Poor mans method for timing Peugeot 103

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Many people starting out in mopeds lack a lot of the patience and special tools it takes to just get their new found hobby popping and smoking along the street after a confidence building "first engine start". The bike they have acquired may be partially disassembled reflecting the previous owners frustration. This repair tutorial will help you set the timing on your Peugeot 103 with the least tools possible.
But I need to say now that if your going to take up the 103 as a serious hobby then you absolutely positively must buy a flywheel puller. Most maintenance will require that you be able to remove the flywheel several times. The proper puller is the only way to insure that your not destroying your motor with the mechanics best friend, the HAMMER.

Here is the best puller for the stock flywheel and a link as to where to buy it. Puller


tools needed

Here are most of the tools we will need. you will also need a ruler or tape measure.

demo motor

I'm going to use this unmounted motor that just happened to be on the table for this demo.

pulling tool

Start out by pulling your flywheel. Most of you will already have your flywheel off which is why you are even reading this.


fly wheel off

feel piston

Using any long tool that will fit in the spark plug hole, reach in and feel for the top of the piston.

find TDC

With one hand on your feeler reach the other hand under the motor so you can turn the clutch bell. What we are trying to do is to move the piston into its very topmost position called TDC, (top dead center). It will take a little practice to get the feel for the spot where the crankshaft rocks over the center point and then starts to drag the piston back down. Just keep pressure on your feeler tool as you rock the crank back and forth and feel for the "no mans land" of the piston not coming up and not going down.
When you are comfortable that you have your crank rotated in the middle of the "no mans land" of TDC, you can let go of the clutch bell and remove your feeler tool from the spark plug hole.
It is at this point that you want to be very careful that you do not bump the clutch bell or to allow the crank to rotate

flywheel position mark created

Now you want to grab up your measuring stick or tape an measure 3/4 of an inch to the right of the middle of the plug wire grommet along the edge of the stator plate and make a nice visible mark with your sharpie. This distance will equate to 1.5mm of piston travel which is the stock setting and will put you on the dirt infield of the ball park you want to be in.

position flywheel

Next carefully align the timing mark on your flywheel with the sharpie mark you created and slide the flywheel onto the crank taper. Be careful not to let the crank rotate.

love taps

Give the flywheel some light love tapps to get the tapers seated.

tighten flywheel

After the love taps you should be able to move the flywheel carefully and begin to install the crank nut. I like to use a screw driver resting against one of the coil armature plates to anchor the flywheel via one of the window. Stay away from the points side if you do this.

check work

Now I like to check my marks by again feeling for TDC. Your two marks should closely line up.

point start to open

After I have the timing set I move on to the points gap. As the two timing marks start to approach one another I look into the flywheel window and i can see the points just starting to move.

should be about here

A quick peek at my marks show the flywheel mark just starting to pass the grommet. It is at this point that the points start to open and the plug will fire. Since we set our at 1.5mm and TDC is our red mark, the ignition is firing at 1.5mm before TDC. This is the best, stock, power making, last forever setting for plain jane 33mph riding your will want.

widest open

What I am looking for is the point of movement where the points are at their widest open. Oddly that point is when the points are almost out of sight from the window.

cut some gauges

Stock point gap is going to be 0.4mm. I have found that the cardboard on most chip boxes is between 0.36 to 0.49mm thick. For a poor man this will do nicely for the ball park. Remember we are just trying to get this bike popping and smoking down the street to build our confidence. Smooth running will come with experience.

snug fit

When you feel you have the points open at their widest, try to insert your chip box feeler strip between the points contacts. If set ok the strip should slide between the contacts snugly with some resistance or dragging feel. If the strip wont fit or you cant feel any dragging, the points are too close or too wide. You will then need to loosen the points set screw and fiddle with the gap.
Try all of these poor mans techniques and then check your plug for fire. If you have none check everything again. If set like I described you can check off points and timing as your no spark issue. Good luck.

I am now finished with this Wiki page. If you have any questions about the tips I suggested, or are having trouble with the process or can suggest how I can correct a mistake I have made or to make the page better, contact Cheetahchrome