1. The most important thing about buying a new bike is to make sure it fits. The only way you'll know if the bike is right for you is to size up the bike and make sure that the bike's geometry matches your body's geometry. Ask questions and do some research.
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2. If possible, try to find a shop that will let you demo the bike on real dirt. Five minutes in a parking lot won't cut it. You wouldn't buy a car without a real world test drive, and a bike should be no different.
3. Don't belive the hype. Just because your favorite rider or best friend rides a certain bike, that doesn't mean that's the best one for you. Have an open mind and be realistic about your needs and ability.
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  1. #1
    Bearded highlighter
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    Front/ Rear Tire size

    Why is it that some people run a wider tire in the front than in the rear?
    I currently run tires that are the same width but feel that my rear could stand to be wider because when climbing I often lose traction but have more than enough traction when turning and stopping.
    Thanks for the help guys.

  2. #2
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    Control,plain and simple.A lot of people will run 1.9's in the rear for the better rolling resistance and to drop some weight,but you need at least 2.0's on the front if you do anything more then paved trails.2.0 equals more contact which means better grip and control.I plan on doing this myself when I get new tires.Control is much more important up front because it affects your steering and braking.This applies to bigger tires also,like running 2.0's in the rear and 2.3's in the front.Anyways,you get the picture.

    I'm no expert so maybe someone can correct me if I'm wrong?
    Last edited by CRed; 07-30-2008 at 02:08 AM.

  3. #3
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    There is another factor as well....

    clearance. Most modern XC/Trail forks will accomodate up to a 2.3" tire. But most of the MTBs sold are still XC oriented in most cases. So the frame may not have clearance for as large a tire in the rear.

    Personally I've never been able to notice any big benefit to the practice. But there are those that swear by it.

    Good Dirt
    "I do whatever my Rice Cripsies tell me to!"

  4. #4
    Happy in Happy Valley
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    Quote Originally Posted by EHCRain
    Why is it that some people run a wider tire in the front than in the rear?
    I currently run tires that are the same width but feel that my rear could stand to be wider because when climbing I often lose traction but have more than enough traction when turning and stopping.
    Thanks for the help guys.
    What tire are you running currently?

    Since you're in the beginner's corner I'm going to go out on a limb and say that you are a beginner? I'd recommend you stick with what you have and work on technique before you spend $$ on tires. Unless you're running semi-slicks or something crazy.

    Pay special attention to the position of your body while climbing.

  5. #5
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    Quote Originally Posted by EHCRain
    Why is it that some people run a wider tire in the front than in the rear?
    I currently run tires that are the same width but feel that my rear could stand to be wider because when climbing I often lose traction but have more than enough traction when turning and stopping.
    Thanks for the help guys.
    If you are having problems with losing traction on climbs, I would say that is mostly technique. A different tire tread could give you some better grip as well, but more width won't help much for climbing.

    As for why most people use a bigger front tire, think about this:
    If you lose grip on the rear while going around a corner you can still steer with the front and drift through. If you lose grip on the front tire you no longer have any control of your bike. Additional grip is much more important on the front, so most people sacrifice some weight to use a bigger front tire with more grip.

  6. #6
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    The theory came from motocross...

    Bigger tire in front to float over the fines and grip in the corners. Smaller tire in back to dig through the sand and drive the bike.

    I think it's bunk for mountain bikes. If you get better control and traction with the larger tire in front, why not run a larger tire in back? You don't have a gas engine powering through and digging down to find hardpack.

    Weight benefits? Whatever. If you're in good enough shape that a few grams make a noticable difference, then you're likely a sponsored racer and you're running thin tires in the front as well as the rear.

    Traction and control are more important than weight, to me.

    The expection to this opinion is that on a few (mostly XC race specific) bikes, you're limited on the tire width in back. Most bikes however, can fit a higher volume tire in back.

  7. #7
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    Quote Originally Posted by Ken in KC
    Bigger tire in front to float over the fines and grip in the corners. Smaller tire in back to dig through the sand and drive the bike.

    I think it's bunk for mountain bikes. If you get better control and traction with the larger tire in front, why not run a larger tire in back? You don't have a gas engine powering through and digging down to find hardpack.

    Weight benefits? Whatever. If you're in good enough shape that a few grams make a noticable difference, then you're likely a sponsored racer and you're running thin tires in the front as well as the rear.

    Traction and control are more important than weight, to me.

    The expection to this opinion is that on a few (mostly XC race specific) bikes, you're limited on the tire width in back. Most bikes however, can fit a higher volume tire in back.
    You have a point. For technical riding, really fast downhills, etc I want as much grip as I can get from both tires to keep me under full control.

