Originally Posted by Slogger
My engine also came from Duane at Dax. Gen IV.
Taking a look at it I saw it had no head gasket installed. Hm. Then I checked the deck height of the piston, looked at the mating surfaces between the cyl and head, they looked carefully machined.
Put it on the bicycle and it has about 200 miles on it now. This engine has never so much as seeped fumes around the head or exhaust port, or the cylinder to case.
Bone dry. nothing to wipe off.
This was a new expeerience for me, I'd worked on a couple of these before and they all seemed to leak just a bit.
It runs real smooth and starts right up. It's a very good little engine.
I'd buy another one with no qualms at all.
When I talked to Duane on the phone here a while back, he told me he was running his new GT5 platform engine with out a gasket and running the Puch/RT head on it with excellent results, if the surfaces of head and cylinder deck are true and the head nuts are torqued down evenly this setup is gona work just fine on a GT5 or half Breed engine since the piston lacks a few .001"s coming up the the ideal TDC.
For mine I'm just shaving the jug deck until I get piston as far up in the hole as I want it and then use a gasket, but it seems that on these GT5 and half breed engines not using a head gasket is an improvement if you use a head other than the stock kit heads that are known for warping and sometime even giving issue when using a gasket.
The Puch/RT head and several other aftermarket heads we have available these days should work good without a gasket as long as the deck is surfaced on fine sandpaper taped to a piece of glass to get a smooth flat deck so it will seal good.
I'm also a fan of Dax, just hard to go wrong with dealing with him or the products he sells so I promote them.