This is an Italian GP200 casing, the customer wanted a GT 230 conversion. The engine was in bad shape when disassembled as can been seen in the images below.
This GT 230 conversion consists of:
- 60/110 crank
- AF Wossner 70mm piston
- GT 200 bridged barrel bored to 70.25mm and ported
- Franspeed Race exhaust
- Electrex ignition system
- LI 150 gearbox at 4.7 final drive
- Five plate clutch
- PHBH 30mm carb
Problems encountered when stripping down.
The chain guide was held in with 2 M8 bolts.
Welded and re-tapped now.
Stud threads
Welded and re-tapped
Slidding dog missing a leg.
Bad damage to the layshaft.
Stud threads
welded and re-tapped
Transfers
done badly sometime in the past.
Endplate falling off
The end plate was falling off. I've never seen one so loose. One of the studs had been loose and had worn the hole big enough to put an M8 stud inside. Another had a helicoil that was poking out of the hole by 10mm. . Welded and re-tapped now.
Transfers
done badly sometime in the past.
Other work undertaken
Mag hacked in the past
Someone's had a go at this and failed
Mag
reworked
Mag
reworked
Boost ports
Raised
Exhaust port
Re-shaped and polished
Filings
Some of the material taken out
BLowdown area
Piston mods
The piston used is from a piston port engine so needs reed windows and an arc cutting into it.
Crankcase
Transfers reworked, they are not as nice as i would like but considering the state they were in ......
BDC
Port alignment at bottom dead center