Scooterotica

Setting my squish on mugello 186,cant get any reading with the 2 peices of 1.5 mm solder on piston,but an get a 1.65 mm reading with a twist of solder as in stickys book.This reading is with the thinnist of the 3 head gaskets in ,what do you think,any ideas.
Thanks Ian

you need to be as close to 1mm as you can get it. you may need to run no base gasket and no head gasket and just use silicone to get the squish you are after or failing that the head or barrel will need skimming

i just noticed from one of your other threads that you are using a spanish casing and have found that the barrel studs are too short.

spanish casings do differ as you have described by about .8 of a mm. no idea why though.

by how much were the studs too short?

on a similar note,
i,ve just fitted an Imola kit to italian casings......
first thing i noticed was that in some areas around the transfers on casing ,.there was only approx .5mm of width to seal base gasket,
and so the casings had to be modified to provide a descent seal..

also the studs were not long enough either..

then ,even though 3 head gaskets of different thicknesses were suplied with the kit..
it was found that by not using any head gasket at all...the minimum squish was 1.84mm..

maybe its "the flexability of sandcasting" that makes each kit with radicly differant sizes and port timings

How will it run with a squish of 1.55 mm,is it safe to run without a base or head gasket?.
Cheers Ian

It will run with a squish of over 1.5mm just it wont run at its best. As said already 1mm is perfect, less than that and there can be problems with the piston touching the head as the con rod stretches and tolerences are taken up in the bearings are taken up.

Sean how did you modify the transfers? with welding or the use of chemical metal type of stuff or epoxy putty?

i used devcon on these,i think.
Mick abbey gave us it to try ,in unmarked tubs,but it sure looked like it..
it took about 24hrs to harden fully.......but then it really was rock hard....and could be filed into shape...

They have a two part epoxy here that the alcohol dragster people use for flowing heads. Made by Edelbrock. Have to heat with a blow touch to set it up. Spendid stuff. A whitish/yellowish color.