Ah memories....The bike's a pretty cool Jawa Californian 'modified' for MX. I think I raced against this same bike at Mortlake in the early 90s and it went pretty well considering the puss heap it had evolved from. Don't get confused and think that this is similar to a twin port CZ. Even though they share the same parentage, absolutely nothing is interchangable between the two.
A few years ago Anthony Suttor got a placing in pre 65/250 at the Barabool Nats on of all things a 200cc Bultaco Campera.(ah for the days when we ran not just one pre 65 class but a 250 division as well!). In a fit of drunken bravado I bet him that if he can trophy on a slow old dung beetle like a Campera I could do it on a Jawa Californian.
A clean unblemished Californian was purchased from Brad Lewis and I started the bikes transformation. About 40kg of Iron Curtin mild steel was removed from the frame, CZ forks and wheels fitted, a British alloy tank of some description put in place of the 2mm thick steel Jawa item a Maico seat and generic alloy fenders screwed in place. Then it was time to get into the engine. To get the right drum I rang Newcastle Jawa/CZ maestro Dave Morris to line up some porting and get the dimensions ofr a pair of pipes. Now, Dave is a great bloke, willing to help anyone get another Czech bike onto the track but when I told him of my plans he started pissing himself laughing uncontrollably. Once he calmed down he explained that the cast iron Jawa barrel had the most basic 3 port configuration ever and had been designed in the 1920's and was still virtually unchanged. He explained that it was almost impossible to port the Jawa for any sort of power and that to produce efficient expansion chambers they'd have to be about 8 feet long and 9" diameter at the centre section. In other words, even though thousands of communist comrades rode them to work in the munitions factories every day with nary a hint of drama, to actually tune one to race would be a task of phenomenal proportions.
Disapointed at the news, I sold the bike to Ray Atkins, paid up the bet to Anthony and went back to my beloved Maicos. Methinks this seller is on dream capsules if he thinks he can get 3.8k for this old commo.
As Daryl said in the Castle...''Tell him he's dreamin' son".