Are there any Bike Seat Bags that work with Suntour SP12 NCX Suspension Seatpost

[chopday]

Are bike seat bags not supposed to be installed if using a suspension post ?
I tried a few highly rated bags but none was a good fit on this post..the straps were not in the right place to secure the bag. I am using this suspension post along with A Cloud-9 seat on a Rad Expnd 5.

[JimInPT]

Are bike seat bags not supposed to be installed if using a suspension post ?
I tried a few highly rated bags but none was a good fit on this post..the straps were not in the right place to secure the bag. I am using this suspension post along with A Cloud-9 seat on a Rad Expnd 5.

I couldn't get mine working properly with my Redshift suspension post either - the movement of the mechanism messed with the bag's attachment straps. 

Here's a posting, with photo, of how I attached my tool bag to my MiniST2, strapped to my bike's frame/rack instead  - depending on which bike you have, something similar to this might work for you as well: 
https://www.radowners.com/index.php?topic=910.msg4854#msg4854

[chopday]

Thank you ..I will have to look into how you attached it ..and see if that works for me too.
What bag did you end up buying - asking esp. because the straps look different on your bag as compared to what I have seen..

[chopday]

I checked your post again and I actually tried the medium size of the bag instead of the large - https://amzn.to/3keCq20

Is it possible for you to explain or provide closer pics of how you adapted the straps to tie it down to the rad rack ?

[JimInPT]

Is it possible for you to explain or provide closer pics of how you adapted the straps to tie it down to the rad rack ?

Sure, I've attached some pics I just took; if these aren't clear enough let me know and I'll try for a reshoot.

It's a pretty simple arrangement, actually; the middle strap that normally goes above the bag into the seat frame to hang it from above, instead goes down and around the two black forward frame members of the rack.  The two straps that would normally wrap around the seatpost are instead wrapped around the two forward white frame members of the bike.  Very secure and out of the way of everything, yet accessible.  The stainless mini-carabiner is just there to hold the two zipper pulls together, nothing to do with the mounting. 

One thing I really like is that the bag-expansion section at the bottom really isn't needed for my stuff, but it's perfect to tuck in a pencil-style pressure gauge along the side, just under the zipper for that compartment, so it's accessible without having to mess with the bag mount or carabiner (that carabiner is a PITA to install/remove because it's so small, but I hope to only need to fiddle with it in emergencies).  This is the Large size of that bag, it tucks in nicely with the Mini's frame and rack as you can see and rests just above the rear fender - YMMV, depending on your bike model and rack. 

This arrangement isn't theft-proof, like any other underseat bag, but I arranged things to tuck the clips and velcro underneath and if my motion-sensitive alarm is set, it would be difficult to remove the bag without setting it off, even knowing the alarm is there (it's hidden).

Hope this helps; let me know if not.

[chopday]

Decided not to install a seat post bag ..probably will have to find another alternative to store my tools and other small items on the RadExpand.

[jastewart325]

I just installed the above-mentioned bag (large) on the Suntour seatpost without any problems; this is on a Rad City 5 Plus.

[chopday]

jastewart325 - Can you post a picture of your install ?

[Kari]

I have Topeak Aero Wedge Pack on my RadMini 4.

[chopday]

I have Topeak Aero Wedge Pack on my RadMini 4.

Thanks Kari for sharing the picture..I did not try the large size may be the straps on the large size are longer and will fit on a cloud-9 seat and the seat post as you have shown. My main problem when I tried was that I was not able to wrap the strap around the bag and thru the seat to get a secure fit - the straps were short.

[FL-GK]

I have Topeak Aero Wedge Pack on my RadMini 4.

Thanks Kari for sharing the picture..I did not try the large size may be the straps on the large size are longer and will fit on a cloud-9 seat and the seat post as you have shown. My main problem when I tried was that I was not able to wrap the strap around the bag and thru the seat to get a secure fit - the straps were short.

I always keep extra hook and loop straps from various bags etc. and I've got tons of it (so does everyone on this forum) I would think if it's as you describe using some scraps to lengthen the strap should do it. If you do not have any extra (yet) all the home improvement shops sell it.

[NaturallyRC]

The official RAD seat bag attaches perfectly to the Satori Harmony Road Mountain Bike Bicycle Suspension Seatpost on my Mini.

Are bike seat bags not supposed to be installed if using a suspension post ?
I tried a few highly rated bags but none was a good fit on this post..the straps were not in the right place to secure the bag. I am using this suspension post along with A Cloud-9 seat on a Rad Expnd 5.