Kick start not engaging properly

[Pompeydave]

Just a few teething problems left before I unleash my long awaited (8 years) Quattrini kit onto the roads. It starts so easily largely due to the very good quality Vape ignition. However, when kicking it over the kickstart teeth don’t engage very well with the first gear cog, and it’s always ‘jumping’ where it partially engages then slips and the lever goes all the way to the bottom of the stroke without engaging at all. Every third kick it will just engage at the bottom of the stroke.

It’s a GP setup without the ramp inside the cover. Excessively worn kick start piston maybe?

[Warkton Tornado No.1]

Just a few teething problems left before I unleash my long awaited (8 years) Quattrini kit onto the roads. It starts so easily largely due to the very good quality Vape ignition. However, when kicking it over the kickstart teeth don’t engage very well with the first gear cog, and it’s always ‘jumping’ where it partially engages then slips and the lever goes all the way to the bottom of the stroke without engaging at all. Every third kick it will just engage at the bottom of the stroke.

It’s a GP setup without the ramp inside the cover. Excessively worn kick start piston maybe?

Possibly, though it occurred to me that as the (weaker) gearbox spring has often had the (stronger) kickstart spring substituted which makes gear selection all but impossible, perhaps you have that scenario in reverse

It’s likely you’ll have to investigate, in which case check the register pin & the end plate ramp are working in harmony as well as the clutch pressure plate is not fouling. I’ve rarely stripped an engine - not built by me! - to find that the pressure plate hasn’t been grinding itself on the kickstart……

[Fast n Furious]

Check for excessive wear in the brass kickstart shaft bushes. There should be negligible clearance here.

[Pompeydave]

Ok, thanks chaps, will do all that has been suggested and will report back.

[Pompeydave]

Update. Couple of issues found. The kickstart piston is chipped and very secondhand. Can’t believe the builder used it. Not impressed. Also found that the piston spring is very weak and that he’d put a nice shiny MB 1.8mm Endplate shim in which only leaves 0.4mm excess movement. Doubly not impressed.

The kickstart shaft itself is fine and has been machined down slightly to allow for clutch clearance.

New MB designed piston, spring and 2.2mm shim ordered. Will update further when they arrive and I’ve fitted it all.

[Fast n Furious]

If the current endplate clearance is 0.40mm then by increasing the thrust shim thickness from 1.8mm to 2.2mm will add-in an extra 0.40mm giving you no clearance at all.???
Ideal thrust clearance should be around 0.15mm. A 2.00mm or 2.10mm shim is more like what you need.

[Pompeydave]

No that’s 2.2mm excess movement over and above the recommended minimum, so a 2.2 shim should be spot on. Maybe

[Pompeydave]

The previous post got me thinking, so I measured it all again and the excess clearance was even worse than I thought. I ended up fitting a 2.6 mm shim to get the clearance down to 0.17 mm. Couldn’t quickly get a 2.7 shim to get right down to the minimum recommended clearance, but with the additional new piston, spring and a much thicker kickstart lever it’s transformed to a really nice precise action now.

Dyno’d it and it’s pushing out a full 30bhp, which is impressive for a standard Quattrini. The huge new SIP pipe seems to make a big difference. All good for Kelso hopefully.

[Pompeydave]

Quick update, all good with kickstart and the Quattrini got me to Kelso aok.

[Fast n Furious]

[Pompeydave]

….and got me home again. However, the end can broke off coming up to the Winchester roundabout at the bottom of the A34. Managed to bungee it back on and limped it home via the backroads for the last 18 odd miles.

Am I right in thinking that most exhausts have an end can PCD bolt spacing of 54.5mm? No info shown on the SiP site.

[Fast n Furious]

Circa 55mm is a common PCD for a lot of can ends.

[Pompeydave]

Ok thanks. Bought it 9 months ago so should still be covered by guarantee. Maybe.

[Warkton Tornado No.1]

Ok thanks. Bought it 9 months ago so should still be covered by guarantee. Maybe.

The words ‘Lambretta’ & ‘Guarantee’ are identical in that they have the same number of letters, but as far as anything aftermarket is concerned, the small print may as well say:

‘Removing any goods from the packaging renders any warranty void’