Quote:
Originally Posted by Dukedesmo
....the vertical cylinder carb intake is directly behind the rear wheel and facing forwards!
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Can't work out where your carb is DD... I am assuming you mean the front wheel?..
I remember reading (sampling) Phil Irvin's "Tuning For Speed" many years ago, although much of it is still very relevant.
There is a section on the shape of the carburettor intake. The shape of this is critical according to Irvin. We used to call this a Bellmouth, but I believe they go as trumpets or stacks these days? (Shortened from Velocity stacks I assume?)
The bellmouths used to just be bare naked out in the breeze in the olde days, but the shape is just as important whether it is in an airbox or inside a clip on filter.
Nashers filters look like there is enough room inside for a nice bellmouth?
An airbox or plenum chamber does a lot of work (worth a whole chapter). It modifies the air flow into a nice ready supply of clean air, at the correct pressures and volume, all lined up nicely for the carb(s) to easily digest.
There's an awful lot going on in there, which, without going into any detail, contrasts vastly from simply snatching whatever air is passing in the turbulent slipstream.
I reckon if you can afford the filters some kind of shelter, so that they draw from relatively still air, (without robbing the heads of cooling air) and make sure there is room in the filter for a nice bellmouth without fouling it, then you should be on the money.
My money would be on an airbox though.