Effect of humidity and air temperature on carb performance

[storkfoot]

I have never recovered financially from the amount I spent on fuel and jets trying to get this carb set up. Never ever again. Dell’orto and Mikuni ever since.

[Adam_Winstone]

Been there with a number of carbs and is why I like to get somewhere near, then take it to Readspeed, saving me in the long run.

[Warkton Tornado No.1]

I suppose that I have my most familiarity with Dell'Orto carburettor's, principally VHB's & the VHBC's.

Saying that, the PWK's have been an absolute doddle to set up IMHO, on both reed & piston ported engines. They seem very filter friendly as well, which in itself is a fuel saver, it not being lost to atmosphere, or a trouser leg.....

I think there has been a lot of prejudice against them, but have found that given care to set up to the information widely available (not necessarily on Lambretta Forums) they function well.

One of the most important modifications to avoid the float bowl removal is the easy slotting of the bowl to allow the pilot jet to be accessed with just the drain plug removal. Once set, the float level should never need subsequent tweaking.

They have no tendency to flood & the hot starting problems prevalent with the VHB & PH ranges, as they have an anti-flood tube built in.

The only downside I can think of is that it is best to fit an in-line filter, but that is quite common practice with other carbs using the Lambretta fuel tank filter.

[Adam_Winstone]

I was hoping that the G needle would have arrived before the weekend, however, the H needles + 8-hole atomiser have certainly helped. Sorry that I've not got more to report at the moment but the bike is certainly becoming more rideable.

Cheers for now.

[tavspeed]

i ran a pwk ,think it was a oko from scootrs,for years on a cast 200 top end,scorpion exhaust,didn't know much about jetting then,but put a 115 main in,think i was lucky,because i hit the sweet spot straight away,and thrashed it mercilessly,keeping up with the ts1's,never let me down,and did high forties mpg

[Warkton Tornado No.1]

i ran a pwk ,think it was a oko from scootrs,for years on a cast 200 top end,scorpion exhaust,didn't know much about jetting then,but put a 115 main in,think i was lucky,because i hit the sweet spot straight away,and thrashed it mercilessly,keeping up with the ts1's,never let me down,and did high forties mpg

I reckon that they are the best VFM 'proper' carb for a two stroke that you can get @ 'our' level.

I bet you never had any problems with hot starting for one thing, & they take to a good air filter without any issues, principally because of the float overflow built in.

I read in horror of drain holes being placed into elbows when bellows are fitted to PH carbs to get round their hot flooding issues. Jeez! That's unfiltered air & muck getting drawn in! Do the same people have an overflow fitted in their bath or drill a hole in the base?