Gettin' Ready

Dec 23, 2011
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[/IMG]Two Street Pro's just about ready. Still playing around with wheel designs for the "Black Bird".

Ok, I still haven't figured out how to post pictures on here.
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VERY nice, one thing to remember, while i realy like the center wheel, the one with 1 spoke. It may unbalance things, even the small amount of weight on the one spoke will cause a unwanted vibration with all 4 being in different places while spinning it could be a disaster going down the track. stick with the balanced ones, they look great too.
 
Cars and wheels look great. If your going for looks, you got the wheel thing down. But if your looking for pure speed, your going to find that a full wheel (wheel without cut outs) will run faster than your current versions due to the air flow. I know it seems nuts but when you get those little wheels running down a track, the full wheel cuts through the air and the cut out wheels act like a fan and you have air going all sorts of directions and slows your car down. I did a lot of testing a few years ago with the Derby Worx RS-X wheel (RS wheel with about 100 holes in it
hmmm
/images/boards/smilies/wink.gif and even though it was lighter than the RS full wheel, the RS beat it in ever sort of test i did. I too have laser cut some designs in wheels but still know they will not out perform the solid wheels out there today. Again, this is just my opinion and i look forward to seeing anything you send. You look as though you are a veteran at building.

Ian
 
You may be right. I'm really just getting started. I have a lot of testing to do, but that's part of the fun. I admit I am more in to style more than I am at trying to build the fastest car, but I still want to be competitive. Trying to find a good balance. I was thinking a lighter wheel would take less energy to start rolling, thereby resulting in more speed down the ramp. I do have a way of balancing the one-spoke wheel. I mount it on a mandrel on my pencil grinder and shave off the thick side of the rim until it spins smooth at high rpm's. Once I get the first one balanced, I duplicate the same numbers on the mill for the next three. Thanks for your advise. I'm sure I will most likely get the same results as you did. But getting there through trial and error is where the fun is, atleast for me.

Dave
 
Goat_Boy said:
Cars and wheels look great. If your going for looks, you got the wheel thing down. But if your looking for pure speed, your going to find that a full wheel (wheel without cut outs) will run faster than your current versions due to the air flow. I know it seems nuts but when you get those little wheels running down a track, the full wheel cuts through the air and the cut out wheels act like a fan and you have air going all sorts of directions and slows your car down. I did a lot of testing a few years ago with the Derby Worx RS-X wheel (RS wheel with about 100 holes in it
hmmm
/images/boards/smilies/wink.gif and even though it was lighter than the RS full wheel, the RS beat it in ever sort of test i did. I too have laser cut some designs in wheels but still know they will not out perform the solid wheels out there today. Again, this is just my opinion and i look forward to seeing anything you send. You look as though you are a veteran at building.

Ian
Goatboy is right on.
Prior to the MOTM race, I took the car that eventually placed fourth in the MOD race, and placed DerbyWorx wheels with all the holes, and timed the car. I prepped the DerbyWorx wheels exactly the same as the solid disks, used the same body, axles, and drift, and the car was 2/100 slower. That's 3 inches. Had I run the car that way, it would've placed last.

A couple of months ago, I took a set of bearing wheels, and drilled four 3/8 inch holes, then balanced the wheels. Same results. I thought I could overcome the air problem by reworking the four holes so that the edges were razor-sharp. All I could pick up was 2/1000 of a second. Totally noncompetitive.