What's NOT said about Suntour NCX seatpost

Avg_Joe

Well-Known Member
Region
USA
City
RDU, NC
I've had the Suntour NCX seatpost on my Rover StepThrough for a few hundred miles now, and have been fidgeting with my riding position. Today I had an epiphany: The seat offset on the NCX seatpost is pretty extreme when compared to others - the seatclamp is at least 1.5" or more rearward vs the factory rigid post. This was not something I was aware of when I bought it due to my own ignorance/newness to bikes and components.

I have been experiencing some post-ride discomfort in my wrists, elbows, and hips. While riding today, I realized how far behind the crank centerline my hips were. Even with my seat adjusted forward to the limit, I'm really reaching for the grips and hunched over; and it's almost like I'm push-pedaling if that makes sense. I'm not looking for a cruiser position, a quasi-"athletic" position works well for me. But this is rather extreme.

I'm putting my rigid post back on tonight and will see if this discomfort subsides. I am also looking at suspension seatposts with 0 offset, not interested in the $200 posts as I want just moderate suspension (I run my Innova 26x4's at 16 psi which helps a bit) and no need for the parallelogram/elastomer design - a simple spring is plenty for me.
 
Rather than refitting the stock seatpost, I disassembled the SCX post, flipped the top around, cleaned and lightly greased, and now the seat is close to 0 offset from the tube. Problem solved.
 
I sold my Suntour seat post for the same reason. I was unable to adjust it back enough for a good fit. I tried to return it but the manufacturer refused saying it was used. Only tried it and quickly removed it once I realized it did not work for me. Sold it in EBay at a loss.
 
I sold my Suntour seat post for the same reason. I was unable to adjust it back enough for a good fit. I tried to return it but the manufacturer refused saying it was used. Only tried it and quickly removed it once I realized it did not work for me. Sold it in EBay at a loss.
Weird. I ordered mind from a German site and added replacement springs. My correct spring and one lower weight spring. All good. For me the best seat post. Much better than those using rubber like blocks. And 20% less than USA sources, even with shipping from DE.
 
Rather than refitting the stock seatpost, I disassembled the SCX post, flipped the top around, cleaned and lightly greased, and now the seat is close to 0 offset from the tube. Problem solved.
So your saying you flipped the seat around on the NCX so it compresses toward the handle bars? And this works okay?
 
So your saying you flipped the seat around on the NCX so it compresses toward the handle bars? And this works okay?
Yeah I was wondering the same thing. Doesn't sound possible thats a good thing.

Bicycle fitment is something you can fiddle with to a bigger extent than many may realize. Its something I am covering in my 'how to build an ebike from scratch' series. Here's a picture from the 'Perfecting' chapter that I have yet to release. If your saddle is too far back because of seatpost setback, then rather than chucking your post your next fitment alternative (after moving the saddle forward to the furthest extent allowed on the scale found on the side of the seat rails) is to put in a shorter front stem - assuming thats possible. This brings your handlebars back towards you after you moved your body back and increased your reach with the seatpost. A shorter stem also makes steering more responsive, which is probably something you will not notice, frankly.

The OP's discomfort is, I think, much more likely due to reach than it is to leg position.

PXL_20220406_024131101.jpg


I started out with a 110mm post with a 7-degree rise (not pictured) and ended up changing to the far-right stem, which is a 120mm stem with a 45mm rise, taking my bars further out and up (I had a different issue to solve that mostly involved handlebar height).

Now I have to literally think about laying my hands flat on the bars on this bike. My gut tells me to grab the bars with thumb and forefinger and ried that way which tells me I may have solved the height problem, but now I need to deal with reach. A hopefully final solution on this bike will be to add in a PNW Components Coast suspension dropper post (note the use of those two terms - suspension dropper - in the same sentence). That post has a zero setback versus the probably 1 inch setback I have now, and advertises 40mm of travel but reality is its much more if you ride with the post normally extended.
 
This was not something I was aware of when I bought it due to my own ignorance/newness to bikes and components.

And there you have it...

The post does state that it flexes rearward which is correct and how it should be. Your seat should also allow you to slide it forward so if it has short bars it's really a compatibility issue with your seat.
The one and only issue that I had with the post is that I feel that the springs are over_rated... Meaning for my weight I should be able to use the stock Medium but found that the Soft spring works better for me though I'm 20lbs over its suggested range.
 
So your saying you flipped the seat around on the NCX so it compresses toward the handle bars? And this works okay?
Absolutely not. What I did is remove the 4 set screws which hold the roller pins in place and pushed out the pins; reassembled the lower part as per how it came (had to remove this lower roller pins to get to the upper set screws); then flipped the top part + seat mount around so the seat mount is almost inline with the post. It works the same as it came when new, it's just the seat mount is about 1.5" more forward, and higher, which allowed me to drop the post further down into the tube.

Hopefully this picture helps show how the seat mount is more forward and higher than the original position:
1652050637867.png

The stock location from Suntour has the seat mount back much further and lower.
 
And there you have it...

The post does state that it flexes rearward which is correct and how it should be. Your seat should also allow you to slide it forward so if it has short bars it's really a compatibility issue with your seat.
The one and only issue that I had with the post is that I feel that the springs are over_rated... Meaning for my weight I should be able to use the stock Medium but found that the Soft spring works better for me though I'm 20lbs over its suggested range.
 
