The largest wheels I know are these (I measured 110x63 mm, including tyres), but they are quite rare (only available in one single set):
Weels: 22969 "Wheel Technic Racing"
Tyres: 32298 "Tyre Power Puller"
The wheels itself are not that big, but if you include the tyres, they are really huge:
They would probably work really well for an RC car.
I think the smallest one in diameter is the tire 3641
with the bush 4265c.
Alternatively, you can use the tire 3139
which has a smooth surface and also compatible (but a little bit loosely) with the same bush.
With a bit of trigonometry and some observation we can estimate a theoretical limit to the maximum length.
I assume you are looking for the maximum length that would run on the sharpest possible curve, which appears to be one made with flexible track. By observing this photo of 52 flex track pieces arranged in a circle, we can estimate that each piece can ...
You can always brick-build a wheel. The curved slope pieces can closely approximate a circle.
For example, 12 4x1 curved slopes gives a circle with a radius of 160 LDUs (8 studs).
For more information on brick-built wheels, I suggest you refer to the "Brick Built LEGO Wheels Book":
I can't speak to "best". But as a point of reference, many many of my lego tires are many years old and they are usually stored on rims. The older tires were often not removable from the rims. As I rarely build cars, I take no special care of the tires, and I've found that there doesn't seem to be any particular problems. The rubber ages over time, but this ...
The main trick is to simultaneously push all three pins of the hub:
If you have another hub, and the wheel allows for this, take it and push carefully from the other side. If both hubs are half-way in, you should be able to pull out both.
Otherwise, take two wedge belt wheels, align them on top of each other, insert a pin into every second hole and repeat ...
This seems pretty much bordering on the impossible, given the current state of (LEGO) engineering capabilities. What you are describing is a Von Neumann Machine and as far as I know nobody succeeded in creating one, not just in LEGO but in general.
The problems you'd have to overcome:
The robot must be capable to exert sufficient force to overcome the ...
An alternative is the 94.8x44 balloon tires. While they are not as big as the ones elusive suggested, I imagine they are easier to get as they have been in some recent sets.
Middle: 94.8x44 balloon
Right: 81.6x38 balloon
I went to Brickcon 2012. I asked Joe Meno about his red Monorail and he was most helpful. He flipped it over to expose the undercarridge and he was able to show me LEGO tires with fifteen hours of running time. The tread does indeed wear off and the tires actualy begin to split. The rubber doesn't cling to the rails themselves, but residue does begin to ...
Likely you'll have the differential gears oriented wrong in the front or back section.
The differential gear is this piece:
Please check the instructions carefully and see if the orientation of this piece in the instruction book matches your build.
Here's what found after playing with all kinds of combinations. With this the three rovers will be at the same scale (about 1:5.8). This scale is small enough that the big rover (MSL) would not be a monster to build.
The ratio is almost spot on and the only main problem is that the MSL wheels (the big ones) will have those big cleats.
On the positive ...
LEGO and others sometimes calls those pieces a "bearing element". This term however is not limited to just that axle.
LEGO's replacement parts service calls the holes they go into "HOLE Ø11" (possibly read "Hole Diameter 11"):
The width of the axle is roughly equivalent to the width of a "bar", like the 30374 piece used for Lightsabers as such.
None of ...
What you have there is a 6118 Wheel Hard Plastic Small (22mm D. x 24mm), and this wheel is pretty common, it features in 39 sets, but luckily for you only in 4 sets in the color White. These sets are:
1704-1 Ice Planet Satellite Plow - this set has 6 of these wheels.
6983-1 Ice Station Odyssey - this set has 10 of these wheels.
6814-1 Ice Tunnelator - ...
It looks like LEGO sells chain and sprockets, don't know if you'd have them lying around though.
You could also try using pulleys instead. If you don't have any of the actual pulleys, take the tread off of two wheels and stretch a rubber band across, that should work too.
It would probably be easiest to work out the which piece should be used for the biggest wheel.
The largest wheel I could find came in the 8420 Technic model. Two of which can be used in tandem to increase the surface area of the wheel:
Wheel Technic Street Bike (8420)
The medium wheel could be a rather blocky Wheel 20 x 30 Technic, the 68.8 x 24 or the ...
There is also the Technic Gear Mobile Devastator Wheel, but it's not really suited if you want a realistic car. If you want to build a funny-looking vehicle, however... You could even build a complete vehicle which fits completely inside the radius of two such wheels, so that it can turn on itself when you reverse the polarity. Again, not a car, but super ...
The Technic Riding Cycle theme features several bikes that may be of inspiration. One particular set Moto Cross Bike (42007) uses several 3711: Technic, Link Chain parts to make a chain.
Based on Bricklink prices for the last six months, 39 chain pieces (the amount shown in the set above) would cost £4.29 (Aprox. $6.91 or €1.26).
Pulleys and rubber bands ...
Should they be stored with or without rims inside?
I cannot say for sure whether storing tyres with or without the rims connected affects the lifespan. In my experience it hasn't made any noticeable difference.
There are four practical reasons I can think of not to remove the tyres.
It can take a lot of effort to remove tyres and put them back on again, ...
Hey, there Happy Dog! These train pieces?
Part #BB37 - Train Brick 2 x 4 x 1 1/3 Sliding Block with Wheels
Part #Wheel2A - Wheel Spoked for Motor.
Together they appear in these LEGO sets.
I really expected someone with chemistry leanings to explain to us what was "migrating" out of the rubber with time or temperature, to make them "greasy"...much like cocoa butter will migrate outside of M&M's that have gotten too hot in their package.
The question "chicks" linked to gives some good answers though, and it's encouraging that no one has ...
I was able to find a few elements that are able to make this connection possible. I'm guessing the designer used some type of bar-sized element which is made from a different material that is able to compress slightly more than regular ABS. For example, the softer plastic used on some minifig weapons seems to work nicely:
Another option could be flexible ...
The math you're suggesting may work for going straight forward or backward where slipping is limited. For a turn, it will not come close. Even getting the center of rotation of the turning robot will be difficult. The tracks will have to slip. A tracked robot can not turn without those tracks slipping. Differences in friction will alter the turn. More ...