65 AV88: Poor Throttle Response at low speed

My Mobylette Bleu was running pretty decently until recently. However, one problem I NEVER solved was the poor low-speed.

When warmed up, the moped usually had very poor throttle response from low-speed/RPM. I had to open her up very gradually to get her to catch....if I opened the throttle too quickly no response or lag of several seconds....then she gradually caught.....

Once wound up she's fine; this problem does not happen at speed.

Any ideas?

Note: She's stone-stock and will do about 50 mph even with the faring on....

Any advice appreciated.


Re: 65 AV88: Poor Throttle Response at low speed

Set the timing to around 1,5mm BTDC.

Re: 65 AV88: Poor Throttle Response at low speed

Rebel Moby Wrote:


> Set the timing to around 1,5mm BTDC.

I will do it RM, I even have the special tool....just dragging my feet a bit not wanting to go from bad to worse, but I'm fed up with the throttle lag. I will just grab em and do it.



Re: 65 AV88: Poor Throttle Response at low speed

Hi Rebel,

I went ahead and reset the timing with my timing tool. The Mobylette has been in bits for a few weeks as I've been doing some major restoration but finally got her assembled enough for a test. The bog is gone! Normal throttle response.

She seems to have "slightly" less power but this could be my imagination and the fact the spedo is worn and she's been just sitting......

I also replace the exhaust pot, the head gaskets, and the variator, re-soldered the ground wire from the coil to the lug on the engine mount bolt, clean and lubed the chains, etc. et al.....plus the gas in her tank is months old which probably also a factor.....

But in any case, she starts right up an otherwise seems to run TITS! Quieter, smoother than before. I will change out the throttle cable and the rest of the cables later.....I have a feeling the throttle is not opening fully.....

Many thanks again,


Re: 65 AV88: Poor Throttle Response at low speed


Mobys also run better the more they are driven so perhaps she just needs to stretch her legs a little. The Huret speedometers are more of an ornament then functional, even when new.

You would also want to replace the bonding strap from the coil to the engine mount bolt, relocate the engine end to one of the inlet studs for a more positive electrical connection.

Re: 65 AV88: Poor Throttle Response at low speed

This one is so damn old it actually has a Veglia spedo....but same deal. It's steady up to 30kph and then starts bouncing unless the Mobylette remains at a constant speed....

I took her out for 1/2 hour spin on the coast today before I start breaking down the front wheel to replace the rim. Runs much better than before, no throttle lag at all and the "stench" of un-burned gas seems greatly reduced so perhaps that was related to the timing as well. She seems to burn much cleaner.

Since I cleaned the chains as well, broke down the rear brakes and rear suspension, then completely re-lube it all no squeaks and a lot less drag rolling her when not running. I think I'm getting close to "like-new" performance.

Did experience a "very slight" cutout for just an instant once or twice....so again it may be that the replacement high-tension coil under the tank is a lemon.... I will do at least 10 laps around the town (about 15 miles) as a test before I will trust her for longer runs.

I attached a couple snaps before the over-haul and after. Still have not painted the body-work, waiting until I get all the mechanicals finish.

Bien cordialement,



Re: 65 AV88: Poor Throttle Response at low speed

Very nice!

Re: 65 AV88: Poor Throttle Response at low speed

Your bleue is very nice indeed - excellent!

Re: 65 AV88: Poor Throttle Response at low speed

Thanks Gents,

Yes, I'm very satisfied with this moped, truly a piece of industrial art, excellent lines and built like a tank! She's a real pleasure to ride. No wonder they sold millions.....

Still have the 1961 in bits.....but I'll eventually get that one if I don't pick up a Solex in btw....

Regards from France.


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