Any Tire guys here? Trouble mounting a tire

[Gus_Mahn]

I have new tires for my '16 ATS-V, and I have a Coats 70XAH tire changer. My wheels have a steep outside step on them and it's keeping the new front tires 265/35/18 Brigestone RE71r's from beading all the way up. They hold air but there's a 6" portion on the outside where the tire won't bead all the way. The tires are 10mm wider than the OE 255/35/18. The + size is a common replacement, and I got the tires closeout for $114/ea, usually $300/ea! I've used the extra hand to push the tire off the bead a bunch of times and lube it, and I've put up to 60 psi of air into the tire. Thinking about putting it on the car and going for a ride. The rears are OE sized 275/35/18's. They were a bit of a pain but I got them mounted. I've done a lot of tires, but these are beating me. It's hot as heck, and I'm trying to Auto-X tomorrow. Thank you

 

[driftpin]

What about just putting the not-fully-beaded portion at the point of tire pavement contact, and then just turning the steering wheel? I think turning-away from the not-seated area would quickly 'pop' the bead against the wheel rim.

 

[Gus_Mahn]

I'll try it.

 

[Copymutt]

If I’m understanding the issue, the tire won’t expand to seat the bead. In Liu of a pneumatic restrictor I’ve used a ratchet strap around the center of the tread to force the sidewalks out to the bead. Of of course you know about starting fluid.

 

[theoldwizard1]

Others will tell you not to do this, but "back in the day" we would go up to 100 psi to get a bead to seat.

 

[Cheepbeer]

Others will tell you not to do this, but "back in the day" we would go up to 100 psi to get a bead to seat.

And if that wasn't enough...ether.

 

[39CAMC]

They hold air? How high are you running them before giving up? RE71 in certain sizes and on certain wheels is a known problem in performance circles, but the problem is getting them to take air in the first place.

If they are holding air and just not seating, lube the hell out of it and run the pressure up until it goes. It is not unusual to have to use 100+ psi on these.

DaveW

 

[Gus_Mahn]

Got it to pop by driving on it with 55 psi and jamming on the brakes. No joy just turning the steering wheel on the ground. I'm so f'n tired and hot I put the other front on in the wrong rotation. Cooling off then flipping it, going for a ride, and pulling it to balance, but I'll try 80 or 90 psi to fully bead it first. Since my wheels are on the small side for the width, they took air pretty quickly, and a lot of high quality lube was used. It's great having a tire changer, but somedays it's still just a lot of work!

 

[txvwnut]

Get you some of this or something like it. https://shop.myerstiresupply.com/ERP2Web49/e2wItemMain.aspx?parentId=00029568

 

[Gus_Mahn]

Done. Beaded up completely at 80 psi. There are youtube videos of people intentionally blowing up tires, and it takes a lot more than 100psi typically.

39 CAMC what do you run in CAMC? I'm thinking of tuning my car, and getting wider tires and running CAMC. I'm not fast, but I'm having a blast.

 

[seber]

What are you using for rubber lube?

 

[bobg03]

If I’m understanding the issue, the tire won’t expand to seat the bead. In Liu of a pneumatic restrictor I’ve used a ratchet strap around the center of the tread to force the sidewalks out to the bead. Of of course you know about starting fluid.

Ratchet strap installed when lire is first placed on rim...99% success rate

 

[APEowner]

I've had some success with putting in as much pressure as I'm comfortable with and setting the tire in direct sunlight.

 

[Copymutt]

Some brands such as M/T street radials state on the side wall “ Do not exceed stated pressure to seat”

 

[fsae0607]

In my tire shop days, we had to put about 120 psi in a set of 25 series tires to get the beads to seat! Make sure you're wearing ear protection, as it sounds like a gunshot when the bead seats

 

[metaleltr]

Some brands such as M/T street radials state on the side wall “ Do not exceed stated pressure to seat”

Most brands say that, some in finer print than others. Generally they list 30psi which is a industry safety limit. That being said modern low profile tires will rarely seat with less than 50psi.

When I worked at a tire shop in college the local Chevy dealer would bring Corvette tires to us that they couldn’t get to seat. We would put 100-120psi in them and set them out in the sun.

 

[39CAMC]

Some brands such as M/T street radials state on the side wall “ Do not exceed stated pressure to seat”

I don't want to be cavalier about this, especially since I had a brand new defective tire blow up on me a month ago (at about 40psi), but if one followed the warning on the sides of tires while mounting, they might still be finishing mounting their first set that they started 20 years ago. We/I almost exclusively mount performance and race tires and so few of them would *ever* seat at 40psi or even the 60 the machines (try to) limit us to. And yes, I know what I am doing and yes I use good lube.

DaveW

 

[Gus_Mahn]

What are you using for rubber lube?

It's very slippery