LCGB Forums

I am building up the top end on a brand new Rapido and having trouble setting the squish.
Sticky book recommends 1-1.5mm
I couldn't get anywhere near with a gasket but it comes in 1.1-1.5mm (depending on where you measure) without a gasket.
The smallest gasket I have found is 0.4mm, this leaves me with a best estimate of 1.5-1.9mm.
Can you get smaller gasket than 0.4 or fit without a gasket using a high temp silicone?
My worry with the silicone is it spilling into the cylinder

Lap the head to the barrel and use either hi temp silicone or the loctite recommended in Sticky's book.

If using the silicone use enough to seal but don't slather it everywhere, I'm pretty sure that if a small amount does get into the combustion chamber that it'll burn off quick.

Don't forget you can use different thicknesses of base gasket or run without and use silicone. That will have a slight affect on the port timings though but possibly not much.

is your casing a spanish 200?

Indian ones can vary too. Mine was quite high, ended up taking some off the bottom of the Rapido, about 0.75mm I think in the end.

What's the distance between the gasket faces on the barrel? Is it even all round?

Meds wrote:......................I couldn't get anywhere near with a gasket but it comes in 1.1-1.5mm (depending on where you measure)

Are you using the method Sticky suggests with solder in an X form? if not, the piston will rock slightly in the bore and give you varying readings. I prefer to use 4 blobs of plasticene, very easy to measure with vernier and you don't get through so much solder

The casings are indian.
The method I used to start with was the solder x method.
I then used the quick solder down the barrel to get an I About where I needed to go.
I am going to try it without a base gasket and see how it times up then take it from there.
Thanks for the advice.

Thanks for the advice
checked it using the x solder method with the base gasket off, got between 1.1 and 1.2mm with a 0.7mm head gasket.
Rebuilt and set up using some silicone gasket for the base and the squish comes in at around 1.3-1.4 using the solder down the plug method, so it looks good.