1979 motorbecane

Wondering if anyone has any idea. Bought this moped knowing it didn’t run but that maybe just top end or something. When I spin the vareator side outer part or inner the piston doesn’t move and when I spin the other side the piston moves. Even if I pedal like crazy and I see the clutch side moving in to the belt the other sides just sits there ?? Pulled the vareator off and it looks ok but I bought new clutch pads and new starter clutches for it but I don’t think that’s the issue. I was going to pull the other side off because one person said there is a key way that probably broke but then others say there is no key way. When I put the puller on the right side and just snugged it up it seem to spin both sides.

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Re: 1979 motorbecane

You need to read a manual, ProjectMopedmanual has what you need.

Re: 1979 motorbecane

Well a little help why it’s doing that would of been nice if you know what is wrong. Been reading everywhere and can figure it out

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Re: 1979 motorbecane

When you first remove the cover you will see the two starter clutch arms inside the clutch housing and the 3 or 4 main clutch pads on the sides of the cover. The arms are what actuates to start the bike and the covers pads are what drives it.

Check that the starter arm's pads are not worn out, otherside you need to replace them or glue on new friction materials.

Disconnect the little springs on the two arms and make sure the arms can move freely - like really freely - otherwise use some penetrating oil to loosen them up. Once they are floppy loose reconnect the springs and use some brake cleaner to get rid of the extra penetrating oil so it is not chased onto the pads and mess up the clutch.

On the inside of the cover make sure there is no surface rust on the area that the starter clutch pads need to go against to start the bike.

Also check that the decompressor valve is actually working when you squeeze the lever... not always mandatory but it helps.

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Re: 1979 motorbecane

The clutch pads and starter clutches look good but I bought new ones anyways. When you spin the clutch side it just spins freely. When the clutch was on it did grab the belt but still nothing. When I spin the right side the engine turns over( piston moves ) I’m just baffled. There’s some pictures on one of the post.

Re: 1979 motorbecane

So is it normal for the clutch side shaft just spins freely and doesn’t move the other side but when you spin the other side it spins the clutch side.

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Re: 1979 motorbecane

Until there is sufficient speed in either the motor when running' or the pulley if starting, the clutch/variator assembly will rotate freely on the crankshaft. The clutch cover is fit with a taper fit to the crankshaft on the PTO side and should have a excellent grip on the PTO side of the shaft.

The magneto side of the shaft has the flywheel which contains the exciter magnets for the magneto as well as providing some weight to keep the motor rotating smoothly. This is firmly held in position by the Novi nut to the ignition cam. The ignition cam must have a excellent grip on the magnito side of the crankshaft in order to maintain correct ignition timing.

With the engine running, the PTO side of the engine drives the cover of the clutch, the clutch drives the variator via the 3 or 4 shoes on the periphery of the cover. When engine speed is high enough for the weight of the friction material on the shoes chases out by centrifugal force and contacts the bell of the clutch housing.

Starting the engine the pedals drive the rear wheel which drives the large pulley, if the pulley switch is in the 'Moteur' position (Velo position disconnects the small gear from the pulley) then the large pulley drives the variator side of the clutch. When the speed of the variator/clutch assembly is high enough for the weight of the starter arms the friction material will contact the inside of the periphery of the cover with sufficient force to turn the cover and rotate the crankshaft.

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Re: 1979 motorbecane

Well change the starter clutches and changed the four outer pads and I pedal like crazy and still the other side doesn’t spin. I watch videos and they start them pretty easy

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Re: 1979 motorbecane

Dumb question, but is the engine switch on the engine mode, not pedal?

Re: 1979 motorbecane

It really kinda sounds like it’s in bike mode, not motor mode :)

Re: 1979 motorbecane

Yes for sure. Lol. Has spark turning over the other side. All new clutch pads and still pedal like crazy and the other side doesn’t move. First Moby for me and all ready hating them. I restore mopeds as a hobby

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Re: 1979 motorbecane

No because when I switch it just the bicycle moves but I thought that as well. Totally baffled. I restore mopeds as a hobby but never done a Moby

Re: 1979 motorbecane

So its a weird question... The inner...part...should spin the crank? i believe? what I would do: make sure the variator is in place, circlips, etc. Make sure the belt lines up and the variator nut is tightened to correct torque, 18 ft lb. On the stator side, did you set the ignition timing correctly? often more than once. And Novi nut tightened, 30-36 ft lb. And lastly, no air leaks, good fuel delivery, and that nothing in electrics is causing anything.

Re: 1979 motorbecane

Think all is good. If I spin the other side I get a good zap.

Re: 1979 motorbecane

How about a good close up picture of the clutch, if you replaced the arms and they are very free to move on their pivots there must be something else incorrect.

