Motobecane cady performance

I have a 1975 motobecane cady that is giving me performance issues. I tore down and cleaned the carb, replaced the spark plug and swapped in a different ignition coil. However it runs fair for about 2min then will "bog down" and lose power and eventually stall. I thought that it might need points cleaned and or condensers replaced but I am not sure. If so....can the points be accessed with out special tools and how? Where can I purchase new points/condensers if necessary? What other problems should I look for? My son has been working on this bike and is getting frustrated.

Thanks

Re: Motobecane cady performance

if a bike runs fair for any length of time, spark, carburetor, and compression must be pretty much ok. If a problem then appears for no reason it would seem to point to some sort of fuel supply trouble.. The engine probably hasn't had time to get really hot so heat related things might be safely ignored...

At low speed, there's nearly a 2-minute supply of fuel in the float bowl.. I'd go through the whole fuel system, top to bottom, and look for some sort of restriction or blockage.

Re: Motobecane cady performance

Yep, sounds like blockage in the fuel system.. plugged up filter, possibly the screen on the petcock.

Have you also tried to run it with the gas cap off? There is a vent in the cap, and if it's plugged, you will have no end of crazy issues.

Re: Motobecane cady performance

Like the others said, it's probably not a spark issue, but here is the answer to your question about accessing the ignition without special tools: NO! I have a Cady myself and I had to buy a clutch puller for 30 dollars just to access the ignition and I need to find or build a cam puller just to set the timing. Good luck with yours!

Re: Motobecane cady performance

How to remove the cam from a Cady:

Although it looks like the cam might be threaded into the shaft, it's not. It pulls off. If you have

the special motobecane cam puller,then it'st easy. Their puller threads onto the outside diameter of the cam, and then lets you push on the shaft.

Here's how I did it, I should have taken a pic, but didn't as I doubted that it would work.

First you need the following:

hacksaw, about a 2 inch diameter brass washer or nut. (the ideal size is used for plumbing, on the drain end). They're very common and cheap and easy to cut. The ID of the washer/nut should be smaller than the cam OD. a clamp (steel strap, screw type, used to clamp hoses and their

attachments) and a standard 3 armed cam puller.

OK, so you take the washer/nut and cut a piece out with the hacksaw. Cut out enough (about 1 inch) to allow you to slip it onto the the cam shaft from the side. Once you've slipped the nut/washer on the camshaft, it gives you a surface for the cam puller to grab on to. Before using the cam puller, clamp the OD of the nut/washer tightly, so that the nut/washer doesn't expand and slip off the cam while you're pulling.

Then position the cam puller to grab onto the nut/washer, turn it with a wrench and watch out. It loosens with a big bang and the whole setup can fly out a bit.

Then you have to replace what you need to and set the timing.

Setting the timing isn't much fun either. It's done by positioning the cam. Each time you position it and measure the timing delay, you may have to reuse your pulling contraption. But each time it comes off a little easier.

I have the manual that has pictures and instructions of how to set the timing. If anyone needs it, just email me and I'll make and send you a copy for a few bucks).

Thor

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Re: Motobecane cady performance

Allthough this problem does sound like a plugged gas cap hole to me, It may be the condensor. They can fail when hot after 30 or so years.

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