Hello,

I got a used bike a couple months ago and am still trying to adjust it to fit just right. It's the proper frame size for me (56 cm top tube and I'm 5'10") but it's an old mountain bike frame converted into a touring set up so I imagine the geometry is different (for example it has a shorter seat post and standover height than a 56 cm road bike). I feel like I'm sliding forward in my seat a bit and can't figure out why. I have it maybe 90% of the way back on the rails to work for the KOPS method of saddle fore/aft and have the seat level. I'm wondering if maybe the shape of the seat has something to do with it as it is not flat. Any ideas? I'm really considering just going for a bike fit but I'm so close to getting it right and I mainly commute and maybe every week or two do a 20 km ride.

KOPS is a starting point not the end state. Your riding style, flexibility and center of gravity all determine optimal seat fore/aft position. Your riding style may be telling you your seat should go forward, it could also be the reach is too long for you, etc. Impossible to diagnose without you getting fit.

If that post isn't infinitely adjustable, i.e. a 2-bolt adjustment, getting a post which is might be a good start. Very small saddle tilt adjustments make a big difference. Looks like a post with more set-back would be a good idea, too. Velo Orange makes some, others also. Issue might be that you'll need a longer than usual post.

Do your hands feel light on the bars?

Ya I think I could be helped with a slight tilt. When the seat tilts it can only click into set angles and the first click is angled way too far up. My hands feel fairly light at the beginning of my ride but after maybe 10 minutes I find myself placing more weight on them. I feel like if I don't consciously think about keeping my hands light I put too much weight on them.

If you are sliding forward, and as it appears, your saddle is level. it may be a bit further forward is where you need to be. Since it does not cost anything to slide the saddle forward, go ahead and try a cm adjustment. Mark the rails somehow so that if the change does not work out, you can get back to the old position.

What I would do (YMMV) is tilt the saddle back ever so slightly, so that your hips are firmly planted on the seat and not sliding forward constantly. I think having them anchored is important. Might make riding in the drops less than ideal, but it's what i would do, FWIW.

Also, I have done a couple MTB to drop bar conversions, and found it impossible to get comfortable on them. Thought it would be a cinch, but it was anything but, and finally gave up.

You could simply switch to a flat saddle with a similar size and shape.

Check seat height too. Your seat may be a bit too high. Excessive reach may also be a factor, you may want to try a shorter stem.

For seat height, try this method: https://www.stevehoggbikefitting.com...ard-can-it-be/ There is also information on setting seat setback on his site that you may want to look at.