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  1. #1
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    Why different fork travel on different bikes?

    This is probably a noob question, but oh well...

    I noticed that various Spesh bikes have various travel on the fork, and generally the hardtails have less travel than the full suspension bikes (stumpy is an example). Why is this? I have a Rockhopper HT and am considering upgrading the fork to something from Fox, but am not sure how much travel to go for.

    thanks
    jonathan

  2. #2
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    Different frames are designed for different types of fork. For example, downhill and freeride bikes such as the Demo series or the BigHit series, based on their intended riding purpose, require much more travel than, say, an Epic or Rockhopper. This isn't just for Specialized, but any bike maker. When you put a large travel fork on a bike that isn't designed for it, it can really screw up the geometry and put unnecessary stress on the frame (which could lead to a failure).

    I have an older model Rockhopper and I, too, want to upgrade the fork. The fork on there now is only 80 mm of travel (an old Rock Shox Judy C) and I'm thinking about moving it up to about 100 mm. Fortunately for guys like us, there are lots of forks out there that can do this. I'm not entirely sure which Fox forks will fit, but I do know that their 32 TALAS forks have an option for 100 mm (up to 140 mm).

    Don't worry about noob questions either, we all start somewhere! I'm sure someone will be able to give you much more precise information than I could about the way it messes up the geometry, so I'll let someone else pick up my slack
    Get a bicycle. You will not regret it if you live. ~Mark Twain

  3. #3
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    Thanks for the response.

    My Rockhopper has a 100mm RockShox fork now, so I suppose swapping to something like a Fox F100 would be ok.... those things are pricey though.

  4. #4
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    Yea they sure are. I have an 07 Fox Talas on my other bike and it took lots of saving to get it

    Here is a good thread if you want some ideas:

    The All Mountain Hardtail Thread. Post up yours.
    Get a bicycle. You will not regret it if you live. ~Mark Twain

  5. #5
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    I would highly recommend Fox forks. I have used Rockshox and Marzocchi before, but nothing feels as good as Fox. I picked up a lightly used 06 Float 120 for only $220 locally. Look around and if you are not in a hurry you can find a great deal, especially if it's a take-off from a new bike.

  6. #6
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    Sounds good. What's the trick to measuring how long I need the steerer tube to be?

  7. #7
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    Well, it can't be shorter than the head tube length, plus that of the stem. Most people recommend it to be SLIGHTLY shorter than the tip of the stem when everything is installed (so when you take the top cap off, there is about a mm between the top of the steerer tube and the top of the stem). You can have it longer though, some people even have it sticking up out of the stem. Just remember that the steerer tube has to run through the head tube and then the stem has to sit on top of that. If you have one that is too long, you can either cut it or use spacers to get that "perfect fit". Spacers are also handy for putting the stem at a comfortable height for your arms.
    Get a bicycle. You will not regret it if you live. ~Mark Twain

  8. #8
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    theres a night and day difference between the old RS recon on my xc and the fox F100 on my epic, no brake dive softer smoother stiffer better in every way, i dont think ive even had to adjust it since i got it

  9. #9
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    Quote Originally Posted by ilmaestro
    This is probably a noob question, but oh well...

    I noticed that various Spesh bikes have various travel on the fork, and generally the hardtails have less travel than the full suspension bikes (stumpy is an example). Why is this? I have a Rockhopper HT and am considering upgrading the fork to something from Fox, but am not sure how much travel to go for.

    thanks
    jonathan
    Why is it you want to upgrade? What is wrong with what you have on there now? I am guessing an entry level fork (Tora or maybe even....gasp....Dart.... ), so I would be careful not to put the blame entirely on the fact that it is from RockShox. One of the best value 100mm forks you can get right now is the RockShox Reba....very nice ride, and not that pricy (saw them online for less than $400). That thing is still raced by 1000s of XC racers, just as an example, and will be a significant upgrade over anything stock on a Rockhoppper.
    (And yeah, the 2008 Fox stuff is supposed to be very nice as well, I have ridden a 36 Talas RC2, and can confirm that it is indeed a fantastic fork - but that is for an aggressive all-mountain rig discussion, not this one here...)

