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  1. #1
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    Quick Question - Stem Length?

    New to MBing. What is the minimum stem length (forks) for a Trek Fuel 70? Thanks.

  2. #2
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    What are you....

    refering to when you say stem. Are you talking the "stem" that clamps to the fork and the handle bar. That is the part of the bike that is properly refered to as the stem. Or are you talking about the tube that runs from the crown of the fork up through the head tube of the frame that the stem clamps too? It makes a big difference. The steerer tube is the part that is connected to the fork. The stem is clamped to the steerer tube at one end and the handle bars on the other. So which part are you talking about?

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

  3. #3
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    Thanks Squash. I am talking about the tube that runs from the crown of the fork up through the head tube of the frame. I was looking at a used fork on ebay that was cut to 7" and wasn't sure if that would work for me.

  4. #4
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    If you buy a new fork the steerer tube (not stem, as I think you mean) will (absolutely should anyway) be long enough to fit on your bike. Of course, it depends on your exact stem/headset combo.

    Hope that helps!
    Tim
    I wish I didn't know now what I didn't know then.

  5. #5
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    Okay Dart, that's what....

    I thought but wasn't sure. The steerer tube length required for a given frame varies depending on the size of the frame and between manufacturers as well. So it's tough to say what your minimum would be. For instance I have a Specialized Stumpjumper that is an XL. The minimum steerer length for that bike 9 1/2" including the 3/4" of spacers that I have under the stem. Absolute minimum if I didn't want to use the spacers is 8 3/4". I also have a Trek hard tail in XL and the minimum steerer length for that bike is 8 3/4" with the same stem and spacers. Absolute minimum without spacers is 8". So you see it does vary quite a bit. And that variation is even larger for different size frames.

    But it is easy to figure out what you need. Simply take a tape measurer and measure from the crown of the fork up along the head tube to the top of the stem. Thats your absolute minimum if you intend to use the same stem and the same amount of spacers that you are currently using. Now that's for a fork that you are buying from someone locally that you know, and can actually measure the fork yourself. For something like ebay or out of the adds on this site, my personal rule of thumb for buying a used fork is to add 1/2 to 1 inch to that measurement just to be on the safe side. You'd be amazed at how many people out there don't know the proper way to measure a fork for steerer length. It doesn't happen so much with adds on MTBR, but is not uncommon on ebay. So say you were to measure and your came up with 7 1/4" as your steerer length requirement. Just add an inch and make your minimum 8 1/4". That way you are about 95% sure that you'll get a steerer that will fit or can be made to fit your bike. You can fudge it a little as well, if you find one at 7 1/2 or something like that and are fairly confident that the seller has the measurement right you can go for it. Just remember when using this formula with it's "safety margin", most of the time you'll end up having to cut the steerer down to fit your bike exactly or end up adding a few spacers. But it's better to have to cut the fork steerer down than having one that is too short. You can always cut the steerer down, but you can't add to it!

    Anyway that's how to be on the "safe side" when buying a used fork. And the safety margin is totaly dependant on how comfortable you are with the sellers measurements. So measure yours and add a little to it if you like and go from there.

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

  6. #6
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    Thanks again Squash, tibug. I'm Learning all the time and your explanations helped alot. Okay with your help, and a little research, here's what I did...you tell me what you think. I like to tinker with things so I am redoing the front end. I ordered Marzocchi MX PRO ETA/TAS 100/120, a Chris King Headset, a Thomson Elite X4 Mountain Stem and FSA K-Force Carbon XC Riser Handlebars. I am also putting Avid SD7 levers and brakes on.

    Again, I appreciate your help. I'll know where to look for adivice again.

  7. #7
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    Sounds good to me....

    the MX Pro is a good fork, the Thomson stem is really hard to beat, the FSA bar is light and stiff, the SD7 brakes are about the best bang for the buck vbrakes out there and I've got a King headset that is on it's 4th frame, nuf said! I don't think you could do much better for the money. Upgrades are allot of fun, so have fun with it.

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

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