25:1 Conversion

[james@cornwall]

Just fitted a 25:1 needle in the villiers carb on my featherweight. I initially set the grub screw level with the piston. The engine started reluctantly, but would only keep running with the choke on. I wound out the grub screw by one turn in quarter turn increments to get it to run without the choke but it is now running very hot. Water is circulating OK. Are there any further adjustments that I should be making?

[Vic]

Odd
Are you sure the jet centrepiece is properly clean and correctly fitted? Retaining screw in slot , not round hole?

Did you touch anything else other than just lift out the piston and change the needle. Spring fitted to the new needle ?

You have changed the fuel to 25:1?

My Featherweight converted to run on 25 :1 runs with the grub screw flush with the top of the piston but to get it to run without 4stroking I have had to screw it down "quite a bit".

[John@sos]

My own 55 needs the screw down nearly a turn to stop the annoying 4 stroking at 1/4 throttle. they are all different....

This one sounds as if it has a fuel blockage, jet? Or... have you drained the 10:1 and refilled with 25:1? just a thought, it does make a difference.

Regards,
John
SOS