wheel aero,s?

[dave115mpg]

hi, to all, anybody had experience with wheel shields, ie, 2x disc,s making shallow cones to cover each hub and rim. grommet to access air valve, alloy sheets rivetted at the 2x edges, the top edge facing away from direction of airflow.
many thanks for any replies.
ps still working, on a modified constant velocity su carb for my motorcycle, have managed to source spare su carb, so will machine up reduced bore inlet venturi, and make a 3 to 4" long velocity trumpet at 12degree flow, plus put in a rolled leading edge, on the ram pipe , to reduce brakeup of laminer flow and increase gas speed, for torque and cfm. dave vizzard got a6% increase in cfm using these measurements hopefully i can hit 85mpg regular, at 55/60mph the mpg goes into 3figures mpg!!!,but air drag has a major effect, as i have marks on the throttle.

[fearlessjoe]

its done alot of road race pedal bikes..... on the back wheel.... but as i understand it its too dangerous to do it on the front because of the effect it has on the steering....

not sure if its because of side wind or just from the air hitting the wheel when its no longer straight.... but i definately remember it being a bad idea on the front...

on the back however.... i dont see why not, as long as you breaks dont get too hot... but if your doing this you probably dont use them much... might get dirty inside if you have a chain oiler.... but i dont see that being a problem......

in answer to your question... no ive never used them..... just my 2 pence

[dave115mpg]

hi, yes aero wheels on bicycles, i have seen at manchester velodrome, was going to only enclose the hub centre to outer rim, each side,
the rear disc andsprocket outside of the alloy shallow cones, wheelshields.
have just found a comment by hayes, re diesel bike, about low revs and maximising torque to vehicle requirements, thats why my 850 norton gets magic mpg at 2 to 2,500rpm!!!
also at 30mph the enfield streamlining gave 45% improvement on mpg, low revs small carb, and good torque from 350cc engine.
thanks for reply lots to think about.will make cardboard profiles when i remove each wheel, record all sizes, and acquire some alloy sheet.
best wishes for 2016

[Grant-53]

The issue with front disc wheels is in the side winds pushing the area ahead of the steering axis. Bicycles use flat spokes and aero rims on the front. See recombents.com and craigvetter.com for the latest design and construction of 2 wheel streamline vehicles.

[veloman]

You could also use coroplast (political signs) as a wheel cover. I think I may try it on my rear wheel. But I imagine I won't notice much of a difference. It's something that will help, but on it's own, hard to tell.

The idea behind it is that the spokes at the top of the wheel as passing through air at twice the speed of the bike. Put the rear of the bike on a stand and feel the air movement next to the wheel at full speed. It's something. Maybe 50watts, maybe 200w.