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i've just finished building my first ever lambretta engine and feel warm all over. However...............................

(there's always a 'however').

The clutch seems extremely stiff to me.

I have set it up so that when compressed with a clutch cpmpression tool I have about 1.3mm of free play. I have 5 x surflex plates, 3 x 1mm steels, 1 x 1.5mm steel and a 2.0mm top steel. All nestling in a deep crownwheel.

After I put the side case on, I tried operating the clutch arm and can only get around 10mm of movement (at the trunnion position) after the cam has started to depress the clutch. It really hurts my soft office-worker hand to do this.

Is this normal?

By the way, isn't it pretty? My wife deosn't think so

Is the engine cabled up in the frame?
There's a big leverage factor by using the errr lever, as opposed to pulling the one on the chaincase,
Sorry if I've misunderstood your post.

Scooterlam wrote:Is the engine cabled up in the frame?
There's a big leverage factor by using the errr lever, as opposed to pulling the one on the chaincase,
Sorry if I've misunderstood your post.

You've understood me perfectly, and yes obviously you're correct, but I won't have it in the frame until February so I can't check it properly.

It seems stiffer than I'd expect. Just wondered if anyone could give some guidance as to what I should expect.

Just had a thought. I'll try the clutch arm on my triumph as a comparison. Totally different motor and gearbox but both use cable clutches.

Scooterlam wrote:Is the engine cabled up in the frame?
There's a big leverage factor by using the errr lever, as opposed to pulling the one on the chaincase,...

I agree with this. You can't, in my opinion, simulate clutch action without it being fully connected up to the lever and in an operational engine with oil flow around the plates.

All you can do on the bench is make sure the plates separate properly which I think you have already done.

You can replicate the effect of the lever,
if the end of the lever travels 50 mm to give you 10 mm at the chaincase, this is a leverage factor of 5
find a tube that fits over the clutch arm and mark a point 5 times the length of the arm then pull from that point.

This all works in my head, the figures are picked at random so you will have to measure.
as ever I could be wrong but im sure some one who attended school a bit more than I did, will put me right.

ps find something else to occupy your time as idle pondering has lead to many unnecessary engine strip.

IMO your clutch is going to be stiff on the bench. I can barely pull it in when the engine is not running but when riding, and with gloves on, it's much easier. It's not like a Vespa clutch that you can operate with one finger.

Beg to differ,

Scooterlam wrote:Beg to differ,

I've got uprated Malossi springs on it but even with standard springs I've never had a light clutch like on a PX?

clarification.
all my Lambretta clutches are the same running or not,
My AF clutch is a one finger clutch.

Scooterlam wrote:You can replicate the effect of the lever,
if the end of the lever travels 50 mm to give you 10 mm at the chaincase, this is a leverage factor of 5
find a tube that fits over the clutch arm and mark a point 5 times the length of the arm then pull from that point.

This all works in my head, the figures are picked at random so you will have to measure.
as ever I could be wrong but im sure some one who attended school a bit more than I did, will put me right.

ps find something else to occupy your time as idle pondering has lead to many unnecessary engine strip.

pivot to nipple centre on lever versus nipple centre to end of lever is a ratio of around 4.5:1, so you're guess was pretty good. I added a lever to increase length by around 4 or 5 times and could pull it easily and also could easily turn the flywheel with one hand while keeping the rear hub staionary with the other. I have lots of hands.

I have now decided to continue with the rest of my restoration as per your advice. I just want to renew my inlet gasket and maybe just one more thing......................

Scooterlam wrote:ps find something else to occupy your time as idle pondering has lead to many unnecessary engine strip.

Just stripped the gearbox as I had a nagging doubt that I'd forgotten to fit the layshaft oil-seal.

Turns out that I was right to!

Did you rember to bend the tabs on the clutch locking washer.

Scooterlam wrote:Did you rember to bend the tabs on the clutch locking washer.

Unfortunately I did so now I need a new one. I never reuse things like that.

well done fella.....just stripped my 1st engine down, casings at paint shop....then big head ache starts...lol