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Bicycle tires?

  1. Aug 17, 2008 #1
    After riding to work a lot during my internship/REU/whatever thing, I'm back home and want to keep riding anywhere I can. I have an old hybrid mountain/road bike which I really like, but the tires are getting old, especially the back one is getting frayed and I'm getting a bumpy ride for some reason.

    They are 700x35c tires, and I'm having trouble finding them online. I found plenty of 700x32c, but I don't know if that would be good enough. I think 3mm isn't that much, but then again I don't want to wipe out while going down hill on a busy street.

    While we're at it, what size tube should I get? Same as the tire, or slightly smaller?
     
  2. jcsd
  3. Aug 17, 2008 #2

    mgb_phys

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    700x32 will fit perfectly, the rim size is fixed for the diameter.
    The narrower tyre (or tire) will give you better rolling resistance on the road.

    Tubes aren't exactly precise, they normall come in 1-1/2 increments anyway.
     
  4. Aug 17, 2008 #3

    Chi Meson

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    700x32 is no different from 700x35. both are extremely fat for a 700C wheel. That's mountain bike fat on a road bike rim. You could easily use any size down to 25 if you are not going over a lot of loose dirt. And tubes have a lot of overlap (they can stretch) Find a tube that says something like: "700C x28--35". Don't use a tube that does not overlap with your tire size. Pop.
     
  5. Aug 17, 2008 #4
  6. Aug 17, 2008 #5
    Chances are your bike will be fine without lubricant. And if you really think it needs some, just get some WD-40...
     
  7. Aug 17, 2008 #6
    I wouldn't put WD-40 anywhere near my bike. :surprised
     
  8. Aug 17, 2008 #7
    WD-40 is a solvent, not a lubricant. It will dissolve any lubricant I have left on my bike and I will proceed to grind while riding.

    But thanks for playing.
     
  9. Aug 18, 2008 #8

    mgb_phys

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    The only thing that needs regular lube is the chain. Clean it with a chain cleaner then spot any light oil on the sides of the links.
    Putting grease or anything thicker on the chain means grit sticks to it which quickly wears the chain and hub.

    And you're right, don't put wd-40 near anything that already moves. It's for stuff that should move but doesn't.
     
  10. Aug 18, 2008 #9

    chroot

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    Note that he said he's looking for TIRES, not TUBES. Everyone else is correct, though -- you won't notice 3 mm in either a tire or a tube. Get tires that fit the kind of riding you wish to do, though.

    The most important thing about "lubing your chain" is actually not lube -- it's the removal of all the dust and dirt that sticks to the lube and clogs the chain. Clean it very thoroughly with a chain cleaner (a rag will suffice but it's not nearly as good), lube every pin in the chain with a good quality non-greasy lube like ProLink (greasy lubes attract dirt, which you don't want), then wipe it off several times with a clean rag. You really need very, very little lube, and you want it in the pins, not on the outside where it serves no purpose. Excess lube just makes your chain get dirty more quickly.

    - Warren
     
  11. Aug 18, 2008 #10
    Re: Bicycle chain lube?

    Remove the chain completely. Clean with a sprayed solvent such as Varsol. Allow to dry. Submerge the chain in quality gun oil (or Marvel Mystery Oil) in an ultrasonic cleaning vat for several hours. Remove, wipe off excess and reinstall. Repeat as needed, depending on use in dirt.
     
  12. Aug 18, 2008 #11

    mgb_phys

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    Wow a new religous war!
    By sides of the chain, I meant you need to get oil between the side plates of adjacent links where they move over each other. You don't put oil on the rollers - ie down the middle of the chain. As chroot says you want almost no oil, just touch the tip of an oil-can to each link.

    If it's very bad or at all sticky - consider getting a new chain, they are < $10 and save a new cassette. If you commute everyday it's worth replacing the chain every year, depending on how bad the roads are in winter.
     
  13. Aug 18, 2008 #12
  14. Aug 18, 2008 #13

    mgb_phys

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    The oil will be fine - don't know if it is really that much better than the old "3 in 1" from your local hardware store.

    Most modern bottom brackets with plastic cups don't need regreasing, the pedals only need greasing if they stick. It's also worth putting a few drops of oil in the ends of the brake/gear cables where they enter the sleeve, to try and keep water from buildign up there.
     
  15. Aug 19, 2008 #14
    Okay, so I ordered 2 tires, 2 tubes, some tire levers, and some lube.

    Today, I got the tubes, levers, and lube. I look at my order and it says it's all shipped with the same tracking number.

    I look at the UPS tracker and it says the package only weighted 1.4lbs, which is about the weight of a single tire.

    Does it happen often that UPS will only give part of a package and give the rest the next day (say they didn't notice or something), or do I need to contact the company and tell them to actually send the tires this time?
     
  16. Aug 20, 2008 #15

    Chi Meson

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    I use that product. There is one trick to them: get the chain as clean as possible. There's the proper way (remove the chain, soak in kerosene, scrub with a toothbrush, rinse in clean kerosene, hang to dry) and there is the gritty commuter method (I commute 15 miles every day in all weather):

    You can use (gasp) WD-40 first to dissolve the oil/grease that is already on the chain. I spray the chain (old rag behind the chain keeps the stuff off the bike), then crank the chain backward through the rag which is now clasped around the chain. repeat, repeat. Keep moving the rag as it turns black, continue until the chain is dry. It won't be perfectly clean, but you're commuting, not racing, right?

    I personally wouldn't use "3-in-1" oil. It doesn't last long, it gets gummy and picks up grit, and then you get cakes of black stuff you need to get out from inside the gear cluster.

    When "dry lube" goes on a clean chain (make sure it gets inside all links) you will not have to relube for months. I'm serious. The liquid in the bottle is essentially a solvent like WD-40. After the solvent dries, it leaves a dry coating on the metal. This coating does not pick up anywhere near as much grit, and it lasts through more than a few wet-commutes. I last lubed my commuter bike in February.

    Wheels and pedals have sealed bearings (unless the bike is more than 15 years old, or really cheap) so they do not need to be relubed. You could, but you'd need special tools. The only other thing you might lube once a year are the cables, letting a few drops of lube dribble down the cables into the sheathing.
     
  17. Aug 20, 2008 #16

    Chi Meson

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    I'd wait another day or so. If you bought a 1.4 pound tire, well, jeez...

    Often, mail-order items are "direct shipped" from the manufacturer, so different items will come in different boxes from different places, yet they will still be part of the same order. Look on the packing slip to see if anything is marked "BO" for "back-order," which means they will send them when they get them.
     
  18. Aug 20, 2008 #17
    Well the tires were like 800grams each, which is over a pound. It said they were "shipped" and had the exact same tracking number, which is what is confusing me. If I get something as part of two packages, they've always had different tracking numbers.
     
  19. Aug 20, 2008 #18

    Chi Meson

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    OK, I guess I've never had 700C knobby tires.

    It wouldn't hurt to call the company, even if the other bits are on their way. It would be a good thing for them to make it clear if things are shipped separately.
     
  20. Aug 20, 2008 #19
  21. Aug 20, 2008 #20
    It could be that the shipments are from different locations.
     
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