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I was recently "fitted" to a custom road frame, and find that it fits quite nicely. The fitter used the KOPS method of seat/ fore/aft placement. Thus assuming that with the knee over pedal, my seatpost would be in the center of the saddle...I could move it back or forward and still be "balanced". I seem to be comfortable with the knee directly over the pedal.
If I use this method with my HH100, I would have the seat ALL the way forward...using all the rail. So, it appears that this may not be translated to mountain biking. In your experiences, how far behind the "pedal" do you like to see your knees? The way I measure is: I put a 4' level vertical, cutting the center of the BB....then I measure the distance from that center point to the tip of my saddle. If my road bike is (let's say) 1.75", the mtb seems to be about 3"....
If I am getting too neurotic, tell me...but I want to tranfer as much POWER to the pedal as possible... and I'll bet that seat placement governs that.
Got any ideas?
 

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Vaginatarian
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do what ever is more comfortable, if you're riding single track you're moving all around on and off your seat anyway, height makes a diff. too (more power higher, more flexability lower)
 

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It's about showing up.
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MTB is not road

nor are road bikes of the same geometry as mtb. I think it takes more experience from the rider to fit an mtb because the rider has to know where she is in relation to the pedals for all the different kinds of riding she does.
You may find that, over time, you move your road seat, too. KOPS is just a place to start.
 

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I agree with the other posters....

seat placement is as personal as underwear. The primary governing factor for an MTB is usually comfort, more than performance. For most riders it is not that big of a deal. If you are racing then getting every erg of energy to the pedals is important. But there are allot of riders out there that just don't race. Anyway as was mentioned KOP is a starting point only and is not designed to be the do all and end all of bike fit. It is designed to get you very close to where you need to be. It is always recommended, or should be, that fine tuning be done as you ride and notice that changes need to be made.

The factors that I use to determine where my saddle needs to be are my back, my knees and my butt, or other parts closely related there to. :D For me anyway, being comfortable is directly related to how much power I can lay down. I find that having the saddle to high or too low will cause pain in my knees while riding. And I find that if my saddle is to far foward I will experience pain in my lower back and hips, and a saddle that is to far back will cause numbness in the "related areas" shall we say. Anyway, on my bikes I have found that the nose of my saddle is usually right around 2 1/4" behind the center line of my bottom bracket. This is variable depending on the geometry of the bike of course. But I usually use this measurement as a starting point. And will fine tune from there. But I've never had a bike that was much more than 1/4" plus or minus from that figure. I don't have a road bike, but hope to soon. I am sure that the set up for that will be different as the geometry is different.

The bottom line is that the KOP system works well as a starting point for road bike fit, but the geometry is enough different between road bikes and MTB that it probably doesn't translate that well for most riders. As I stated earlier, bike fit is as personal as preference in underwear. All of that being said, KOP can be used for initial MTB set up, but be prepared to make significant changes if needed. And most important, pay attention to what your body tells you about the fit of the bike. Discomfort anywhere usually indicates that a change is required somewhere. So go ahead and use the KOP for your initial set up,, but keep in mind that it is just that, INITIAL set up. Fine tuning will end up being done by the seat of your pants, literally! :D Just my 2 cents.

Good Dirt
 

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i ride xc; steep climbs/descents, single track, fireroads. i use the entire saddle; sit on the nose for climbing and sprinting, sit on the rear edge with my thighs clamping (or just nudging) the nose on decents. as long as the saddle is placed central for the varied positions i need, it's good. angle is so the nose doesnt dig into my crotch, height is so that i can put both toes on the ground. i also like a frame size where the saddle is 5-6 inches above the top tube. cockpit is then adjust by stem length with preferably a longer stem (120mm) for roominess, stable (not twitchy) handling and ample forward weight balance. i dont use antlers, but using them could let you get away with a shorter stem for more rearward weight balance on descents.
 

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www.derbyrims.com
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laidback seat post? sag?

