This customer wanted a GT 250 to the same spec as my own GT 250. The build was on a mint TV 200 casing and included the following parts:
- GT 200 bridged barrel bored to 71mm and ported
- 62/115 crank
- H2 wossner piston 71mm
- LTH clutch
- Cyclone gearbox at 4.7 final drive
- Electrext ignition
- Fran race exhaust
- 30 phbh carb
Case work
Crankcase mouth
Cutting the case transfers to match the barrel and creating a trench for the big end on the 62 stroke crank
Left transfer
Cutting the case transfers to match the barrel and creating a trench for the big end on the 62 stroke crank
Right transfer
Cutting the case transfers to match the barrel and creating a trench for the big end on the 62 stroke crank
Trench
Cutting the case transfers to match the barrel and creating a trench for the big end on the 62 stroke crank
Mag to case
Matching the mag transfer cut to the case
Mag to case
Matching the mag transfer to the case transfer
Barrel work
Porting
Marking up the ports for cutting
Marking up the ports for cutting
Marking up the ports for cutting
Porting
One side cut
One side cut
Both sides cut
Lifting the boost ports
Main cutting done
Stating to polish
Polishing
Piston mods
piston
Marked up for reed window
Piston
Piston on for marking up for cutting.
piston
Reed window and arc cut
piston
reed window cut
Head work
GT 250 head
Head re-profiled to the H2 piston and squish band adjusted. The red plug can be removed and a center spark plug used.
Other images of the build.
Timing
Setting the timing with dial gauge.
Electrex ignition
Nice rear end
Cyclone 5 speed
4.7 final drive
LTH clutch
First start up video and first test ride video.
GT250 special
1st start up. The vibrations that can be heard are the back of the frame loop.
Picks up well and spits nothing out of the carb mouth. So far so good.
11miles on the motor
Running in the new GT246 special.
5 speed cyclone gearbox
LTH clutch
Electrex ignition