    But I do disagree a little bit:

    For normal riding (not just racing) I don't want to have an 800g tire on the back of my bike, especially for long climbs or swoopy ST. I can tell a difference because I don't have a gas engine doing the work for me; just my legs. I'm in decent shape, and don't want to handicap myself further. A larger front tire adds enough grip for my preferences for normal trail riding without having to beef up the rear as well.

    You are correct that the MX tire theory doesn't make sense for mountain bikes and that is exactly why no one follows it. The people here who ride on sand are using wide tires front and back for lots of float. I don't expect a 2.1 in the rear to bite in any more, I just expect it to pedal easier.

  8. #8
    Rod
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    if you're losing rear traction while climbing stay seated or lean further back to keep more weight on the rear tire.
    There is not much choice between rotten apples.

  9. #9
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    We'll agree to disagree....

    Quote Originally Posted by boomn
    You have a point. For technical riding, really fast downhills, etc I want as much grip as I can get from both tires to keep me under full control.

    But I do disagree a little bit:

    For normal riding (not just racing) I don't want to have an 800g tire on the back of my bike, especially for long climbs or swoopy ST. I can tell a difference because I don't have a gas engine doing the work for me; just my legs. I'm in decent shape, and don't want to handicap myself further. A larger front tire adds enough grip for my preferences for normal trail riding without having to beef up the rear as well.

    You are correct that the MX tire theory doesn't make sense for mountain bikes and that is exactly why no one follows it. The people here who ride on sand are using wide tires front and back for lots of float. I don't expect a 2.1 in the rear to bite in any more, I just expect it to pedal easier.
    If I'm ripping swoopy singletrack, I want both tires to grip indentically. A two wheel drift is much more controlled than the rear wheel not hooking up.

    Regarding weight: Again, unless you're a racer, I question whether weight is a justifiable reason. If it is, then having a thinner front tire follows the same thought process.

    The difference between a fat and thin tire really isn't all that much. A gram is basically a paperclip. Assuming a 200 gram difference, that's a small box of paperclips in weight vs. having much better traction and more pinch flat resistance.

    Everyone has their own preference. I've found that I prefer consistent traction and identical performance on both tires is more important to me than shaving a few grams.

  10. #10
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    Quote Originally Posted by Ken in KC
    If I'm ripping swoopy singletrack, I want both tires to grip indentically. A two wheel drift is much more controlled than the rear wheel not hooking up.

    Regarding weight: Again, unless you're a racer, I question whether weight is a justifiable reason. If it is, then having a thinner front tire follows the same thought process.

    The difference between a fat and thin tire really isn't all that much. A gram is basically a paperclip. Assuming a 200 gram difference, that's a small box of paperclips in weight vs. having much better traction and more pinch flat resistance.

    Everyone has their own preference. I've found that I prefer consistent traction and identical performance on both tires is more important to me than shaving a few grams.
    Yeah, it absolutely comes down to personal preference and local riding. I just want to point out that those of us with different preferences aren't insane or frivolous

    I have no desire to run a small front tire as well, and I don't see how that is the logical result. The idea is that it strikes a balance in weight vs. grip (that some people prefer).

    BTW. 225 grams = 1/2 lb. Another perspective

  11. #11
    Happy in Happy Valley
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    From www.sheldonbrown.com:

    Quote Originally Posted by Sheldon Brown
    Bikes that are used some of the time on loose surfaces often benefit from a wider front tire, with a fairly agressive tread, coupled with a somewhat narrower, smoother rear tire.

    The wide, knobby front tire will provide the all-important front wheel traction. If your front tire skids, it almost always leads to a crash. For riding in soft conditions, such as sand or mud, a wide front tire is essential. If the front tire sinks in and gets bogged down, you're stuck. If the front tire rolls through a soft patch OK, you can generally power the rear through to follow it.

    The narrower, smoother rear tire will have lower rolling resistance. Since most of the weight is carried by the rear tire, rolling resistance is more important on the rear than the front. If the rear tire slips, in most cases the worst that will happen is that you'll have to get off and walk.

  12. #12
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    I lose traction when I am seated and climbing in lower gears, if I stand and stay in a higher gear its not at bad, at most I get half a tire rotation and nothing more. Would staying in a gear higher prevent this?
    I am currently running Kenda Klaws but was looking at specialized Chunders and Hardrockers to replace them.
    Thanks for all the quick relies and helpful advice.

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