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
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    Offset sea vs longer stem

    Hi.
    I know this has been discussed a lot but I couldnt find a clear answer to my specific situation. I bought a small Gt Karakoram like 3 weeks ago and everytime I ride it I feel like me and my *ss want to be seated farther back in order to be in a comfortable position (dont know if you get me). So to achieve this I should buy a longer stem or an offset seatpost? Maybe both to mantain some uniformity?

    Thank you in advance

  2. #2
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    Wider bars will also eat up space.
    I would go setback seatpost with seat back on rails first.
    Last edited by eb1888; 06-12-2014 at 06:42 AM.

  3. #3
    Hi There!
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    Am I missing something? Wouldn't a longer stem make you even more forward?
    NTFTC

  4. #4
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    If the bike handles well off-saddle, the stem is probably correct.

    If you have a feeling that you want to move your butt to the rear, it's also probably correct. But I'd look more at why you feel your butt should be more to the rear. Do you have too much weight on your arms? Do you slide forward on the saddle and have to constantly correct your position? Could be that you just need to tilt the nose of the saddle up a slight bit.

    With the slack angles of mountain bikes, I would imagine it's a rare case that you need a setback seatpost for comfort. Most people use them just to get more traction in the rear and a front they can unweigh more easily.

  5. #5
    I'd rather be on my bike
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    How tall are you OP? I have a feeling that the bike might be too small for you.
    '13 FELT TK3 48:15
    Fixed gear - but not a hipster
    2014 miles - 1088/2500

  6. #6
    Fat-tired Roadie
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    I feel like it's hard to find a bike that doesn't ship with a setback post. But if you don't have one, try it. It's about a $15 part if you want it to be. Make sure to get the right diameter.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  7. #7
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    Setback posts are sometimes used to align the knee to the pedal spindle (KOPS) but if I read between the lines correctly the bike might be small for the OP and he's trying to compensate by moving back on the seat.

    If that's the case the setback post will help, don't change the stem.

  8. #8
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    Because you stated that you got a small GT, the top tube may be a little too short for you. You may be correct in that you need an offset and a longer stem, but that may come in steps. The comment about balance is what is important.

    For me I start with an approximate knee over the pedal spindle just to get an idea where to put the seat as a starting point. From my experience and from other posts, there a lot of people who prefer their knees to be slightly behind the pedal spindle, but you will have to figure that out as far as comfort/power combination. If you can't get the seat back far enough to even get your knees over the spindle, then you probably want to look at getting an offset. If you can get the saddle set up to where everything feels balanced, for me that point is where I can ride with no hands, or nearly no pressure on my hands when sitting up straight and peddling. Make sure that your saddle is high enough (peddling backwards on heels seems to be a good indicator). At this point, at least for me, if your knees feel good you may have found the right spot for the saddle.

    The next step is figuring out the length of the stem and the height. For me I want to be able to have enough pressure on the front wheel without too much weight on my hands, at the same time I want to be able to get behind my seat on a descent. Basically be able to comfortably load and unload the front wheel and figuring that out usually has been some trial and error.

    Once I find what I think is the right setup I measure everything so I can replicate it. By measuring I put the bike against a wall on level ground and take a 4' bubble level and take measurements from a set point, usually where the seat rail attaches to the rear of the saddle or it can be just the back of the saddle. I'll then measure from the center of the crank horizontally and then on an angle to the seat. I'll measure the distance from the center of the bars to the same point on the saddle and the height of the bars.

    I've used this on a few hardtail bikes and it seems to work well and gets me close enough that only minor tweaks are needed, but your mileage may vary.

    John
    1995 Trek 970 - 80mm Atom Race
    1992 Serotta T-Max - 70mm Z3 Light
    1993 GT All Terra - 46mm Mag 21

  9. #9
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    Be careful with stem length, too much could be troublesome.

