-Replaced original top end with an SR cylinder bored to 66mm (total cost incl rebore £60)
-Mahle piston £30
-TV175 cylinder head reprofiled to 66mm using cardboard template and Black and Decker band sander
No cost as it was in the spares box-Original 20mm carb rejetted to SX200 spec
-changed existing box to an Indian Vijay Super which is basically SX150 with a better spaced 3rd gear (again a freebie)
- Inlet and exhaust ports matched with said sander (using standard downpipe and original exhaust which has had surgery in the dim and distant past) Exhaust port raised by 2mm and widened to 42mm
- piston has had 3mm taken off the inlet side, and I've "grooved" the areas where the transfers and exhaust ports are to a depth of 2mm to see what happens)
-Timing is at 20 BTDC and the squish is about 1.5mm. Piston to bore is 3 thou- no piston slap or rattle.
To be honest, my tuning skills are pretty basic, but for the cost involved (under £100) I thought what the hell!! Many purists may be shocked at the cavalier attitude I've taken, but at the end of the day, if it goes "bang" its not cost much and I've enjoyed it.
Its been run it (sort of..........) for 50 miles and the transformation is very good- it will end stop on the clock for mile upon mile and the acceleration is much better (may fit an old 16T front IDC)
Now.........where did I put that Wal Phillips back in 1969!
Chris
