400ex keihin fcr 39 & 41 mm carb which one to get pros and cons!! HELP

[Quadjunkie007]

Like most of us we strive to go faster and faster wiht this in mind it brings me to a problem. After a complet rebuild on my 400 ex IE 440ex port polsh valves the works I'm in need of a carb. The keihin fcr 39mm or 41mm I have been told both these will work but don't know any one who is used the 41mm yet!!! SO :confused: some input would be great on this It would be nice to know the pros and cons of each Thanks

[plkmonster2]

You won't need the 41. There is probably little to no difference in power. Plus, the 39 is morew common, and thus is cheaper to buy.