    Made the mistake of buying a bike the wrong size and tried to compensate by moving the seat back and handlebar forward. That seemed to work for but when I got into steep technical stuff will almost always be over the bars, that drove me nuts for a while until was able to make a frame swap for the right size and the problems went away. This may be or may not be your situation so experiment with cheap stuff until you find the sweet spot.

  10. #10
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    Seat position should be used to setup the relationship between the hips, knees and feet to the bottom bracket and pedals.
    It is not used for cockpit fit - or a least should be done before fitting the rest of the cockpit.
    You should probably start out with a KOPS setup and then fine tune from there.
    Take a look at:
    Learn How to Do a Basic Bike Fit - YouTube

  11. #11
    R.I.P. DogFriend
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    Quote Originally Posted by seryi View Post
    Hi.
    I know this has been discussed a lot but I couldnt find a clear answer to my specific situation. I bought a small Gt Karakoram like 3 weeks ago and everytime I ride it I feel like me and my *ss want to be seated farther back in order to be in a comfortable position (dont know if you get me). So to achieve this I should buy a longer stem or an offset seatpost? Maybe both to mantain some uniformity?

    Thank you in advance
    I'm inclined to start at the beginning here. How tall are you?

    You need to get on a properly sized bike, or you're going to be compromising handling and/or comfort in more situations than you would if you are riding a properly sized bike.

    A pic of the bike from the size would be nice too.

  12. #12
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    Thank you for all the responses.

    Im 5ft 7.5inch
    Inseam: 31.5inch/ 80cm
    Torso:25inch/ 63.5cm

    My KOPS is more or less right from what I could see by myself. The saddle height is right from what the guy in the LBS told (slightly bent knee when at the bottom position).
    My stem is 60mm - 10degree rise


    Offset sea vs longer stem-photo-5.jpgOffset sea vs longer stem-bike1.jpg

    Remember mine is Small

  13. #13
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    Is your saddle at level? Hard to see in the pic but to me you might be sliding forward while seated.

  14. #14
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    Dont know at that time but its at level now.

  15. #15
    I'd rather be on my bike
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    5'7.5" on a small? Seems like that might be an issue. I would imagine a medium at that height, just to start.
    '13 FELT TK3 48:15
    Fixed gear - but not a hipster
    2014 miles - 1088/2500

  16. #16
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    I bought a small Scott Spark 950. I am 5'8". I had the same problem and "fixed" it with a setback seatpost and a longer stem. The bike rides wonderfully... on the flat and slight inclines. Once I got steeper and more technical as my skills progressed, the more I had to fight the bike. I thought it was just my lack of skills until I bought a medium frame and went "Oh, this is what it is supposed to ride like."

    I now have a pair of slick tires on the Scott to make it easier to keep up with the girlfriend when she is on her road bike. It is terrible (read almost dangerous for me) on technical trails because it is too small, so now it is just a roadie.

  17. #17
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    The guys at the LBS told me Im at the edge of S/M frames and that this small fitted me well (I tried it but a few minutes in the parking lot wont tell you nothing). Maybe they just wanted to sell I dont know. And I got a good price on it. I saw some Specialized, Orbea, Giants, Trek too. All with lesser components/same price or equal/better components but more expensive. I thought "well Gt is supposed to be as good as the other brands plus better components and in most cases better price so the gt it is".

  18. #18
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    I'm 5'8" too; I agree that it's borderline small/medium.

    I still say, if you think an offset post might help, try it. Get the $15 one. It's already a lot better than the two-piece posts of the '70s and early '80s, and if you don't like it, you're only out $15. Kalin, maybe?
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  19. #19
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    I got a 25mm offset seatpost and it seems to solve the prob. Maybe Ill try a longer stem with the stock seatpost and see wich feels better.

  20. #20
    Fat-tired Roadie
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    You can probably get pretty close to your old position just by sliding your saddle all the way forward. Maybe not a great long-term solution, but it'll save you some trouble if you want to experiment with a longer stem and more forward hip position now.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

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