New bike commuter looking for aero mods
 

Hey everyone, long time lurker, but I have made a few post before haha. But now im commuting on a bicycle, and using it for a hobby. Its a scott MT bike, typical diamod frame with front suspesion. My commute is about 5/6 kilometers a day to and from work. I've already put smoother tires on, and tried truing the wheels the best I could haha. I want to start playing around with aero mods on my bicycle. I already have a few ideas in mind. I had an idea of filling in the area between middle bar (where the seat post goes into) all the way to the drops outs on each side, ill give it a test run with cardboard if any body here thinks this is a good idea?

Im welcome to all ideas! and im all for DIY!

There are a number of things to try. A rear wheel cover then filling the volume between the seat tube and the rear wheel. A tapered tail box behind the rider and a front windscreen is great.

One quick and easy mod for a mountain bike is to put the end bar grips in close to the stem. I have mine 11 inches apart and I get the effect of one mph increase in cruising speed.

It's like aero modding a Jeep Cherokee. If you're looking for more speed, my advice is to instead invest in a used 10 speed. If you're looking for more aero, look at recumbents.

Things that will help you a bit on the mtb:

-get yourself properly fit to the bike
-narrower bars that let you reduce frontal area
-build a tubeless wheelset for lower RR. I'm running Surly Rabbit Holes on my single track bike but you might prefer something narrower depending on your tire size.
-a frame bag will help aero at low yaw angles and help you carry more stuff

At least do the bike fit and bars, then mess around with aero, taking hints from the aforementioned link.

Ok ill get to reading the links, and see what I can do about my frontal aera. Yeah haha its like aero modding a jeep ;P

There are useful posts in Aerodynamics and Motorcycle/Scooter sections. The body's widest part is at the shoulders, about 20 inches. Handlebar width is normally 23 inches. Any thing to deflect air around the chest and lowering your shoulder height helps but the biggest gain is from smoothing the air behind the rider as per the Rocket by Oscar Egg. At recumbents.com in Technical/bike building there is a thread on software for designing shells.

Thanks for this. I plan to shave my handlebars. I also lowered the stem a little over an inch to lower my shoulders. Comments on this and other threads helped. I can't afford a Zzipper fairing right now. The budget on this project has been expended.

Aeromods on a suspension mountain bike would be a waste of energy. You can make your bike faster with the tires like you did and by losing the front suspension fork.

Truly if you want to go faster, get you a road bike. You don't need an expensive carbon fiber bike, but a road bike with drop bars, 27" or 700c wheels, and the lighter weight will allow you more speed and more aero naturally. THEN you might consider aeromods.

This is my commuter bike. I like the upright position for visibilly in traffic. I did a 700c wheel conversion and road bike brake conversion on it since it was a 26er mountain bike. Average speed according to my computer is 12 mph on my 10 mile commute.........

http://i1272.photobucket.com/albums/...psjphmfrfi.jpg

This is my road bike. I also commute with it on days I do not need to pack a lunch. Nothing fancy or expensive but the average speed on this bike is 15 mph.........

http://i1272.photobucket.com/albums/...psvktcqasm.jpg

The difference in a road bike is the shoulder height and the shape of the fork. Homemade aero bars work on flat bars too. The large diameter tubes on the suspension fork can be shaped using strips of foam insulation. If a mountain bike is what you have to work with or prefer, then use it for now. All bikes benefit from streamlining.

Johnny Mullet's speeds match what I get on my commuter bike, Jamis Arragon 700c.

There is a software program available at The Recumbent & HPV Information Center to design aero shells. Included is the option for an upright bike and rider.

If you are in Florida or an area without hills you may not need more than one chain ring so that would eliminate the front derailleur. The 40T/28T low may be adequate for stop and go commuting.