> Brian Terrell Wrote:

> -------------------------------------------------------

> No because when I switch it just the bicycle moves but I thought that as

> well. Totally baffled. I restore mopeds as a hobby but never done a

> Moby

Re: 1979 motorbecane

Even before I replaced the clutches it was doing the same thing. The starter clutches move easy when the springs are off. I thought the clutches were my problem. They looked fine but I replaced them anyways

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Re: 1979 motorbecane

The rivets for the main clutch pads are backwards, should be installed from outside so that after you buck them good and tight you can blend them into the face. Right like this the poor starting pads are trying to grip at a surface with rounded blobs on then so it will be hard for them to grab well.

The main clutch pads also look pretty one for so may want to replace them as well. The stock rivet sizes are 3mm or 4mm depending on the holes in the cover.

> Brian Terrell Wrote:

> -------------------------------------------------------

> Even before I replaced the clutches it was doing the same thing. The

> starter clutches move easy when the springs are off. I thought the

> clutches were my problem. They looked fine but I replaced them anyways

Re: 1979 motorbecane

I grinding them flush since that picture. The other pads are new but it was tight because of the thickness of them so I sanded them down

Re: 1979 motorbecane

> Kevin Wayne Wrote:

> -------------------------------------------------------

> So its a weird question... The inner...part...should spin the crank? i

> believe? what I would do: make sure the variator is in place, circlips,

> etc. Make sure the belt lines up and the variator nut is tightened to

> correct torque, 18 ft lb. On the stator side, did you set the ignition

> timing correctly? often more than once. And Novi nut tightened, 30-36 ft

> lb. And lastly, no air leaks, good fuel delivery, and that nothing in

> electrics is causing anything.

Yes this is true.

If you spin the flywheel then it should spin the inner part of the Variator only. It sounds like the inner part of the Variator is not on the tapper. Even if you had the circlip messed up The Variator would still seat on the crank tapper.

Did you take the Variator apart and lube it?

If you spin the flywheel does it spin the Variator side of the crank? (edited)

Re: 1979 motorbecane

Lube where ? Did the crank. Yes if you spin the right side the left side moves too. I was thinking about taking the variator off and hook a drill to it and see if the other side spins at high drill speed

Re: 1979 motorbecane

> Brian Terrell Wrote:

> -------------------------------------------------------

> Lube where ? Did the crank. Yes if you spin the right side the left

> side moves too. I was thinking about taking the variator off and hook a

> drill to it and see if the other side spins at high drill speed

This does not look good

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I believe you are not grabbing to crank tapper on the Variator side.

Did you use a puller to remove the Variator cover or does it just slip off?

Re: 1979 motorbecane

I used a puller to get it off. The section you circled has grease on it. But like I said when I got it I peddled the hell out of it and it never caught to spin the other side. My dad had one back in the 80’s and you could stand next to it and one leg pedal and it fired up. I bought a new belt and clutch pads and still nothing. I don’t want to buy a new variator and get the same results. If I knew for sure I would just buy one.

Re: 1979 motorbecane

> Brian Terrell Wrote:

> -------------------------------------------------------

> I used a puller to get it off. The section you circled has grease on

> it. But like I said when I got it I peddled the hell out of it and it

> never caught to spin the other side. My dad had one back in the 80’s

> and you could stand next to it and one leg pedal and it fired up. I

> bought a new belt and clutch pads and still nothing. I don’t want to

> buy a new variator and get the same results. If I knew for sure I would

> just buy one.

Post a video!

Are you using the decompress? The starter clutch system will not work without a decompression.

Re: 1979 motorbecane

Yes but there is no change ( doesn’t get easier) because the motor is not turning over. When I spin the right side by hand it does get easier using the decompression. Something is just not adding up. If I try the drill and the other side spins the I would think it is the variator. Your thoughts ?

Re: 1979 motorbecane

You need to clean the heck out of the well that is circled in the picture as well as the tapered part of the crank where it should be gripping. If there is grease on the taper of the shaft or the taper inside the well then the two components will not lock together. If they are not locked it will spin.

> Brian Terrell Wrote:

> -------------------------------------------------------

> I used a puller to get it off. The section you circled has grease on

> it. But like I said when I got it I peddled the hell out of it and it

> never caught to spin the other side. My dad had one back in the 80’s

> and you could stand next to it and one leg pedal and it fired up. I

> bought a new belt and clutch pads and still nothing. I don’t want to

> buy a new variator and get the same results. If I knew for sure I would

> just buy one.

Re: 1979 motorbecane

Richard Eberline /

your pedal mode's latch to the gear is bad. Like in neutral, just a spinning. keep switching modes and you might get lucky.

Re: 1979 motorbecane

When I switch it it does go to bicycle mode and only that works and peddles much easier so I don’t think it’s that.

Re: 1979 motorbecane

I’ll try that today and other people say the bicycle switch but that does go to bicycle mode and it’s much easier to pedal.

Re: 1979 motorbecane

Cleaned everything and going to put it back together. The new starter clutch springs are real strong should they be ? Also is anything supposed to be in this hole

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Re: 1979 motorbecane

You should ruff up the inner part of that so the pads got something to grab. I wonder if your starter clutch is not engaging. You should pedal without the Variator cover to see if the starter clutch pads are expanding and functioning properly

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