holty wrote:i would say as others have that pictures 1 and 2 look a little weak, you say they where uphill so i presume at full throttle, your needle will have no effect at that throttle position i would think, my suggestion would be an increase in main jet size, if it bogs at full throttle its too rich, i melted a piston on the way home from whitby this year, turned out i was way underjetted and yet my plug chop didnt look bad at all, probably my fault as we dont have any hills here to realy load up the engine. im sure you know a little rich makes less power but helps to keep your engine cool and safer from detonation, better than an engine rebuild. your 3 and four pics around your house i presume half to threequarter throttle will be using the needle and idle jet hence your lifting the needle has got a better colour than uphill.other thing to say is i presume you have no air leaks, eg inlet manifold or carb rubber base gasket,mag housing etc as this will make it run weak as well.
best regards,
holty
Thanks for the info Holty. I have moved the clip down to the lowest position and this makes it too rich, un-rideable, so I have it back on 2nd clip up. I have increased the main jet to a 320
Lambretta Series 2 Rat - RB260, SuperTourer, Cyclone 5 gearbox 😎👍
alanscottj wrote:................. I have moved the clip down to the lowest position and this makes it too rich, un-rideable, so I have it back on 2nd clip up. I have increased the main jet to a 320
You could try putting it back up one clip but with a very small dia. washer under the clip. The washer will need to be small enough to fit inside the recess that the clip sits in I'm assuming it's a PHBH but principle holds good for other carbs). That will give you a 1/2 way position (fine tuning)
