Suntour SP12 NCX 27.2mm Suspension Seatpost

I bought my Suntour seatpost from WalMart on line. It was $79 and included the dust cover. Had to order the heavier red spring directly from Suntour.
 
My curiosity got the best of me and I decided to give the Bodyfloat 2.0, $250, 350mm, double orange springs a try from Amazon since it has the 30-day return+additional 30-days to ship back once you start the return process. The main reason going with the Suntour was I can get two Suntours+two Cloud-9 seats cheaper than just one Bodyfloat. It was my B-day and I figured what the hell and ordered the Bodyfloat.

I'm still fine tuning the bodyfloat for comfort/control for work commuting and trail riding. I have the BodyFloat seatpost stem at its max height and I almost sent it back because it looked like it might be too short for me when set properly compared to my 400mm Suntour. The extra 1-1.5 inches of added thickness of my padded 11.5X12.5 Sunlite Cloud-9 seat does help with a little extra height for the BodyFloat for me compared to most regular bike seats. I think I would have to go with the extra length (and $140 extra cost above the $250 Bodyfloat price) of the 380mm carbon fiber BodyFloat if I had a thinner seat at my height and 34 inseam. I actually have the Bodyfloat about 3-4mm below the max height line trying to squeeze a touch more length out of it.

The BodyFloat and Suntour are about even on smooth paved roads/bike paths (as you would expect). I get a little more dips/float on the BodyFloat on larger bumps or undulating trails compared to the Suntour. Not enough to bother me and that could just require me to do more fine tuning on the BodyFloat to reduce the dip/float (currently have it set around 2-3 softer side on the 1-7 scale). The BodyFloat is far superior with much smaller bumps, ripples, washboard, and pockmarked trails in reducing the vibrations compared to the Suntour. Less vibrations are being transmitted to my backside; but, you know they are there because you can feel them in the pedals and handlebars. We have to share the trails with horses near the river and some parts can be riddled with pockmarks from the horseshoes; which, the BodyFloat can reduce a little more of the vibrations. I can see the BodyFloat being the better choice if you find yourself riding on a lot of broken pavement, uneven height sidewalk/paved road cracks, pockmarked/washboard/bumpy trails, and brick/cobblestone roadways.

My ebike front suspension, 4" wide 120 tpi Vee 8 fat tires set to 18-20 PSI, Sunlite Cloud-9 seat with spring adjustments, padded riding gloves, and padded riding shorts also contribute to the overall smoother commute/trail rides also with either the Suntour or BodyFloat. Your results may not feel the same with a different bike set-up.

The Suntour for my bike set-up and the way I ride is the 80%-85% solution compared to a fixed seatpost. I find the BodyFloat is able to get me to about 90%-95% in smoothing out the minor uneven surfaces the Suntour SP-12 just couldn't reach.

Another minor cons (along with the price) is the Bodyfloat seat height will lower as you dial in the amount of float you want. At level 1 (soft) down to level 7 (firm) can lower the seat almost an inch. My seat might be too low for my comfort if I decided to dial in the Bodyfloat between level 4-7 with my bike set-up and height.
 
This is my first post here. So hello everyone.

I know this is an old thread but hey they are all new to me. :)
MrGold, thanks for all of your advice in the conversion etc..

I just got my Rover two days ago. Finally got everything done on it.

Man the Rover is a much larger bike that I thought it would be. I LOVE it so far. I have only got to ride it briefly in my yard. The bike rack I ordered won't get here until next week so I can't take it out just yet. I don't live where I can just ride it around, I need to haul it someplace.

I ordered the Suntour 12 from Amazon but the listing was confusing. It said 31.6 OR 27.2 so I ended up with the 31.6 size. I thought it was a 27.2 with a removable sleeve. After my negative review I see now they list the 27.2. ;)

So I have to return it and am looking for the 27.2 size elsewhere as Amazon does not seem to have them at a decent price.

So my question is it seems the post that comes with the Rover is a 350mm. I am guessing here. I am also 6'3" and have the default post in about 4.5 inches. That is sitting pretty high. I have to jump up onto the seat a bit and my foot is at a tippy toe position to touch the ground. The seat goes higher than I thought it would.

So I assume the Suntour 350mm will do me fine? If that is the same as the default post I think it will. You are the same height so I am unsure how you have that 350mm maxed out as you mentioned.

Again if the default post is 350. I am unsure. Does anyone know what the length is on the default post?

