Trying to ride my old bike again - confusing rim + tire sizes
#1
Junior Member
Thread Starter
Join Date: May 2017
Posts: 10
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Trying to ride my old bike again - confusing rim + tire sizes
New poster here... 
So I have my College Bike from back in the day...and I never really used it since college. Now I want to start using it again for leisure rides.
I'm having quite a time figuring this out. I managed to fill my rear tire with air using one of these mini bike pumps...despite the Schrader fitting constantly recessing as I pushed this bike pump into the valve...had to practically hold the Schrader valve and push the pump in to fill it with air (this is correct right?) Or should my valve not be flailing in and out of the rim hole?
In any case I tried filling the front tire's air tube..and it would not work no matter what. Long story short I think I may have ripped the schrader valve from the tube
I now need a new "tube".
Rim says this: Weinmann 700c x 28/35c
My Actual TIRE on the other hand says 700 x 38c....
The tube inside says 700 x 35/43c.
I know the first number means diameter of the tire and the 2nd set means width/fatness of tire (I might be wrong).
If my rim only supports up to 35c...why on earth is my tire 700x38c. Isn't that bad?
Anyways super confused what to do.....I can simply get a tube like the one I ripped out but yeah...very lost here guys. Please help

So I have my College Bike from back in the day...and I never really used it since college. Now I want to start using it again for leisure rides.
I'm having quite a time figuring this out. I managed to fill my rear tire with air using one of these mini bike pumps...despite the Schrader fitting constantly recessing as I pushed this bike pump into the valve...had to practically hold the Schrader valve and push the pump in to fill it with air (this is correct right?) Or should my valve not be flailing in and out of the rim hole?
In any case I tried filling the front tire's air tube..and it would not work no matter what. Long story short I think I may have ripped the schrader valve from the tube

I now need a new "tube".
Rim says this: Weinmann 700c x 28/35c
My Actual TIRE on the other hand says 700 x 38c....
The tube inside says 700 x 35/43c.
I know the first number means diameter of the tire and the 2nd set means width/fatness of tire (I might be wrong).
If my rim only supports up to 35c...why on earth is my tire 700x38c. Isn't that bad?
Anyways super confused what to do.....I can simply get a tube like the one I ripped out but yeah...very lost here guys. Please help

#2
Senior Member
Join Date: Feb 2015
Location: Mission Viejo
Posts: 5,446
Bikes: 1986 Cannondale SR400 (Flat bar commuter), 1988 Cannondale Criterium XTR, 1992 Serotta T-Max, 1995 Trek 970
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 1815 Post(s)
Liked 1,965 Times
in
1,205 Posts
Not a problem running 38mm wide tires.
John
John
#3
Really Old Senior Member
Tubes will come in a range of sizes and your appears to be right in the middle.
That's a good place.
If I was looking for a replacement, that's the size I would look for. Small enough to insert easily and large enough to not get stretched too much.
That's a good place.
If I was looking for a replacement, that's the size I would look for. Small enough to insert easily and large enough to not get stretched too much.
#4
Senior Member
I managed to fill my rear tire with air using one of these mini bike pumps...despite the Schrader fitting constantly recessing as I pushed this bike pump into the valve...had to practically hold the Schrader valve and push the pump in to fill it with air (this is correct right?) Or should my valve not be flailing in and out of the rim hole?
How can you be unsure?
A rim has 1 width; where on it did you find this?
Check out sheldonbrown.com/tire-sizing.html to find out what tires your rim can accommodate - after you figure out exactly how wide the rim is.
Not necessarily
#5
Junior Member
Thread Starter
Join Date: May 2017
Posts: 10
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Picture Time!

RIM:

TIRE:

As for filling my 700x38C tires with the 700x35/43C inner tube - The pump (airforce 2 specialized pump) does have a locking lever - but I have to push down on the bike tire to make a connection..as I push down - the Schrader tube also pushes down BELOW the frame of the rim. It doesn't stay still. I only filled up the back tire by holding the Schrader tube...then pushing the air pump in and finally locking it with the lever. Not sure if this is normal...

As for filling my 700x38C tires with the 700x35/43C inner tube - The pump (airforce 2 specialized pump) does have a locking lever - but I have to push down on the bike tire to make a connection..as I push down - the Schrader tube also pushes down BELOW the frame of the rim. It doesn't stay still. I only filled up the back tire by holding the Schrader tube...then pushing the air pump in and finally locking it with the lever. Not sure if this is normal...

