hard to kick start 1963 LI 125

[kennystag]

Hi All,
I have to put my full body weight on the peddle to turn the engine over it is really hard to turn it runs fine when started with no funny noises it has been like that since I have had the LI 3 years any idea to what is going on.
Cheers Stag
Skye

[Rich Oswald]

Is it a standard top end? If so the compression shouldn't be that high. You get higher compression with kits on but if set up right with the correct cylinder head profile and the correct squish then it should be quite usable. It may just that your squish is too small and may need a thicker head gasket. Could be many things really.

Rich'

[dickie]

Is it a standard top end? If so the compression shouldn't be that high. You get higher compression with kits on but if set up right with the correct cylinder head profile and the correct squish then it should be quite usable. It may just that your squish is too small and may need a thicker head gasket. Could be many things really.

Rich'

Using LI125 gearbox and standard sprockets with larger capacity but similar exhaust timing makes for a really hard to kick over motor.

Basically, you're trying to do about 50% more work by going to 186 (casa or scootopia) with low exhaust ports. Changing to LI150 box or fitting a 17 tooth sprocket is usually enough to do the trick.

[HxPaul]

I have a Casa 185 with an li 150 gearbox,with 46x16 sprockets and its nearly impossible to kick start.

[MickYork]

Try a diet of Kebabs and donuts...….works for me

[dickie]

I have a Casa 185 with an li 150 gearbox,with 46x16 sprockets and its nearly impossible to kick start.

Have you measured compression ratio?

I've just done 2 scootopia 185s with LI150 boxes and 16 x 46 and they were good.

I think the scootopia is a very close copy of the casa.

[Stapsie]

I have a Case 185, li125 gearbox, 46 x 17 sprocket and kicks over fairly easy. And I'm only a lightweight.

[kennystag]

I am a heavy weight and it is murder @ 19 plus stone.
Stag
Skye

[Hammer]

I’ve got a similar problem, Casa 185 kit li 150 gearbox on a series 3. It kicks ok but it’s very firm and I am concerned for the kick start shaft which is also an li shaft. I’m considering 3 mods at the moment:

1. Upgrade the kick start shaft to gp.
2. Change front sprocket to 17, although I don’t want to mess with the gearing.
3. Drill a decompression port from the exhaust port to the cylinder. Quite radical but I hear it works well.

Any feedback on these greatly appreciated.

[dickie]

I've never had anything to do with the casa 185 kit, but I hear the scootopia 185 is a copy.

Based on that, I'd change the front sprocket to 17. I've done 2 LI150s this way in the last few months and they both go well. They don't feel over-geared at all.

[MickYork]

How free is it with plug removed ?

[Hammer]

Flicks over easy without the plug.

[Hammer]

I’m tempted by the sprocket change as it’s easily reversible. It was the overgearing that concerned me.

[kennystag]

Hi All,
I forgot to say it turns over freely with the plug removed.
Stag
Skye

[Warkton Tornado No.1]

Hi All,
I forgot to say it turns over freely with the plug removed.
Stag
Skye

Ha

Better late than never.

You're not going to like this Kenny.

You need to strip the top end & measure the cylinder head volume. The compression ratio is almost certainly way too high.

It'll be a good thing to do, getting a reasonable CR & the squish spot on. The 'bowl' in the head will need it's volume checking & some extra volume 'added' by removing some of the alloy with a flap wheel/Dremel type tooling.

[Andyf]

Would a 1mm head gasket work as an alternative?

[Warkton Tornado No.1]

Would a 1mm head gasket work as an alternative?

I've had a PM from Kenny & replied.

I would never use a head gasket. In any case, squish is so important to get right, he may get closer to the desired 1.0 mm with none fitted, but no getting around the CR which is too high & needs correcting.

The engine will be so much better for doing it all correctly.

[vegansydney]

I have a Casa 185 with an li 150 gearbox,with 46x16 sprockets and its nearly impossible to kick start.

Is it a pre-2015 'version 1' Casa 185? Or is it a revised 'version 2' (2015+) Casa 185? The geometric compression ratio of the original V1 heads is 10.8:1 with 1.1mm squish clearance (volume of combustion chamber and squish clearance with piston at TDC is 19ml).

For comparison, does anyone know if compression ratio differs on version 2 of the Casa 185, and how this compares to the Scootopia 185 kits?