bmc5733946 

I have a new set of Pasela tires I'm mounting that I cannot get the bead to seat. I have tried Ru-Glyde, silicone spray, dishwashing liquid (Dawn), extreme pressure 110psi, Park tire seating tool etc. They are labeled with the correct size 27x1 1/4 and went on without issue by hand, no tire iron etc. I have searched and found no real answer. What am I missing??

Brian

ThermionicScott 

If the tires are wobbly from not mounting straight, try letting out enough air so you can press in on the sidewalls with your thumbs to move the sidewall in a low spot up, or vice versa.

Polaris OBark

Put an inner tube in. Inflate it to the normal pressure, and let it sit for a day or so. Then deflate, break the seal on one side, extract the tube, put in the valve, and re-inflate.

(I have to do this with Rene Herse tires, which are made by Panaracer.)

soyabean

If the rim strip is rubber, that can keep a bead sticking to it. Make sure you have real rim tape like Velox.

jadmt

based on the bikes he has listed and tire size probably already is using a tube

ljsense

27" wheel so I'm assuming that you are using an inner tube. Are the rims alloy with hooked clincher beads? Or steel? Some 27" rims are hookless. Steel and hookless rims tend to be more of a pain getting a tire on right.

I'd take the tire completely off and start over. Check out the rim tape -- make sure it's flat and smooth. remount the tire and tube. Make sure the tube isn't pinched anywhere. Run some soapy water around both sides of the tire bead and rim. Then inflate to 110 psi. If it's not popping into shape, there's a tool that looks like a bratwurst gripper. You can use that or your hands to pull up on a low side.

Wear hearing protection in case you blow it off the rim.

FBinNY 

You failed to give specific details.

Are they too tight and seating low in places, or loose and sitting high?

Is the rim a hook edge without a center well, or one with a well and shoulders for the tire to sit on?

The answers will help get you the help you need.

bmc5733946 

So maybe some more information.The rims are new. Rim tape is Velox. The rims are CR18s and I have dismounted and remounted the tires several times, left overnight at 110psi, left for days at 110psi, used the Park tool. I have used every lube I have in my arsenal, Ru-Glyde, silicone, Dawn dish soap. The tire is low on the rim, and it seems to have trouble coming up on the bead in the area where the valve is, and for about 8-9 inches, it is happening on both sides of the tire and both wheels and tires. I even tried pinching the tire in the vise and moving the wheel back and forth as shown in a utube video. A little history about me, I worked as an auto mechanic for over 40yrs and have mounted thousands of auto and truck tires both tube and tubeless. I have experienced a tire explosion with an automotive tire at less than 45psi, not looking for a repeat of the experience. I have probably mounted more than 100 bicycle tires over the years. I have Paselas on other rims but not CR18s. They have been tight but not like this. I am throughly stumped by this situation. Thanks fellas for the help, I'll let you know what finally works, ain't giving up yet.

Brian

FBinNY 

As an auto mechanic you should know that tire seating is about finesse rather than brute force.

The particular rim has slightly raised shoulders with a minimal center well.

While you say "up" near the valve, I'm still not sure your tire is low and won't come up, which is very unlikely on rims of this design.

In any case, back to some finesse. You're dealing with 2 circles which must be concentric to work. If a tire is high or low someplace, then it's the opposite someplace else, or generally. You need to work the tire to or from the problem area to get the circles concentric.

Since the problem is at the valve, understand the the valve itself may be part of the problem, especially the wider base where it meets the tube. Address this by pushing the valve up into the tire to get the base out of your way, and allowing maximum flex so the tire can fine home.

bmc5733946 

FB, I do know that hence seeking help here after being stumped for several days. Thanks for the reminder.

Brian

FBinNY 

You replied while I was pausing. I hope you went back and read the whole post since.

maddog34

27 x 1 1/4"?... or 27 x 1.25"?...YES, there IS a difference... One (fractional) is for a Schwinn type rim, and one(decimal) is for a JIS standard, modern rim.

just checking... i just ran across this mistake last week.... not sure if Panaracer makes a Schwinn FRACTIONAL tire or not...

a trick i use with Continental Tires and other tight fits is to partially inflate the tire to about 10-15 psi, then work my way around the tire Twisting it, side to side... this helps the bead to get onto the seat, and also gives the tube a chance to get Un-pinched, if it was pinched... i had one Maxxis Ardent recently that refused to seat until i'd done the partially inflate/twist/ Finish inflating thing four times... with Dawn and water.... the other Ardent went on first try, no issues.

bmc5733946 

I'm not sure that the images are good enough to see.

I don't know if the image is clear enough but it is almost on but lacking just a bit. This is the one that is closest to being seated.

Brian

smd4

Sure looks good to me…

soyabean

Ultimately it's the grippyness of a bead to the rim, increased by how well a bead hugs a rim.

Some tyres don't like some rims. Some rims don't like some tyres.

Change to another kind of tyre and it's fine. Try the same tyre on another different rim and it's fine.

Polaris OBark

Yeah, I don't see where the problem might be. Did I miss something (apart from tubes vs. tubeless)?

smd4

You’re not using the tire label as any sort of guide, are you??

jadmt

I see what he is talking about. probably wants it to look like this.

soyabean

Right.

It's that molded line we're supposed to see uniformly on a good bead sit.

Like I said, I've installed every tire that existed, and you do run into allergic reactions with certain rims/tyres.

Polaris OBark

Sometimes it helps to deflate and re-inflate the tires. Sometimes these things will straighten themselves out when you ride them. Sometimes they will spontaneously regularize overnight in the garage. Usually they don't pop off the rim.