Bicycle Mechanics - Max tire width on 27 inch rim???

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View Full Version : Max tire width on 27 inch rim???


CollectiveInk
10-10-08, 09:17 PM
Anyone know the max tire width for a 27 rim (on a motobecane nomade)? My son blew out the front tire on his bike today (Conti gatorskin 27x 1.25) so I need to replace it and the rear.

Since he is fairly new to roadbiking (coming from dept store bmx and a trek MTB) he is sometimes a bit shaky or tends to weave. I was wondering if a slightly wider tire might help some.

So is 1.25" the widest tire made for 27" wheels?

Thanks in advance for the help.


Panthers007
10-10-08, 09:31 PM
xx

CollectiveInk
10-10-08, 09:51 PM
I know there are 27 X 1-3/8th" tires available. Not sure about larger, or fit. But those should work fine for the rims on an old Motobecane Nomade. I had the model up from the Nomade back then. I believe the rims/wheels were the same as the Grand Touring. They were good wheels - bombproof in my experience.

Any idea where to get them? I can only find 1.25" so far. And the ones on 'bay seem dubious. Performance and Nashbar don't seem to have too many in stock. Any other good sites to try? BTW...our LBSes don't stock 27", or at least none less than $60 each.


JustChuck
10-10-08, 10:01 PM
1.25 or 1 1 /4" ?
There is a difference. And I have never seen a 27" tire with a decimal width. Ever.

CollectiveInk
10-10-08, 10:02 PM
Isn't 1.25" = to 1 1/4" ?

Panthers007
10-10-08, 10:13 PM
xx

JustChuck
10-10-08, 10:13 PM
NO
Go buy a 26x 1 3/8 tire(and there are two different sizes) and try to mount it to your 26" modern mtb wheel
27" is 630 bead seat. Modern wheels are 700c and have a 622 bead seat. The width is relevant, altho it matters little, other than making you look like you know what you are talking about, because there are no decimal width tires in 27" (Except, maybe tubulars, but that is another kettle to fry)

mikepoole
10-10-08, 10:18 PM
Isn't 1.25" = to 1 1/4" ?

In real math, yes. In tire math, no. I don't think it matters in 27", but many other diameter tires have differences between the fractionally-expressed sizes and the decimally expressed. A good explanation:

http://www.sheldonbrown.com/tire-sizing.html

operator
10-10-08, 10:38 PM
Anyone know the max tire width for a 27 rim (on a motobecane nomade)? My son blew out the front tire on his bike today (Conti gatorskin 27x 1.25) so I need to replace it and the rear.

Since he is fairly new to roadbiking (coming from dept store bmx and a trek MTB) he is sometimes a bit shaky or tends to weave. I was wondering if a slightly wider tire might help some.

So is 1.25" the widest tire made for 27" wheels?

Thanks in advance for the help.

Measure the actual width of the rim and post it. Tires cannot be narrrower than the width of the rim. Most 27" wheels i've seeen should take at least 28/32c'.

wrk101
10-11-08, 07:13 AM
Niagara sells two different tires in 27 - 1 3/8. They are less than $10 each, cheapest one is $7.63. www.niagaracycle.com

HillRider
10-11-08, 07:20 AM
Even if you find wider tires, they won't improve your son's riding skills. They will offer better protection to the rims if he tends to hit things but they won't keep him steadier or prevent weaving. I'd work on his riding techniques first.

CollectiveInk
10-11-08, 08:17 AM
Even if you find wider tires, they won't improve your son's riding skills. They will offer better protection to the rims if he tends to hit things but they won't keep him steadier or prevent weaving. I'd work on his riding techniques first.

First off, thanks to everyone's input (even Chuck who's acid replies served to enlightened me to the fact that a quarter inch doesn't always equal a quarter inch. :twitchy: )

Hillrider: my thinking was a wider tire would add my stability. I have been trying to help him with his skills while we ride (pedal smoothly, pick a good spinning cadence, look ahead instead of straight down or to the side - that's when he gets the most weave-iest, etc.) Of course, coming from dear old dad it's just frustrating to him. :notamused: BTW, I'm not yelling at him, or belittling him, and have tried to explain te logic behind all the advice.

Anyone know of any good tips or tricks to help someone improve their skills other than wider tires that may not help? :bang:

Panthers007
10-11-08, 10:00 AM
xx

BCRider
10-11-08, 10:43 AM
Getting back to the tire width being used to try to stabilize the bike... No, it won't help. Certainly not that small an amount of change. The twitchiness of the steering comes from the frame geometry with the steeper head angle and smaller trail distance compare to any of the more recent MTB's. Just get a new 1.25 tire and let him ride more to get a feel for the lighter steering of a road bike. He's probably just not used to the size compared to his BMX. Or you've got him on too large a bike if he's still young and hasn't grown into the bike size yet.

Retro Grouch
10-11-08, 03:52 PM
Isn't 1.25" = to 1 1/4" ?

Not of you're talking about bicycle tires.

CollectiveInk
10-11-08, 05:52 PM
Set up an obstacle course and offer him money if he makes it through. Then you'll know, when he brings the bike back in a trash-bag, that he's lazy and at fault.

Dude? Really? Is your life so boring that you have to crap on people's threads asking for advice? Not that it matters, but my son is probably less lazy than you are.

CollectiveInk
10-11-08, 05:55 PM
Getting back to the tire width being used to try to stabilize the bike... No, it won't help. Certainly not that small an amount of change. The twitchiness of the steering comes from the frame geometry with the steeper head angle and smaller trail distance compare to any of the more recent MTB's. Just get a new 1.25 tire and let him ride more to get a feel for the lighter steering of a road bike. He's probably just not used to the size compared to his BMX. Or you've got him on too large a bike if he's still young and hasn't grown into the bike size yet.

Thanks to all for the advice.

I did get some 1.25 tires today and spoke to a cycling coach. I'm going to have my son help mount the tires as a learning experience. The coach is going to help refine his bike fit, and work with him on his skills. I figured this might work since he takes soccer advice from his coach vs me... perhaps cycling will be the same.

Jeff Wills
10-11-08, 10:22 PM
Thanks to all for the advice.

I did get some 1.25 tires today and spoke to a cycling coach. I'm going to have my son help mount the tires as a learning experience. The coach is going to help refine his bike fit, and work with him on his skills. I figured this might work since he takes soccer advice from his coach vs me... perhaps cycling will be the same.

It is a child's prerogative to ignore a parent's advice. This is why my wife and I have cats. (Don't have to teach 'em how to drive, don't have to send 'em to college...) :roflmao2:

As to tire sizes- your discovery that 1 1/4" does not equal 1.25" is just the start. Read the Sheldon Brown article- it's a long, dark, sordid story.

Jeff

Panthers007
10-11-08, 10:30 PM
Last time I offer ANY idea in this craphole forum.

CollectiveInk
10-11-08, 10:33 PM
Last time I offer ANY idea in this craphole forum.

THANKS! :thumb:

Unless of course it's constructive... then offer away. Saying or implying a person's child is lazy simply because he/she lacks riding skills is not constructive.

DannoXYZ
10-12-08, 04:28 AM
Sounds like your son could relax his arms and shoulders a bit. If he's turn the bike when he turns his head, he needs to keep his shoulders aimed forward and turn only his neck. You can practice with him off the bike. Have him place both his hands on the table and practice turning his head without moving his hands.

I don't know how old he is, but I've seen a lot of kids weave dangerously out into traffic when they hear sudden sounds from the side, like someone calling to them as they ride past.