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Discussion Starter · #1 ·
IDK if any of you will remember my original post... I live in Michigan and this year I started to commute to the school where I teach 6th grade.

I purchased a DIVERGE bike back in late November.

Last week, I was riding on pretty much all wet pavement. On my commute I cross a 30 ft long wooden train bridge daily. Last week the bridge was covered with snow...but the pavement was all just wet. Well...that sign "caution bridges and overpasses may be icy" that has a whole lot more meaning to me now. Ugh. I was half way over the bridge and could feel little to no traction under me. And then, it happened, the whole bike went out from under me. It happened so quickly I coudn't react. I lay there thinking my leg was broken...no, for sure my arm or shoulder was broken. Then I told myself to pick my pansy self up and get off the ice. Happy to report nothing was broken. Maybe my ego. For the past two weeks...I have walked my bike over that bridge. Several times I can hardly keep myself up. I do not have spiked tires..and don't think that would help with this situation. The bruise I have on the inside of my knee is amazing...and yet I have no idea how I got it.

I am loving riding to work in all weather conditions. My principal has come and insisted that he throw my bike in his truck and give me a ride home. I decline politely and tell him how much I really love the ride.

The point of this post is last week I was riding between 13mph and 15mph and I was exhausted. I don't know why. I was having a heck of a time almost like I was in a quagmire. I'm wondering if my tires can be low. I unscrewed the cap and the valve on the tire is unlike anything I am familiar with. It has a gold nub that if I twist it will move up the stem and if I twist the other way I can release air. IDK how to add air or how to check the tire pressure. Any help would be much appreciate.

Thanks in advance for any and all advice. You all have been such a great help to me.

Jackie
 

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Pathlete and Pedalphile
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IDK if any of you will remember my original post... I live in Michigan and this year I started to commute to the school where I teach 6th grade.

I purchased a DIVERGE bike back in late November.

Last week, I was riding on pretty much all wet pavement. On my commute I cross a 30 ft long wooden train bridge daily. Last week the bridge was covered with snow...but the pavement was all just wet. Well...that sign "caution bridges and overpasses may be icy" that has a whole lot more meaning to me now. Ugh. I was half way over the bridge and could feel little to no traction under me. And then, it happened, the whole bike went out from under me. It happened so quickly I coudn't react. I lay there thinking my leg was broken...no, for sure my arm or shoulder was broken. Then I told myself to pick my pansy self up and get off the ice. Happy to report nothing was broken. Maybe my ego. For the past two weeks...I have walked my bike over that bridge. Several times I can hardly keep myself up. I do not have spiked tires..and don't think that would help with this situation. The bruise I have on the inside of my knee is amazing...and yet I have no idea how I got it.

I am loving riding to work in all weather conditions. My principal has come and insisted that he throw my bike in his truck and give me a ride home. I decline politely and tell him how much I really love the ride.

The point of this post is last week I was riding between 13mph and 15mph and I was exhausted. I don't know why. I was having a heck of a time almost like I was in a quagmire. I'm wondering if my tires can be low. I unscrewed the cap and the valve on the tire is unlike anything I am familiar with. It has a gold nub that if I twist it will move up the stem and if I twist the other way I can release air. IDK how to add air or how to check the tire pressure. Any help would be much appreciate.

Thanks in advance for any and all advice. You all have been such a great help to me.





It's a presta valve. You'll need a pump with a presta head. Turn the "gold nub" counterclockwise to open it. Install pump head. Pump up to desired pressure. Remove pump head and turn "gold nub" clockwise to close. Make sure you don't press down on the "gold nub" when closing or you'll let out the air you just put in. "Gold nub" is the valve stem core.
 

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Discussion Starter · #4 ·
Thanks. Do I need to go to bike store to get that special pump? UGH. Wonder why when they sold me the bike they didn't explain this to me? I really appreciate your help.
 

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Discussion Starter · #5 ·
Thanks. I guess I need to look at youtube. Never think of that. Can I just use my regular bike pump. It looks like she is using one similar to mine that I use on my Mt. Bike.
 

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Cranky Old Bastard
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That video doesn't show that you need a special pump and pressure gauge for presta valves. The easiest solution is to get an adapter like this: Nashbar - Welcome!

Any bike shop will have them.

Edit: And a lot of pressure gauges don't go high enough for bike tires. One like this: Nashbar Dial Tire Pressure Gauge has heads for both types of valves.
 

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Pathlete and Pedalphile
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Thanks. Do I need to go to bike store to get that special pump? UGH. Wonder why when they sold me the bike they didn't explain this to me? I really appreciate your help.
Most floor pumps come with dual heads, one side for schrader valves and the other side for presta. Just get one of those.
 

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Discussion Starter · #8 ·
Well, I went out to garage. Grabbed my Schwinn pump. On the side it has two stickers one for each type of valve. So, I unscrewed the dust cap, and unscrewed the valve. Pushed a bit to release air. Attempted to put on nozzel from air pump....all I did was let all the air out. Now...I have no air at all in the tire. I'm so bummed. IDK if there was an adapter or something to go with this pump. It is fairly new. Has a gauge that is digital that tells you PSI. Feeling like every thing I try is an adventure of learning.
 

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Forever a Student
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Feeling like every thing I try is an adventure of learning.
And you're just getting started.

Look around for instructions for that pump, it won't be too hard once you figure it out but it might be harder than you're thinking at first.

