Vespa SI Slides

[gaz_powell]

Having looked and altered everything in SI carb (caps, needles, filters etc) - i started looking at slides

P200 24mm and 26mm uses 8492-4

T5 24mm uses 8492-5

Found this on the net

The Si 24mm carb. has two types of throttle slide. The Si E found on the PX200 has smaller cutouts compared to the slide on the Si G carb. found on the T5. The throttle slide cutouts allow air to pass through and mix with the fuel at idle. The T5 G carb. with it's larger cutaways allows more air in at idle compared to the Si E cutaway. This will also have some effect on takeoff as it will enable more air in and hence with the jetting, more fuel. This is the reason why the Si G carb has a richer idle jet than the Si E carb.

Reading the above would say that an increase in pilot is required if the T5 slide is used - has anyone done it and what effect ?

Gaz

[goldeneye]

T5"s use a rich pilot (50/100) , so ,yeah , I"d guess you"d have to compensate if putting a T5 slide in a P200 carb. the new PX uses a slide with divots in it (for want of a better word) presumably to lean off the mix for emmisions, or is it the other way round? I messed about with changing slides on a polini 177 with P200 carb years ago, cant remember the changes I did but it cured the flatspot at 1/4 throttle it suffered from. its not something I usually change when doing , say, a malossi 210, but I suppose its another thing to look at (or do ya heed in!)