After spending a very frustrating week trying to mount my tubeless  tires on the Matco rims provided I  have given up. The O-rings they supply for sealing the two halves of the rims together absolutely will not fit. Matco say to roll the O-ring over the rim to the flat at the edge of the rim, assemble  the two halves and roll the O-ring back  to the center of the rim and lubricate the O-ring  and you should be good to go. Well this is absolute impossible. the O-rings are to small  and do not have enough stretch to fit over the rim as the instruction state no mater how hard you try  "my fingers still hurt" from tying to stretch the O-rings over the rims this week". Matco has been no help whatsoever, they just tell me to read the instruction.

So is there some secrete to assembling these rims??

Any help or suggestions would greatly

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Comment by Richard Benson on August 30, 2019 at 5:20pm

For added help in holding the rim while stretching the o-ring over it: I took a scrap 5/16 bolt and inserted it through one of the bolt holes then sit the rim down on my big vise and tighten the vise jaws onto the bolt. The wheel half is now held firmly down and you can pull on it all you need to. Works great every time !

Comment by Paul Sanders on August 26, 2019 at 8:19pm
I got so frustrated trying to do mine I invented new curse words while trying. Then one day I went back to the hangar (largely with the idea to burn the whole thing down) and they went on easily. The instructions really do work!
Comment by Phil Smith on August 25, 2019 at 7:20pm

Ok quit  tearing your hair out, breathe this is easy.

Because you haven't done these rims before get out all the necessary hardware and practice assemble dry so you have the right wrenches - hex,  standard and sockets with proper extension all ready.

Take the wheel half without the valve stem and put it inside down on your bench on a piece of padding. 

I know it sounds crazy;  but lube and stretch the o'ring over the rim flange onto the flat spot just under the rim flange.  Use the bench for support and work it over the rim flange.

Next coat the joint surfaces between the rim halves and into the radius with some sealer - I use fuelcheck.

Carefully now put the tire in between the rim halves; start with the rim half with the valve stem. Be careful here not to disturb the o'ring.  Now carefully bolt and torque the rim halves together.  

Now and only now roll the o'ring off the flat and it will snap into place.

Some tires will seal and inflate - I just did a 21 800X600 tundra that  wouldn't seal so had the put a tie down strap around the od and squish it into place.

I can't roll the o'ring from the inside up and over the flat a'la MATCO but have luck with doing it this way.  Last six tires I did are still up and that's been years ago.

Still grinnin!

Phil Smith

CH 70wonderful

Buhl, ID

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