Seat post adaptor

[cwah]

Hello

I ordered a banana seat in order to carry passengers on my bike:
https://www.dropbox.com/s/71yase4wxru3udn/IMG_20180505_125809.jpg?dl=0

However, the seat has this:
https://www.dropbox.com/s/9j1p41ipwjyogem/IMG_20180505_140551.jpg?dl=0

And my seat use a rail:
https://www.dropbox.com/s/iekqohhck5mv6i2/MVIMG_20180505_140638.jpg?dl=0

Where can I find an adaptor to fit to my seat tube?

Thanks

 

[mike killay]

You need to get a new seat post.
I had the same problem.
Equally, if you remove the collar attachment from the new seat, you might be able to fit the seat post already on your bike

 

[chris_n]

https://www.jejamescycles.com/raleigh-standard-steel-seatpost.html?gclid=EAIaIQobChMIqKXCi-Du2gIVxLTtCh2R2QyIEAQYAiABEgLkwvD_BwE

 

[Deleted member 4366]

You need a tapered seat-pin, like this, but you have to get one the same diameter as what you already have or use shims if yours is bigger.

https://www.ebay.co.uk/itm/STRONG-ALLOY-SEAT-PIN-29-4mm-DIAMETER-300mm-LONG-HANDY-RARE-SPARE/263643714909?hash=item3d6263d55d:g:Q8kAAOSwjIVac2YC

 

[cwah]

You need a tapered seat-pin, like this, but you have to get one the same diameter as what you already have or use shims if yours is bigger.

https://www.ebay.co.uk/itm/STRONG-ALLOY-SEAT-PIN-29-4mm-DIAMETER-300mm-LONG-HANDY-RARE-SPARE/263643714909?hash=item3d6263d55d:g:Q8kAAOSwjIVac2YC

These are the dimensions:
https://www.dropbox.com/s/ds8zuksl61ln8n4/MVIMG_20180505_175652.jpg?dl=0

https://www.dropbox.com/s/e79dyce7x9z1hn6/MVIMG_20180505_175736.jpg?dl=0

Which one do I need?

 

[mike killay]

CWAH,
It is not the diameter of the collar that you measure but the diameter of the existing seat post.
Chances are that it is already marked on it, take it out and look. Other wise, measure it.
The top part of the post will be smaller and the collar is adjustable and will tighten around it.

 

[cwah]

I measured both just in case
https://www.dropbox.com/s/hlgtu9waspnoiu9/MVIMG_20180505_194053.jpg?dl=0

https://www.dropbox.com/s/5s6vj72qlba8690/MVIMG_20180505_194043.jpg?dl=0

 

[mike killay]

No, not the hole, the post itself.

 

[mike killay]

This what you measure. This one is marked 27.2mm

 

[cwah]

View attachment 24602 This what you measure. This one is marked 27.2mm

So I got this
https://www.dropbox.com/s/lxlwcd5qq9qb6e4/MVIMG_20180505_201501.jpg?dl=0

I need 26,8mm seat tube?

 

[mike killay]

Is the post marked with its size?
You might have trouble finding a tapered seat post of 26.8.
Best wait until someone else replies, it might be possible to get a smaller one and use shims.