I'm wondering if maybe I have the same issue. Because if my weight, I purchased and installed the "heavy" red spring (while removing the standard black one) before I rode with the new seatpost on and it seemed to be pretty hard. Maybe I'll do a lap around a gravel track that I normally use with the red one and then swap it out with the standard black one and do another lap for comparison.
 
Corkster52
I'm wondering if maybe I have the same issue. Because if my weight, I purchased and installed the "heavy" red spring (while removing the standard black one) before I rode with the new seatpost on and it seemed to be pretty hard. Maybe I'll do a lap around a gravel track that I normally use with the red one and then swap it out with the standard black one and do another lap for comparison.
Well you have the spring it wouldn't hurt to try
 
Absolutely not. What I did is remove the 4 set screws which hold the roller pins in place and pushed out the pins; reassembled the lower part as per how it came (had to remove this lower roller pins to get to the upper set screws); then flipped the top part + seat mount around so the seat mount is almost inline with the post. It works the same as it came when new, it's just the seat mount is about 1.5" more forward, and higher, which allowed me to drop the post further down into the tube.

Hopefully this picture helps show how the seat mount is more forward and higher than the original position:
View attachment 122763
The stock location from Suntour has the seat mount back much further and lower.
Great info Avg_Joe
I'm currently experimenting with my new Suntour NCX suspension seat post, and have a Brooks B17 saddle on the way, so could be using your seat mount reversal mod.

Couple of questions for you, or anyone else that wants to chime in.

With the mount reversed as per your pic, would that decrease the leverage of the riders weight against the spring ?
If so, doing that mod could also require a softer spring for some riders ?

The coarse pitch of the NCX seat clamp teeth dont allow for fine adjustment, however with the stock location of the seat clamp, the seat can be set to sit level.
Can a level seat mounting still be achieved when the seat mount is reversed ?
 
Great info Avg_Joe
I'm currently experimenting with my new Suntour NCX suspension seat post, and have a Brooks B17 saddle on the way, so could be using your seat mount reversal mod.

Couple of questions for you, or anyone else that wants to chime in.

With the mount reversed as per your pic, would that decrease the leverage of the riders weight against the spring ?
If so, doing that mod could also require a softer spring for some riders ?

The coarse pitch of the NCX seat clamp teeth dont allow for fine adjustment, however with the stock location of the seat clamp, the seat can be set to sit level.
Can a level seat mounting still be achieved when the seat mount is reversed ?
Hi @bill_1960 I did find that in reversing the mount, it "seemed" stiffer - or less leverage; so I ratcheted down the preload. Keep in mind I'm no pro, just going by how it felt to me. I do believe the lighter spring would be a great experiment. FWIW I'm not riding my Rad any longer and my wife doesn't care for it, so I've not pursued a spring change.

I had no trouble whatsoever getting the seat level.
 
Hi @bill_1960 I did find that in reversing the mount, it "seemed" stiffer - or less leverage; so I ratcheted down the preload. Keep in mind I'm no pro, just going by how it felt to me. I do believe the lighter spring would be a great experiment. FWIW I'm not riding my Rad any longer and my wife doesn't care for it, so I've not pursued a spring change.

I had no trouble whatsoever getting the seat level.
Thanks for the reply @Avg_Joe

I reversed the seat mount and couldnt really tell if the spring felt stiffer or not.

Took a few pics for those interested.

For the sag adjustment, the manual recommends 1/3 of travel. Full length of the exposed suspension rod is 24.25mm, less around 3mm for the wear disc on top. Therefore 1/3 travel is roughly 7mm.
IMG20220804093119.jpg


I placed an Oring over the rod to help measure the sag when I sit on the bike.
IMG20220804094821.jpg


After pushing the O ring to the bottom, then sitting on the bike, I was able to measure how much the O ring moved. In the following pic, thats around 7mm of movement. The bottom spring adjuster has around 12mm of threads exposed (minimum 10mm recommended) so it should be all good.
IMG20220804100416.jpg


I weigh 70kg. According to the manual, the standard spring is for 70-95kg rider, soft spring for up to 75kg rider, so I've ordered the soft spring and will compare.
 
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Thanks for the reply @Avg_Joe

I reversed the seat mount and couldnt really tell if the spring felt stiffer or not.

Took a few pics for those interested.

For the sag adjustment, the manual recommends 1/3 of travel. Full length of the exposed suspension rod is 24.25mm, less around 3mm for the wear disc on top. Therefore 1/3 travel is roughly 7mm.
View attachment 131122

I placed an Oring over the rod to help measure the sag when I sit on the bike.
View attachment 131123

After pushing the O ring to the bottom, then sitting on the bike, I was able to measure how much the O ring moved. In the following pic, thats around 7mm of movement. The bottom spring adjuster has around 12mm of threads exposed (minimum 10mm recommended) so it should be all good.
View attachment 131124

I weigh 70kg. According to the manual, the standard spring is for 70-95kg rider, soft spring for up to 75kg rider, so I've ordered the soft spring and will compare.
I think you will appreciate the Soft spring.
 
In the process of setting up a new bike with new NCX seat post, and just wanted to share that after flipping that top bracket 180 degrees, I found myself too far forward without enough real estate ahead of me. Post functioned perfectly.

Point being, flipping that top bracket is not going to work out for everyone - though I can certainly see the logic behind the idea!! Noteworthy is the fact there are not many guys my size riding bikes (6'1"/315)
 
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