Tire mounting Q's

 OK, I *think* I want to try my hand at mounting my own tires. After doing a
bit of digging, I've come up with what I think are the tools I'll need to do
the job.

This: http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber4542
Plus this:
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumberB927

Along with this:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber ˜488

Plus stuff like valve stems, tire lube, and wheel weights.


Is there anything I'm missing, or anything that might be a better solution?
I know there's better quality stuff for the job, but I'm not going to go
into business with this stuff. I'm only going to mount a few tires a year.
I'm hoping to save a few headaches by asking around before I jump into it.

 armpit wrote:

I have the HF tire changer.  Works fine.  Bolted mine to the garage
floor with threaded concrete anchors, other folks have bolted theirs
to a sheet of plywood.  I've never unbolted mine since half my garage
is filled with bikes and bike stuff year round anyway.

I wouldn't waste the money on their tire balancer, I built one from
PVC pipe and a couple of pieces of flat galvanized steel for about
$10 to $15, based on an article in the March 2004 issue of
Motorcycle Consumer News (a bargain at $41/year):

http://www.visi.com/~olsonm/low_qual_tire_balancer_mcn_march_2004.jpg

I did not like the tire bar that came with the HF machine.  I ended
up buying a Coats combo tire bar with removable plastic tips, a far
better quality tool that doesn't scratch your rims.  But it cost 50%
more than what I paid for the tire changer base + motorcycle
attachment (I got them both together on sale for about $75, the Coats
bar was about $125 including shipping from http://www.tooldiscounter.com/ )
I do my own tires plus a couple of friends.  I've actually used my
tire machine to remove and remount a car tire too, imagine that!

 
The design of the tire balancer is genius (to bypass bearing friction
altogether).

Just two things about the article struck me ...

#1:  There should be a simple formula for calculating the approximate needed
weight from the time required to return to the natural resting position
from, say, 90 degrees off.  I can't see any disadvantage to iterating, but
one should be able to get a real good guess at the weight as a function of
wheel mass, diameter, and time to return to the resting position.

#2:  It isn't clear that one would really need to add more than one weight,
ever, if it is done carefully.  The reference to 3 weights and moving them
outward is a bit of a mystery.  Definitely I haven't ever done it and maybe
I haven't thought about the problem enough.

Real good stuff, and interesting reading.

The Lizard

 Jujitsu Lizard wrote:

As with many things, real world experience trumps theory almost
every time.  Most of the time, the axle does not move and the
bearings spin freely, giving you very precise balancing.  When
I find the axle moving it usually calls into question the state
of the bearings.  This obviously does not apply when the bearing
seals are tight on the axle but they usually bear on bushings
which aren't present so it's just the bearing and its lube
responsible for any friction.

All that BS about moving combinations of weights around goes out
the window when you do it a few times for real.  Once you try it
you quickly figure out that it is quite easy and balancing a
wheel can be done in a couple of minutes.  If you're bored and
want to get it "perfect" you can spend more time, it's hypnotic
watching the wheel oscillate back and forth for literally
minutes before friction eats up the stored energy.  In practice I
have found that +/- 1/8 oz is not significant, which is half a
wheel weight (7g or 1/4 oz).  I can usually detect the presence
or absence of a piece of duct tape a few inches long, which I
sometimes use to temporarily hold a candidate wheel weight on
while balancing.

 
Just cause I know nothing about this stuff, I looked at commercial
balancers, i.e.



I trust the mechanical design of the PVC one more than the ones with
bearings (for obvious reasons).  Of course, the ones with bearings don't
need to be leveled.

An obvious enhancement would be one with magnetic bearings, but I think
you'd need to be careful there because you could set up a situation that is
the analog of the PVC one not leveled.

Once I perfect my anti-gravity machine, I'll be entering this market.
Unfortunately, that is on hold while I work the bugs out of my perpetual
motion machine.

The Lizard.