I used rubber bands to

secure the connecting to avoid shocks to the aluminium case.

The engine is now waiting for his reassembly, I should receive the gaskets in a couple of days.

See ya and sorry for my English, pretty sure I made a lot of mistakes ;)

How I fucked the engine myself

Hello there. The engine worked flawlessly for months, until a brass screw I used to fill the choke cable hole on the carb (the choke is useless for me) got sucked into the cylinder. The "screw" is an injector from a propane blowtorch, there was a brass filter inside, responsible for the engine destruction.

Some pictures :

At first I thought the compression loss was from a leak of the cylinder head gasket. I changed it with no difference.

Then I took a look at the cylinder and piston...

Totally fucked up. the bottom piston ring is even set!

The crushed brass filter I found inside the crankcase

which was originally inside the screw..

The cylinder/piston is no more usable, here's a new cylinder! Not brand new but in pretty good shape.

I have cleaned the crankcase with gasoline and turned the crank to help metallic particles to fall off.

Some news of the Peugeot 103

Three years after launching this blog, I've forgot it a little bit. Time to give you some news of the moped ! I have made the decision to turn this blog to English, cause there's also moped overseas ;)

During the 3 last years, here's the list of the modifications :


I've removed the pedals/bicycle chain and added an aluminium pulley instead of the stock plastic one.

I changed the chain for a more beefy one (KMC size 420). (I took the picture today after cleaning it with gasoline)

I changed the throttles/handles and cables.

The shocks absorbers were dead, I changed them.

Changed the crankshaft and bearings

I tried to switch the light into LEDs (10w front/2w rear, can work but unfortunately the capacitors of the drivers blown up cause the voltage was too high. That was a simple setup with a diode bridge rectifier and 12v led drivers)

I have currently no light on the moped and I should fix it soon!

I also changed the exhaust pipe for a Polini custom from the 80's that I bought on leconcoin (Craig's list lookalike website) but unfortunately the exhaust cracked, I've soldered it, hope it will last this time. It's stored in a box, the moped currently have a stock exhaust.

The stock exhaust I currently use

Polini custom before cleaning

After cleaning !

The carbon chips I removed with blowtorch and mallet

I forged a custom mount

And then, after weeks using it the crack happened

I've removed the decompression valve and replaced it with a switch which turn off the ignition system. So no need to have a cylinder head with decompression valve, I bough a Malossi one without decompression valve.

The switch, located inside the toolbox

Some pictures of the moped and spare parts I changed years ago

After cleaning the moped body

Cleaned rims with fresh new tires and brakes

Brand new carburetor

Oil filter I use (cheap on eBay and have a magnet to collect the metallic dust inside)

 While I was cleaning the inside of the tank. It was quite rusty, treated with phosphoric acid.

Cleaning of the fork with gasoline, lubrified with 2 stroke oil. Not ideal but it works.

 And other stuff 

 B8HS NGK spark plug I use.

I tried a Doppler exhaust, oversize and ridiculous, too low. Not for me.

At the beach !

That's all, stay tuned :)