Know anybody that rides bikes? That would help. Have them come over for a bit and show you the simple things.

You'll need to know how to change a tube once you figure out how to air it up.
 

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Discussion Starter · #10 ·
Just my neighbors who also just bought mountain bikes this summer. They have the regular valve. I went to Target and got a new pump. My back tire was down to 50PSI so I figure the front was probably like that as well.

Is that what was making it feel like I was riding in quick sand??? What would cause them to loose air? Do I have a leak or is it from the change in weather. It was in the 20's here and the past 4 days in the 40's-50's.

I don't really know people that ride bikes. That is why I came here. LOL.
 

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Pathlete and Pedalphile
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Riding with that low of pressure will make it feel that way. You will lose pressure fairly quickly, a lot of riders fill their tires before each daily ride.
 

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Pathlete and Pedalphile
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Why will my pressure go down? It is a brand new bike. Well, I bought it in November....
Tubes are porous. You're putting high pressure into a low volume area. It escapes through the pores. Some thicker tubes will hold air longer.
 

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Well, I went out to garage. Grabbed my Schwinn pump. On the side it has two stickers one for each type of valve. So, I unscrewed the dust cap, and unscrewed the valve. Pushed a bit to release air. Attempted to put on nozzel from air pump....all I did was let all the air out. Now...I have no air at all in the tire. I'm so bummed. IDK if there was an adapter or something to go with this pump. It is fairly new. Has a gauge that is digital that tells you PSI. Feeling like every thing I try is an adventure of learning.
The nozzle pressed the valve down, letting the air out. Obviously, the nozzle was too large in diameter or it would have sealed on the valve stem and no air would have leaked out. :idea:

Were you sure the nozzle wasn't the one for the wider shraeder valves like on car tires? If so, the Nashbar adapter mentioned above would be the solution. If the pump nozzle felt "tight" over the valve stem, then either the pump wasn't locked onto the valve using the lever on the nozzle that will crimp it securely, or the rubber washers in the nozzle are hardened with age or worn out, won't seal, and the air leaks out.

As others have said, the higher the pressure, the faster air will leak out over a couple of days. On a 28 or 25mm tire pumped up to 90 psi, air will leak out and it will ride noticeably softer and sluggish at even 80 psi. So every two days, if not every ride, skinny tires need to be topped up.

So buy a new floor pump with the smaller diameter chuck hole that seals on the presta valve when pressed down opening the valve. The attached gauge will tell you where you're at. The pressure is too high to determine accurately by pinching the tire with the hand. They should feel "rock hard."

Generally speaking, the heavier the rider + luggage, the larger the tire and/or the higher the pressure. For a 120 # person riding 25mm tires, 90 psi in back and 85-90 in front would give a great ride. Light weight rider could get away with less pressure on larger diameter tires, but generally not below at least 65 psi.

Steel belted car tires hold pressure for months, largely because the pressures aren't that high, 30-35 psi, and the rubber is way thicker than a bike tire inner tube.
 

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Banned Sock Puppet
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Hi!

Sorry to hear about your recent mishap, but glad nothing was seriously hurt except your pride. :) So far, everything said above is good advice.

At 50PSI rear, it is no wonder you were getting a real workout! And not surprising if you haven't aired up in 2 months. You should be checking and re-inflating your tires AT LEAST once a week. Also keep in mind that when your pressures are low, you are much more likely to get a pinch flat!

What pressures you should use is open for much debate and I'm sure others here will chime in. Ideal pressures depend on what size tires you are using and your weight. Personally, I like to use a front pressure that is at least 20PSI less than the rear. It makes the handlebar vibrations much less and you are also less likely to lose control on wet or icy surfaces (OK, that didn't help you that time!) or if you hit something. The rear tire is where most of your weight is and also where your drive forces are. The front steers the bike, so you don't want that one to be as hard.

Here is a link to a site where you can enter your tire size and your weight (weight includes fully clothed rider, bike and anything you are carrying. So if you weigh 120lbs in your birthday suit, you most likely weigh 130-135lbs+ with winter clothes, boots, etc. Add around 20lbs for the bike. Then whatever you are carrying - 2 full water bottles, backpack full of school textbooks, etc. That will get your weight up there. Use the 2nd box with the heading "Weight of (Fully-dressed) Rider & Bike":

Bicycle tire pressure calculator

Any more questions, please feel free to ask!
 

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Discussion Starter · #18 ·
Wow! Thanks for all that great information. I do ride somedays with over 50lbs on my back. Snow boots, two layers of everything, light down coat covered with a wind breaker, facemask, helmet...on and on and on.... Books, clothes, coffee, water bottles etc. I thought is was the cold, the wind, the dark gray skies....but then in the cold wet rain...I thought it can't be getting this much tougher. I have to be getting into better shape. I come home after riding 30-40 miles. Work out on weight machine then run on treadmill for another 30-40 mins. I just couldn't imagine that I was getting so out of shape that I could hardly make it home. LOL. Today was a breeze. It was cold, wet, windy and I have probably 80lbs in my backpack tonight. I was so thankful I learned about air pressure in my tires. I would press on them and they felt fine. After filling them up late last night I could really tell the difference.

Thanks for taking time to give me this great advice.
 

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Ok...what
is a laytex tube?
Latex tubes are white or cream colored. They're lighter than butyl rubber tubes which are black, and also twice as expensive. They lose air twice as fast as butyl rubber. Get the rubber ones! They're also much more easily patched in case of a flat.
 
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