KH adaptor for my new muni

My new nimbus 26" muni came a few days ago and i really hate the seat angle.

I bent the seat post on my trials by land wrong, and i striaghtened it but the plate thing on top is still bent (this is good), this means i can get alot more angle in my seat. So, after riding with and angled seat for a few months and going back to the flat seat i am dying.

Because i’m not the tallest person the seat on my muni has to be fairly low. The purpose of this thread was to make sure that a rail adaptor and head of a bike seat post will fit in about 3 inches.

How far below the edge of the seat do the rails hang (side view of seat how much of the rails do you see)?
And, will most bike seat post fit on the rails, are they the standard width?

this picture shows the amount for room i have for the adaptor (that hieght is i little too high)


PS. i couldn’t get the pic to work, sorry. It is about 3 inches.

There is PLENTY of room in 3" for a rail adaptor and seat post. The rails are standard width.

You have enough room, but you will have to choose your seatpost carefully.

Many seatposts are not designed to be clamped so close to the guts (the part of the seatpost that grips the seat rails). The diameter of the seatpost is not always held constant that close to the guts. The diameter of some (many?) seatposts increases slightly right below the guts where the guts are either welded or pressed in and bonded to the post. That means that with some seatposts you will not be able to insert them that far into the frame.

For example the Primo Rod style seatposts expand a little bit right below the weld due to the heat of the welding. I was using one on my Coker and ran into that problem when I tried 170 mm cranks. With the long cranks I needed to lower the seat as far as it would go and the Primo Rod seatpost I was using wouldn’t go down that far because the diameter of the post got bigger. I had to switch to a different seatpost.

An alloy seatpost that is machined all the way up the seatpost, like the Rockwerks, is more likely to let you insert it all the way into the uni frame. But even that is not guaranteed because the seatpost can still expand when the guts are pressed into and bonded in the post. So it’s something that you will have to check when buying the seatpost. Have the bike shop measure the seatpost with good calipers to make sure it is the right diameter right below the guts.