#6
Senior Member
Join Date: May 2011
Location: Upstate NY
Posts: 3,794
Bikes: Bianchi San Mateo and a few others
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 634 Post(s)
Likes: 0
Liked 13 Times
in
9 Posts
The label on your rim gives lots of good info that'll help us answer your questions:
With that knowledge, the 38 mm width of your 700c x 38 tires is fine. And the 35-43 mm width range of your tube is the correct size for the tire.
- "700Cx28C/35C" means that you can run 700c tires, and Weinmann recommends tire widths between 28 and 35 mm.
- ETRTO 622x20 is the rim size in ISO/ETRTO notation. It means your rim has a bead seat diameter of 622 mm -- the standard diameter for 700c tires. Your rim's width is 20 mm. According to the ETRTO (European Tyre and Rim Technical Organization), a 20 mm rim will ideally be paired with tires whose width is between 28 and 44 mm wide. According to the ETRTO, Weinmann's 28-35 recommendation is very conservative.
With that knowledge, the 38 mm width of your 700c x 38 tires is fine. And the 35-43 mm width range of your tube is the correct size for the tire.
#7
Senior Member
Join Date: Sep 2010
Location: Roswell, GA
Posts: 8,317
Bikes: '93 Trek 750, '92 Schwinn Crisscross, '93 Mongoose Alta
Mentioned: 30 Post(s)
Tagged: 0 Thread(s)
Quoted: 1437 Post(s)
Liked 1,085 Times
in
720 Posts
As to having to hold the valve stem, if the tube has no pressure there will be nothing keeping it from getting pushed down into the rim, this is normal. So it will need to be held in order to press on a chuck, unless you get a tube which has a threaded stem with a nut to hold it; Continental has such tubes. I how have a chuck which screws on but in the past I have used a needle-nosed pliers to hold the stem.
#8
Senior Member
Join Date: Apr 2010
Location: Elevation 666m Edmonton Canada
Posts: 2,193
Bikes: 2013 Custom SA5w / Rohloff Tourster
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 1078 Post(s)
Liked 233 Times
in
183 Posts
How about a pic of the pump head. There should be a lever to turn to lock the chuck on.
I've never heard of one that doesn't screw on on something.
I've never heard of one that doesn't screw on on something.
#9
Senior Member
As for filling my 700x38C tires with the 700x35/43C inner tube - The pump (airforce 2 specialized pump) does have a locking lever - but I have to push down on the bike tire to make a connection..as I push down - the Schrader tube also pushes down BELOW the frame of the rim. It doesn't stay still. I only filled up the back tire by holding the Schrader tube...then pushing the air pump in and finally locking it with the lever. Not sure if this is normal
The rim both tells you its width: 20, and recommends tire sizes. You can consult tire-sizing.html for its recommendations for a 20. It has only odd numbers; interpolating between the recommendations for 19 & 21 rims, they would be 32-47. SkyDog75 is probably right.
#11
Senior Member
I looked on ETRTO's web site and couldn't find this info. Schwalbe publishes a chart that it claims comes from ETRTO but they must have made a mistake.
#12
Senior Member
Join Date: May 2011
Location: Upstate NY
Posts: 3,794
Bikes: Bianchi San Mateo and a few others
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 634 Post(s)
Likes: 0
Liked 13 Times
in
9 Posts
And even with that aside, the OP's 38 mm tires just barely exceed Weinmann's 35 mm recommendation. They'll be fine.
#13
Calamari Marionette Ph.D
Did someone with a college education really just come to a bike forum to ask how to pump up a tire?
On a bike they have owned for years?

Maybe I just haven't had enough coffee yet this morning.
On a bike they have owned for years?

Maybe I just haven't had enough coffee yet this morning.
#14
Senior Member
Join Date: Jul 2012
Location: Ocala, Florida
Posts: 256
Bikes: 74 Romic, 83 Basso, Lotto, 88 Condor, Prestige MTB, 12 Soma, Groove
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Millennial's, 84% of them have no clue how to check oil, or even open the hood of their cars. I suspect, however, they ALL know how to program their cell phones!
Last edited by skoda2; 05-08-17 at 08:23 AM.