How to mount an impossible tyre
 

Mounting a tyre to my new wheel build, both 27.5, but the tyre is stupidly stiff, nothing on YouTube has worked and it almost feels as if its too small for the rim it's so tight. Anyone got experience with tyres that feel so impossible? Best way to either mount it or loosen up the tyre?

Many of us I'm sure have been in this position.

Leave them in the sun for a few hours.

If no sun......use a heat lamp ( that's what I use) or a hair dryer.

They also make a tool to help pull the tire on.

It's about 15.00


I'm not sure what they call it. But can Google it to find out.

I have spent nearly an hour on ONE tire before....


The heating and tool help immensely.


Good luck and be patient

You have to get and keep the bead of the side you are putting on the rim off of the beadseat and in the spoke channel. The side that is already on needs to be pushed out of the spoke channel. Otherwise there won't be room for it, the tube and the side you are trying to put on.

Some new tires you might have to leave alone after you've gotten them as far as you can go with them. So go have a pint or cup'a. When finished, see if you can get a few more millimeters over the rim. Then go while away your time with something else again. Then rinse and repeat.

Though it's been a long time since I've ever had issues. Since realizing that I needed to push the bead seat of the side that is already on the rim completely out of the spoke channel and onto it's bead seat, then I've had few issues with tires.

Now if you can't get the first side of the tire on the rim, then are you really certain both are 27.5 tires. What's the ISO size say? Hopefully both are something x 584. And hopefully the rim is 584 BSD too.

Not sure what you've tried already.

- The first thing to do is to get one side fully mounted, with the bead in the center of the rim, where there's a little trough that gives you some slack. Get the other bead mounted as much as you can, also pressed into the trough.
- A tire jack is super useful with tight beads.
- Soapy water can act as a lubricant to help slip the last bit of bead over the lip of the rim.

First off this assumes that you have the bead pushed into the middle of the rim. That point is the smallest rim diameter and gives you the most slack.

When you get to the last 7-8 inches to get on the rim, you can't go at it in the middle. It's just too tight.
So you have to start at one end. Problem is, as fast as you lever one end on to the rim, the other end slips off and moves around the rim.

Take some parachute cord and bind the left side of the last 8 inches to the rim. This will stop it running away around the rim.
Then lever the right side of the last 8 inches onto the rim.

My 5000's are so tight, I carry parachute cord in my saddle bag for this purpose.

Barry

...FWIW, there is a way to use the fact that the valve stem locks the beads in place, when you have that portion of the tyre mounted, to do this same thing. Try it, and it will probably work for you, Doesn't work on wide rims, but it works fine on most road rims. If you need to push the valve stem of the tube up, to allow the beads to fully seat, it will work. In case you find yourself without any cord some day.

The tightness of the bead & ensuring it makes it to the center of the well has already been mentioned several times.

On occasion, the stiffness of the sidewalls of the tire can be so stiff so as to be the problem. I've had this happen mainly on heavy duty tires that were very deformed & smashed flat during shipping where the ridiculously thick sidewalls sat compressed under many other tires for months on end until a customer bought it. The fortunate thing is that once mounted & inflated the tire takes "a set" to be round & consistant properly from there on out.

In any case, have a seat, get the first bead on. Then work the second bead around until you can't go any more. Then lock your progress with one tire lever & hold it with your knee. Hold the other end of the bead firmly against the rim with your thumb & use the second tire lever spoon side to the rim to lever the bead over the rim. Just be careful not to pinch the tube. This may take several attempts & re-trys of pinching & draging the tire to get the second bead well set in the well while levering the second lever. Finishing at the valve stem ensures the valve stem doesn't take precious mm's of needed space.

I find Pedros levers are the best & the profile at the spoon end tends to avoid pinching the tube better than other brands I have dealt with.

It is 100% technique...& strong thumbs. You'll get it. :thumb:

Whatever tools you need to mount the tire will need to be taken along in case you get a flat on the road, or you will be stuck.

What rims, tires, and rim tape are you using? :)

whatever you do, don't use a bench vise & locking vise grips eek!

I assume you've tried using tire levers to work it on? Maybe using some KY to lubricate? And as others have mentioned you've got the first bead in the deepest part of the rim?

How would you rate your grip strength? I read numerous complaints about how Schwalbe Marathon Plus tires were supposedly all but impossible to mount, I don't know if Schwalbe changed something about how they're made because of complaints by the time I got mine but I didn't have a problem with them.

Are you sure your rims are for 27.5" and not 27". 27.5" have a 584mm diameter while 27" are 630mm. Both are measured at the rim bead surface not the rim sidewall. Perfectly normal in the bike industry. :foo:

A shop tool is great, but consider how you're going to deal with that if you get a flat on the road somewhere.

I've been using a set of VAR tire levers, with a bead jack, for 40 years. I've rarely needed to use the jack function, but it always works when I do.

They still make them, but they're blue now. Rarely seen for sale in the US (occasionally on eBay), so you'll have to look to one of the UK online bike shops. like SJS.

https://cimg2.ibsrv.net/gimg/bikefor...2fcd087921.jpg

https://cimg0.ibsrv.net/gimg/bikefor...4fd88f6a3c.jpg

That's what made all the difference for me the once time I had an "impossibly" tight fit. Paint it on the rim and inside the tire at the place where it gets stuck. Good luck; I feel your pain. Also, wear gloves with tacky surface to maximize your grip on the tire.

Curious if you have found success and which advise worked best for you?

I myself had used many of the above advise on getting both my son's and my Conti tires on our tubeless wheels when converting to a tubeless setup. They were a pain! But was easier after making sure they were warmed up in the sun, made sure first bead was in the center of wheel well, and used the Pedro levers to finish off getting the tires on. Then soapy water to properly seat them without any further issues.

My sons bike was especially difficult, since the tires were originally on 20mm interior diam wheels with tubes. Putting them on a 25mm diam wheel as tubeless was not at all easy and why I put these in the sun to get them to be easier to handle.

Shimano RS700 wheels with Continental 5000 TL 700X25.
Wheetset and tires were new.
I mounted one tire on the rear wheel with a struggle, but in one effort.
I tried mounting the other tire on the front wheel, but after struggling hard, wearing light work gloves to increase the grip, I gave up after struggling for 15 min and with bruises on my palms.
Tire lip in the rim well, and pulling all the slack as much as possible.
I decided to leave the half mounted tire in the sun for about 3 hrs (26 Deg C).
Then I tried to remount the tire which I did successfully with a struggle, but one hard try. There was definitely a difference.
I suspect there was a slight difference in tire diameter, and rims have a different profile.
However, heat made quite a difference.