Jawa? identification

[ola_martin]

What is this??
2V 4V? Year?
Framenr: N 0280
http://s1222.photobucket.com/albums/dd485/ola_martin/MC1/?action=view&current=Jawa.jpg

[jimg1au]

CENTER PORT FRAME 4V

[jimg1au]

a lot of different motors can go in this
weslake
goddon
gm
sell it to and i can put my center port honda motor in it
jim

[ola_martin]

Thanks, great
What year ca. is it?

[jimg1au]

i dont know
 if it has a steel wheel on the back it is made up of different years
it has a 6 spring clutch as well
jim

[ola_martin]

where the frames the same for many years?
When did they use centre-port 4v engines then?
I mean just roughly. I know nothing about speedway...

[jimg1au]

center port 4v speedway motors about 1980
check this link out

http://www.vft.org/RouitMuseum/Gallery/Speedway.html

[ola_martin]

Thanks.

[Dutch]

http://www.eurooldtimers.com/
This is a Czech site, but maybe usefull if you use the English translator.
On this site are many Jawa Speedway / longtrack bike by year

[VMX247]

bump~ nice link info here !!