    But that brings back the original question: why are you upgrading? If you have "outgrown" your Rockhopper, chances are you will not find what you are looking for with just a fork upgrade. Consider moving up to a Stumpy or equivalent....? You will get a whole new league of frame and component quality, and a bike that will do a lot more for you as you progress (HT or full sussy).

    Defintely do not put a 100-140mm Talas on the Rockhopper. It will not tolerate it from a geometry point of view (unless you intend to ride it only in the 100mm position, which negates its purpose), and I'm pretty sure the frame warranty will be voided as well (with good reason). The reason is that the bike was made for a particular fork length - modifying it too dramatically will raise the steerer-tube, raise the BB, slacken the head angle, change the seatpost angle, it may cause a generally strange rider position, and put a lot more stress on the frame while riding (not to mention that fact that the bike may start behaving funny as well). I believe going from 100 to 120mm may be tolerated on a Rockhopper, but nothing more than that.

    In conclusion: get a RS Reba if you are looking for a good value upgrade, to improve the ride you currently have (smoother yet stiffer, great adjustability, lockout), OR change the bike if what you really need is something to tackle more engaged rides.
    Last edited by Iceman2058; 03-23-2008 at 06:20 AM.

  10. #10
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    that is a good post by Iceman, the Reba is a great fork at a great price, i was going to put one on my xc but i decided to sell the bike and get an epic instead which i love, but im climbing the walls waiting for my SX to arrive, i want to hit jumps and drops, grrrr

  11. #11
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    Quote Originally Posted by darkest_fugue
    that is a good post by Iceman, the Reba is a great fork at a great price, i was going to put one on my xc but i decided to sell the bike and get an epic instead which i love, but im climbing the walls waiting for my SX to arrive, i want to hit jumps and drops, grrrr

    ahahahahaha...I can tell you have the freeride itch DF!!!

  12. #12
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    well when i went to the small downhill park with 2 friends it just gave me good memories of being a kid with my cheapo bmx, it was also FUN!!! yes i cant wait, i wont sell my epic though, it gets me round the resort faster than a car ha ha

  13. #13
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    Quote Originally Posted by Iceman2058
    Why is it you want to upgrade? What is wrong with what you have on there now? I am guessing an entry level fork (Tora or maybe even....gasp....Dart.... ), so I would be careful not to put the blame entirely on the fact that it is from RockShox. One of the best value 100mm forks you can get right now is the RockShox Reba....very nice ride, and not that pricy (saw them online for less than $400). That thing is still raced by 1000s of XC racers, just as an example, and will be a significant upgrade over anything stock on a Rockhoppper.
    (And yeah, the 2008 Fox stuff is supposed to be very nice as well, I have ridden a 36 Talas RC2, and can confirm that it is indeed a fantastic fork - but that is for an aggressive all-mountain rig discussion, not this one here...)

    But that brings back the original question: why are you upgrading? If you have "outgrown" your Rockhopper, chances are you will not find what you are looking for with just a fork upgrade. Consider moving up to a Stumpy or equivalent....? You will get a whole new league of frame and component quality, and a bike that will do a lot more for you as you progress (HT or full sussy).

    Defintely do not put a 100-140mm Talas on the Rockhopper. It will not tolerate it from a geometry point of view (unless you intend to ride it only in the 100mm position, which negates its purpose), and I'm pretty sure the frame warranty will be voided as well (with good reason). The reason is that the bike was made for a particular fork length - modifying it too dramatically will raise the steerer-tube, raise the BB, slacken the head angle, change the seatpost angle, it may cause a generally strange rider position, and put a lot more stress on the frame while riding (not to mention that fact that the bike may start behaving funny as well). I believe going from 100 to 120mm may be tolerated on a Rockhopper, but nothing more than that.

    In conclusion: get a RS Reba if you are looking for a good value upgrade, to improve the ride you currently have (smoother yet stiffer, great adjustability, lockout), OR change the bike if what you really need is something to tackle more engaged rides.
    Thanks for the response.

    I was only considering Fox since I've tried a few on friend's bikes and liked them. Haven't tried a Reba yet but I'll see if I can try one. I'm still liking my bike good for now. The next bike I get will probably be FS, but I'm in no hurry.

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