Alan said:
I was recently "fitted" to a custom road frame, and find that it fits quite nicely. The fitter used the KOPS method of seat/ fore/aft placement. Thus assuming that with the knee over pedal, my seatpost would be in the center of the saddle...I could move it back or forward and still be "balanced". I seem to be comfortable with the knee directly over the pedal.
If I use this method with my HH100, I would have the seat ALL the way forward...using all the rail. So, it appears that this may not be translated to mountain biking. In your experiences, how far behind the "pedal" do you like to see your knees? The way I measure is: I put a 4' level vertical, cutting the center of the BB....then I measure the distance from that center point to the tip of my saddle. If my road bike is (let's say) 1.75", the mtb seems to be about 3"....
If I am getting too neurotic, tell me...but I want to tranfer as much POWER to the pedal as possible... and I'll bet that seat placement governs that.
Got any ideas?
Most mountain bikes come with a seat post with seat rail clamps centered 1 to 1.5 inch laid back behind the center of the seat tube. And to get a proper race or climbing position you do need to position your seat far forward on the rails using these commonly speced laid back seat posts.

Also check that your fork sag on the HH is as much if not a little more than your rear travel sag (the rear has a shorter travel range). Sag makes a big difference in your position over the pedals.

A more laid back seated position lowers the rider weight without shortening leg reach and is more forgiving downhill for braking confidence and easier handling in very rough and irregular terrain when going up, down, or flat. But it is less energy efficient when climbing.

Mountain biking is much more varied in environment than road, and tradeoffs in efficiency are made for the extremes in handling often encountered.

If you find that you like the more forward on the rails seat position using a commonly speced laid back post, get a quality centered clamp seatpost such as a Thompson. If the HH100 has the same seat tube angle as the standard RacerX (I'm not sure) it should fit pretty well near the middle of the seat rails for climbing with a center clamped post.

- ray
 

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dan0 said:
do what ever is more comfortable, if you're riding single track you're moving all around on and off your seat anyway, height makes a diff. too (more power higher, more flexability lower)
yep....do what ever is more comfortable
 

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I make sure that my knee cap does not pass big toe at the top of the pedal stroke(plum line to check). I make adjustments from there. I read that in a bike magazine. Long ago in college, I was taught, when you squat in the weight room, good form is when your knee caps do not pass your big toe. It makes sense, since cycling is a similar movement. Granted, dependent on your frame geometry that it might not be valid, but for me it's a good starting point.
 

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Alan said:
I was recently "fitted" to a custom road frame, and find that it fits quite nicely. The fitter used the KOPS method of seat/ fore/aft placement. Thus assuming that with the knee over pedal, my seatpost would be in the center of the saddle...I could move it back or forward and still be "balanced". I seem to be comfortable with the knee directly over the pedal.
If I use this method with my HH100, I would have the seat ALL the way forward...using all the rail. So, it appears that this may not be translated to mountain biking. In your experiences, how far behind the "pedal" do you like to see your knees? The way I measure is: I put a 4' level vertical, cutting the center of the BB....then I measure the distance from that center point to the tip of my saddle. If my road bike is (let's say) 1.75", the mtb seems to be about 3"....
If I am getting too neurotic, tell me...but I want to tranfer as much POWER to the pedal as possible... and I'll bet that seat placement governs that.
Got any ideas?
Like others have said, road is different than MTB, and among MTB it varies widely. Road is all about power to the wheels, whereas MTB throws in very steep climbs, very steep decents, things to drop and jump off, obsticals to clear, and VERY unpredictable traction.

I do have my knee over my pedal on my road bike at it feels perfect, but on my ss HT it is a little behind the pedal, and on my trail bike it is way behind the pedal. I have tried sliding it forward, but it makes the bike hard to lean in turns (and still have some clearance for bumps), get behind the saddle, and in general throw the bike around. Sliding it back gives me more room to move around.
 
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