Search found 1155 matches

by J1MS
Sun Feb 13, 2011 11:01 pm
Forum: Lambretta Tech
Topic: kickstart stops dead/meets resistence at begining of stroke
Replies: 11
Views: 1383

Re: kickstart stops dead/meets resistence at begining of str

Anyone???

Me, I think it will be a problem with the side case assembly, but what it is I don't know.
by J1MS
Sun Feb 06, 2011 11:53 am
Forum: Lambretta Tech
Topic: twisted frame
Replies: 14
Views: 1478

Re: twisted frame

As said Mike Pheonix does a top job... but as said "NOT CHEAP"
by J1MS
Tue Feb 01, 2011 8:34 am
Forum: Vespa Tech
Topic: Exhaust port 65%
Replies: 19
Views: 1978

Re: Exhaust port 65%

So, if I understand it correctly, an exhaust port on a 225 (70mm) barrel which is 45mm across the chord would be concidered as 65% of the bore width and therefore acceptable for a reliable road going set up without resporting to exotic wire ringed pistons? Sorry to labour the point J1MS but your op...
by J1MS
Mon Jan 31, 2011 8:17 pm
Forum: Vespa Tech
Topic: Exhaust port 65%
Replies: 19
Views: 1978

Re: Exhaust port 65%

Port mapping is not what I'm saying but port mapping will give the same width if it's done correctly as measuring across the chord (port edge to port edge) If you do a port map you basically do a rubbing of the barrel from inside the bore. To transfer these measurements you wrap the rubbing around t...
by J1MS
Mon Jan 31, 2011 5:53 pm
Forum: Vespa Tech
Topic: Exhaust port 65%
Replies: 19
Views: 1978

Re: Exhaust port 65%

Across the chord, that's port edge to Port edge.

70% is the safe max for wire rings on an open port (across the chord) without bridges or dog teeth to aid the rings on the ports leading edge.

Normally when talking about port widths using the circumference of the barrel then it's done by degrees.
by J1MS
Sun Dec 19, 2010 5:41 pm
Forum: Vespa Tech
Topic: air fuel ratio on the dyno
Replies: 76
Views: 9862

Re: air fuel ratio on the dyno

Mattsdad has raised a good point with regards to how the AFR's are taken knowing how a four stroke fills the cylinder with very little valve overlap on a fourstroke whereas a two stroke has no check valve to seperate the incoming air/fuel from the exhaust gasses, with an exhaust system designed to s...
by J1MS
Mon Dec 13, 2010 8:57 pm
Forum: Vespa Tech
Topic: air fuel ratio on the dyno
Replies: 76
Views: 9862

Re: air fuel ratio on the dyno

quote Mattsdad...

"true AFR reading becomes distorted. the nature of 2 strokes is inherently one that is not compatible with exhaust gas sensors"

Please could you explain how and why.

Thanks
by J1MS
Sun Nov 28, 2010 10:14 pm
Forum: Lambretta Tech
Topic: boysen reeds
Replies: 6
Views: 639

Re: boysen reeds

.
by J1MS
Sat Nov 27, 2010 2:01 pm
Forum: Lambretta Tech
Topic: Wal Phillips injector
Replies: 21
Views: 5219

Re: Wal Phillips injector

^^^I think it's good to get such feed back, from someone who really knows there stuff.
8-)
by J1MS
Thu Nov 25, 2010 10:52 pm
Forum: Lambretta Tech
Topic: Wal Phillips injector
Replies: 21
Views: 5219

Re: Wal Phillips injector

My mate Kenny Sapper from Liverpool ran one of these on his SX 200 back in 77-78. He spent more time fine tuning and adjusting it than riding it. I think my other mate Ste Rodgers also from Liverpool still has has it in his posession, it got passed about but never really used by anyone. Too much tro...