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Full Version: CSOB thwarted again, 3-piece rim tire mounting fail
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mskala
So, for my Fuchs centered BBS race wheels, 7.5x16, I finally have the need to put
on the Hoosier A7. (My tires last a long time since I don't do too many events per
year).

A while back, I got sick of tire places that charge $75 or more to mount up the stuff
that they don't sell. I told them if they would sell Hoosier I would buy it there.

So when I had the A6, I just took apart the wheels and assembled on the tires. Don't
need good balancing for low speeds at autocross so I can do that on a bubble.

The A7 in the same 205/45/16 size looks identical in dimensions, but the damn things
will not seat the last part of one of the beads. I'm not going above 40psi. I used a
rubber mallet for a while, I put one on the car to shake it, then I went up and down
the driveway a few times, then a few hundred yards down the street slowing going
side to side. No dice.

Now I have 2 like this and the other 2 I haven't tried at all. Any special way to make
this work or do I have to crawl back to the bastards with the machinery?

Thanks
bretth
Harbor Freight sells a manual tire changing stand for $45. Don't know how well it works though.

http://www.harborfreight.com/automotive-mo...nger-62317.html
mskala
QUOTE(bretth @ Aug 8 2016, 12:45 PM) *

Harbor Freight sells a manual tire changing stand for $45. Don't know how well it works though.


I don't have one of those, but they are only going to work with steel rims and
high-profile street tires.
mskala
Bead won't give in (holds air fine though) biggrin.gif

Click to view attachment
stownsen914
Silly question perhaps, but I assume you've lubed up the beads well with soap? (or some like hair spray if you have any issues with tires rotating on the rims while driving)
6freak
yep soap and water...and why not go over fourty psi to set the bead? might only take 42 psi to pop hahaha pun intended ..dont be scared biggrin.gif

MikeC
sixnotfour
always use lube...
mskala
Strangely, on the A6 I did not use any lube at all, with no problems.

Now, I made the mistake of reading a bunch of crap on the internet, so apparently
some soaps have a sodium hydroxide which is not good to leave in contact with
aluminum. So I went with K-Y. Seems slippery, but once part of the bead gets into
the right place, the last part has a bigger hump to get over. It's maybe only 1/8"
bigger diameter but won't budge.

The tires say right on the sidewall not to exceed 40psi when seating. Also, BBS of
course is a spun aluminum rim piece which I'm sure is not as strong as a 1-piece.
I don't want to damage anything.

Maybe I'll find a good soap and use tons of soap and water.
Randal
QUOTE(mskala @ Aug 9 2016, 08:20 AM) *

Strangely, on the A6 I did not use any lube at all, with no problems.

Now, I made the mistake of reading a bunch of crap on the internet, so apparently
some soaps have a sodium hydroxide which is not good to leave in contact with
aluminum. So I went with K-Y. Seems slippery, but once part of the bead gets into
the right place, the last part has a bigger hump to get over. It's maybe only 1/8"
bigger diameter but won't budge.

The tires say right on the sidewall not to exceed 40psi when seating. Also, BBS of
course is a spun aluminum rim piece which I'm sure is not as strong as a 1-piece.
I don't want to damage anything.

Maybe I'll find a good soap and use tons of soap and water.


Clean and polish(*) the inside of the barrrel before putting it together, then as others said, use soapy water on both the barrel and the rim.

(*) the smoother the aluminum barrel the better.

And if it doesn't seat at 40psi, take the tire back as outlined in the Hoosier race tire guide. From: http://www.tirerack.com/tires/tires.jsp?ti...mp;tireModel=A7

WARNING BEAD / RIM SEATING
When seating beads never exceed maximum bead seating pressure as molded in tire sidewall. Never exceed manufacturer’s maximum inflation pressure. Always seat beads with wheel locked to mounting machine or placed in a safety cage. A damaged tire or wheel can fail during bead eating and burst wit
h enough force sufficient to cause SERIOUS PERSONAL INJURY OR DEATH.
Always use a clip on chuck, an in-line valve with a pressure gauge or adjustable regulator and remote inflation/deflation device. Have enough air hose
to stay out of the trajectory. Stand back. If the beads will not seat at the manufacturers maximum bead seating pressure, STOP, deflate tire, return the tire to the place of purchase.
mskala
QUOTE(Randal @ Aug 9 2016, 03:28 PM) *


Clean and polish(*) the inside of the barrrel before putting it together, than as other said, use soapy water on both the barrel and the rim.

(*) the smoother the aluminum barrel the better.


Good idea, I never thought to do it.
6freak
10 4 on the over 40 i had no idea you learn something new evryday
smile.gif
mskala
Had time to try one tonight. I cleaned and polished to the degree possible,
then used a bunch of palmolive, and it popped on at 30psi.
6freak
QUOTE(mskala @ Aug 9 2016, 06:10 PM) *

Had time to try one tonight. I cleaned and polished to the degree possible,
then used a bunch of palmolive, and it popped on at 30psi.

piratenanner.gif driving.gif go use um up
mskala
All 4 are on. I think I figured out the basic problem. I'm using 6" inner
and 1.5" outer. The inner always popped right in, there is only a small hump and
it stays aligned during assembly. But the 1.5" outer doesn't have anything after
the hump, it takes a 90 degree turn there. So about 1/2 of it seats during assembly
and then the other half has a big hill to climb. I needed to clean that part with
scotchbrite really well, then smear on the dishwashing liquid to that piece and to the
bottom of the tire bead. Then by the time you get to about 30 - 35 psi it slips past.
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