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Old 05-08-2013, 06:25 PM   #44 (permalink)
Master EcoModder
Join Date: Feb 2009
Location: France - Paris
Posts: 762

la_voiture_de_courses - '03 Renault Megane Estate
90 day: 44.34 mpg (US)

xiao lan - '01 Audi A2
90 day: 38.88 mpg (US)

Brit iron - '92 Mini Mini
90 day: 45.5 mpg (US)

Prius - '09 Toyota PRIUS Lounge
90 day: 47.37 mpg (US)

Beemer - '06 BMW F800 ST
90 day: 53.06 mpg (US)
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Actually, it is 14% improvement at an unknown lift.

Weird thing to start with on this head is it has a 2 angle valve cut instead of 3 (and that is stated by Suzuki)
15 and 45 but the seat goes from 45 with a big radius that reduces very much the diameter of the port.
I red somewhere that it is not detrimental to flow to have sharp edges up to 15 rather than curves and it gives you more surface for the flow.

Then the exhaust port is very much shrouded and apparently not aero friendly because the long side radius (where most of the flow usually takes places) is inverted towards valve guide (and obviously valve stem too).

Feet forward on this bike would require major surgery to the frame and France (where I live) is really not DIY friendly.
I will convert the seat to barely acceptable foam thickness one of these days but first things first : refurbishing of the head needs to be completed.
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