Screaming Ciao

I have a '74 Ciao. It runs great but when I try to go up a steep hill, or sometimes when I accelerate from a stop it makes a terrible screaming noise. I'm thinking it could be the centrifical clutch or the belt what do you think? has anyone had this problem?

Re: Screaming Ciao

maybe it's afraid of heights or going fast.

But seriously folks, could be several things. Does it make teh "screaming" noise when it is on the center stand with the rear wheel off the ground when you throttle to high rpms? If it doesn't, maybe rules out engine bearings.

Check the rear final reductiion gear for oil. This sometimes gets missed, It takes 90 weight gear oil. Left side of rear hub for access screw.

Check belt tension

Check front pulley (clutch if single speed or a variator if variable speed model).

If it is a variable speed it has a big starter clutch rear pulley.

If it is a single speed model it is a regular pulley.

Are you using a 50:1 mix (2.5 ozs /1gal of gas)? Are you using a good grade of 2 cycle oil (not weed wacker oil)

Re: Screaming Ciao

Jeremy West /

it does not make the screaming sound when it'a on the stand. It only makes the sound when the engine is under heavy load like accelerating from a stop sign or going up a steep hill. If I decrease the RPM significantly and accelerate or climb very slowly the sound stops and once the ped get's up to speed the sound stops. I originally had a problem with no power that turned out to be a loose belt. I've tightened it as much as I can. Could it be too tight? The sound it makes is like a car with a loose belt that screams when the engine is cold. What would you recommend to clean up the clutch, it's a single speed, not variator, as it seems the shoes may not be gripping well? BTW this is the 20mph model.

Re: Screaming Ciao

The belt could be too tight (not good for the engine). Do you have the correct belt for the bike?

The proper way to check belt tension is to measure out on top of the belt, 12.4 inches from the middle of the rear pulley. At that 12.4 inch point you are supposed to hang about 4.4 lbs weight from the top belt. The belt should have about 1/2 inch of downward play if it is adjusted properly.

If the original reason was for tightening the belt to the max was lack of power, then the main clutch shoes may be worn and need to be replaced.

While we are talking about clutch shoes, another common mistake is to install the starter clutch shoes backwards. If you have the clutch assembly off and looking down into the clutch, the starter shoes should be at the 7 oclock and 1 oclock positions, so they spin outwards properly when you pedal.

If you need new starter or main clutch shoes you can order them from the Vespa Super Shop in San Diego.

Have you ever had the clutch off? There is a little spacer that goes on the shaft before the clutch goes on the shaft. It is shaped like a little hat with a brim. A mistake people sometimes make is to put this on backwards with the top of the hat pointed toward the engine. It should be with the brim against the engine side with the top of the hat pointed outwards.

You can clean the clutch shoes with brake pad cleaner. You can also use emery paper to remove the glaze a bit and have more of a rough surface on the clutch pads. Also lighty grease the pivot points where the clutch shoes are secured but don't over do it.

Take a look at the rear pulley by standing behind the bike while it is on the center stand with the engine running and see if the pulley wobbles excessively.

Don't forget to check the gear oil in that rear hub for the final reduction gear.

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