i’m having trouble keeping my ass glued to the seat when i’m riding fast… i’ve heard that’s normal when you pass your max rpm or something. is this true?
would lowering or raising my saddle help?
I don’t remember where I read it but that is an indication that your saddle is too high. Experiment with it a little until you find the right height.
Your seat is probably too high, so you are stretching your legs so far down that your hip is helping the pedal motion. You want your hips to stay out of this business, so yea, lower your seat.
Could be your seat is too high, could also be bad technique and inability to handle high RPM’s. Riding on rollers would likely remedy that if it’s the latter.
It’d be a seat height problem if your sprinting on flat and it happens, but if your spinning downhill it might just be your letting your legs go sloppy.
Hey man, change your avatar to your own custom frame so that I don’t have to be reminded of WMD’s hack job on that Guch every time you post.
i thought this was something you had to learn how to control
if my seat was any lower it wouldn’t feel right. my hips aren’t moving down or anything.
when it happens to me it usually means i have to flex my knees more
Flex your knees?
yea like i’m so focused on the down motion of the stroke that the up motion kicks my legs up. so i bend my knees and i guess spin the pedals instead of mashing on them and i stop bouncing in my seat and ride a lil better. great for the legs, too. i thought this was the whole “suppleness” or whatever people were talking about
nah, this is just how you’re supposed to ride a bike.
so riding my bike right is the solution? i dont really need to adjust the seat?
Concentrate on the up-stroke when you start bouncing. Pull up and it should help.
I was really expecting some kind of animated gif from this thread 
there ya go 
If your saddle was too high, your ass would bounce all the time, not just when you’re spinning fast, so it’s probably an issue of your pedaling form. I usually think about a motion that was first described to me as “scraping the shit off your shoe.” Basically, once you’re spinning that fast, it doesn’t take much force in the downstroke just to maintain speed, since gravity does that for you, but it helps to think about pushing a bit through the bottom of the stroke to help your leg make the transition from pushing down to moving up. I also try to keep my knees in as much as possible. I feel like that smooths out my pedaling quite a bit.
i thought this was something most people dealt with when they started riding fixed? i know it happened to me when i would go downhill and whatnot. basically, i just kept riding and it worked itself out.
some guy in front of me the other day was spinning and bouncing like a crazy idiot…i expected to easily catch up to him and i stopped really paying him any attention. next thing i see this guy is way ahead of me. i had to really try to keep up with him. i couldn’t comprehend why he would spin so fast, especially while bouncing around like he was. weird…
This is how a good spin was explained to me too. Once you start doing the wipe, you sorta realize the stroke you should be making and all the energy you’re wasting by not applying force in the correct direction. I find myself trying to make perfect circles when I pedal so I don’t throw away any energy. Imagine pushing a cart due east down some train tracks. Now imagine pushing the same cart, but you’re a dummy and you’re pushing it to the north-east. You’re only benefiting from the force moving the cart east, all your north energy goes nowhere.
Get a clipless saddle
