Removing SU Carb, cleaning and replacing.

[ROBBIE]

So why would I want to change the needle?

if memory is right it help with fuel mix

[ROBBIE]

http://www.jetlink.net/~okayfine/su/hs4partsguide.pdf
try this link it gives an exploded view

[Pugsley]

So why would I want to change the needle?

Also I have cleaned it all out using petrol, is this ok? Are there any No No's when it comes to cleaning it out etc?

Im also not sure about the gaskets etc, should I be using some sort of sealant stuff or grease along with the gaskets?

Grease around some of the parts on the carb?

Also the washers that grip round the bolt these dont come off and and go back on easily, so do i need to replace these?

Sorry for all the questions, just that i am going to rebuild today so want to get hold of lots of info.

Thanks

Cleaning the carb with petrol is fine - make sure that it's clean! Carb gaskets should be fitted dry without sealing compound. Unsure what you mean by "the washers that grip round the bolt". Finally - SU carb needles are designed so that the taper (thickest at the top) conforms to certain measurements, I can't recall exactly how many times along it's length a specific dimension is stated but it's about 10 or so. Each needle is coded and if you remove your needle and look on the side of the shoulder it will have 3 letters stamped on it e.g. AEM, DRA etc. These denote the dimensions of the needle and its degree of taper. As the needle is raised or lowered in the jet in which it sits by acceleration or deacceleration, the jet hole is partially uncovered by the tapered needle allowing a given amount of fuel to be passed to the engine. Different engines require different fuel requirements hence the availability to change needles, but don't go wasting money on needles when you don't know for sure that yours is unsuitable or perfect.