Bicycle Mechanics - ADVICE NEEDED - use 27x1-1/8 tires on 27x1-1/4 rims?

I misordered some panaracer pansela tires yesterday online to replace some old tires on my dad's Romic bicycle that he had bought 30 years ago.

The bike shop has already sent them out.

When I called the shop, I was told that the 27x1-1/8 tires might fit on the rims that I already have.

Does anybody have any suggestions?
Will the 27x1-1/8 tires fit though my rims currently are holding 27x1-1/4 tires?

Keep in mind that I've read that the bead on today's tires doesn't fit well with old rims (even when they are of the appropriate size).

if they do fit it be a very tight fit. you be better at matching the ISO number on the old tires and/or rims. try returning them for the right size.

Try them on before you send them back.
Personally, unless they are not the size the sidewall says they are, I can't see any problem.

The size difference will be no problem. My '85 Bridgestone 400 came factory stock with 27x1-1/8" tires on rims marked 27x1-1/4".

However there may be another problem. Really old rims lack a "hook bead", that is a ridge inside the rim's tire channel that mates with a corresponding groove on the tire bead. The hook bead along with matching tires forms a strong interlocking grip and allows the tires to remain on the rim at high pressure of 100 psi or more. Older "straight wall" rims lack this bead and won't retain even snug fitting tires above about 80 psi.

My '85 Bridgestone came with hook bead rims but a friend's Raleigh from the early 70's did not so, sometime in that interval, hooked beads became the norm.

They should work safely. I wouldnt run them at the max recommend pressure though.

Weinmann concave is an example of a wire on rim without a hook bead..
inside surface is concave giving the rim sides a wide brake track.
what rim exactly is on the bike ? brand name.

you Know Pictures if you cannot read a label... and measure how wide the rim is ..
Hook bead + 19mm wide and you're good .. if its a wide ... touring rim may still be Ok,

Once you got the old tire off see if there is a crochet inside.. :50:

Thanks.
I appreciate your advice.
Though the bike shop will exchange them, I was hoping that they would fit so I wouldn't have to pay to have them shipped back and have the new ones shipped again.



if they do fit it be a very tight fit. you be better at matching the ISO number on the old tires and/or rims. try returning them for the right size.

Thanks for your input, everyone.
I appreciate it since I know nothing about bikes.

The rims are labeled "ARAYA 27x1-1/4 w/o HP. JAPAN" and they say Shimano on the hub/axle(?).
I'm not sure if I'll be able to measure them; I'm a poor college student without a tape measure.

They are certainly straight-sided rims with no hooked edge.

if the rims had a hooked edge, then from what you all have told me, it seems that i would be able to use them.
however, no one has confirmed that these smaller width tires have worked on any straight-sided rims.

input?

You can use those tires. They wil be fine as long as you use care when inflating. I run those tires on the same rims and inflate to 90lbs. with no problem. I wouldn't go over 90lbs.

Any 27" tires can be mounted on any 27" rims.

The difference will be in the width of the tire - 1-1/4 is slightly wider than 1-1/8, therefore it has a larger volume of air and provides more cushion to the rim, bike, and rider.

The main drawback is the need to run slightly higher pressure to avoid pinch flats.

LDSF

You will be fine, Ive used 27 X 1/14 and 27 1X 1/18 on my wheels marked 27 X 1 1/4. psi for the 1/4 was 90 and the psi for the 1/8 was 105 and im yet to have a problem with either of them. Same Araya rims also, no hooked side wall or anything, and I commute 250 miles a week. So you will be fine. good luck.

Going in the other direction, I have a 1983 Fuji Touring Series IV, with the stock black/grey UKAI 27x 1 1/8" rims. The stock tires are 27x 1 1/8". The rims are notably narrower than our other bicycles, which use 27x 1 1/14" tires. I am considering the use of wider, 27x 1 1/4" tires. Will this work?

The rims are labeled "ARAYA 27x1-1/4 w/o HP. JAPAN" and they say Shimano on the hub/axle(?).


The vast majority of entry to mid-level Lotus bikes came with 27x1-1/4 rims and 27x1-1/8 tires installed.

Going in the other direction, I have a 1983 Fuji Touring Series IV, with the stock black/grey UKAI 27x 1 1/8" rims. The stock tires are 27x 1 1/8". The rims are notably narrower than our other bicycles, which use 27x 1 1/14" tires. I am considering the use of wider, 27x 1 1/4" tires. Will this work?

If they will clear the stays and bridges, etc., they will work fine.

I go up and down with regard to tire sizes all the time on new
(old used but new to me) bikes, and have yet to encounter a problem
that could not be solved bu adjusting pressure/tire width with
this one exception, i.e. if the tire is too wide to run through the
bike frame and brakes as configured.

It's true that certain width rims will hold a better tire profile and
contact patch for tires that are ideally matched for them regarding
width, but practically speaking, if your tire's bead is the correct
diameter for your rim's bead diameter, they'll usually work.

The difference between 27 x 1 1/8 and 27 x 1 1/4 is pretty insignificant,
and in fact all tires so labeled are not necessarily accurate in designation.

I used those tires on 27x1-1/4 rims and they were fine.

Thank you 3alarmer.

In the old days, this was a non-issue and you could use any tyre with straight-side rims. That's because ALL tyres had steel beads like the Panaracer Pasela. The steel bead doesn't stretch and will retain its diameter up to about twice the rated maximum-pressure on a straight-side rim. Then in the '80s, along came kevlar-beaded tyres to save weight and allow folding convenience. These tyres DO stretch a little under pressure and must be paired with hook-edge rims in order to use them at maximum pressure.