I guess I just wonder, should I just get a 350mm or is the 400mm the better option? I am unsure if the 400 will cost more yet as I am still looking and the 350mm seems easier to get.

I am about 240 lbs, so I assume I should get the hard spring?
.
 
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I have both the 350mm and 400mm Suntour along with a 350mm v2.0 Bodyfloat with two orange springs (200-260 lbs) all with Sunlite Cloud-9 11.5X12.5 seats. I still had my old Radrover seat and seatpost. The 350mm works for me; BUT, I also have the much taller/thicker Cloud-9 seat (around 1.5 inches thicker than the RR seat).

I did a (very) rough measurement of max length:
21.65": 400mm Suntour + Sunlite seat
19.5" : 350mm Suntour + Sunlite seat
19.25": BodyFloat + Sunlite seat (seat will drop around 1/2" once I put my weight on it)
17.5" : Radrover standard seat + 350mm seatpost

I can use the 350mm Suntour+Sunlite and I'm at the max height line (even a 1-2mm over for added comfort). That was the reason I wanted the 400mm Suntour because I was so close to the line and I do sometimes have to adjust the seatpost a tiny bit at times. I changed out the crank pedals (Wide Platform MTB BC Pedals for my size 14 shoes), I wear thicker Hi-Tec hiking boots when riding in winter compared to thinner running shoes in summer, layered cold weather gear in winter, and sometimes were padded shorts. I needed to adjust the seatpost a little above the max line sometimes with the 350mm.

Top to bottom:
RR seat + 350mm seatpost
Cloud-9 + BodyFloat 350mm seatpost
Cloud-9 + Suntour 350mm seatpost (gray spring, don't know if it is firm, soft, or somewhere in-between)
Cloud-9 + Suntour 400mm seatpost (gray spring, don't know if it is firm, soft, or somewhere in-between)

NOTE: The gray colored spring works for me at +270lbs at my max commuter riding weight.


(Link Removed - No Longer Exists)
 
As far as the Suntour springs go at my 270 lbs the gray spring the seat just bottomed out sitting on the bike. I went to the red spring and after a couple of extra turns in the adjustment it works fine with the Cloud 9 seat. I have the 350mm Suntour. I am sure my riding weight is probably closer to 280 lbs with gear.
 
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mrgold35 said:
I have both the 350mm and 400mm Suntour along with a 350mm v2.0 Bodyfloat with two orange springs (200-260 lbs) all with Sunlite Cloud-9 11.5X12.5 seats. I still had my old Radrover seat and seatpost. The 350mm works for me; BUT, I also have the much taller/thicker Cloud-9 seat (around 1.5 inches thicker than the RR seat).

I did a (very) rough measurement of max length:
21.65": 400mm Suntour + Sunlite seat
19.5" : 350mm Suntour + Sunlite seat
19.25": BodyFloat + Sunlite seat (seat will drop around 1/2" once I put my weight on it)
17.5" : Radrover standard seat + 350mm seatpost

I can use the 350mm Suntour+Sunlite and I'm at the max height line (even a 1-2mm over for added comfort). That was the reason I wanted the 400mm Suntour because I was so close to the line and I do sometimes have to adjust the seatpost a tiny bit at times. I changed out the crank pedals (Wide Platform MTB BC Pedals for my size 14 shoes), I wear thicker Hi-Tec hiking boots when riding in winter compared to thinner running shoes in summer, layered cold weather gear in winter, and sometimes were padded shorts. I needed to adjust the seatpost a little above the max line sometimes with the 350mm.

Top to bottom:
RR seat + 350mm seatpost
Cloud-9 + BodyFloat 350mm seatpost
Cloud-9 + Suntour 350mm seatpost (gray spring, don't know if it is firm, soft, or somewhere in-between)
Cloud-9 + Suntour 400mm seatpost (gray spring, don't know if it is firm, soft, or somewhere in-between)

NOTE: The gray colored spring works for me at +270lbs at my max commuter riding weight.


(Link Removed - No Longer Exists)
Click to expand...
Since you have both the 350 and 400mm Suntour, can you do me a favor and measure them from the bottom to the top of the rails, and then also from the min insertion line to again the top of the rails where you will mount the seat? Thank you.
 
AZOldTech said:
Since you have both the 350 and 400mm Suntour, can you do me a favor and measure them from the bottom to the top of the rails, and then also from the min insertion line to again the top of the rails where you will mount the seat? Thank you.
Click to expand...

Will do this weekend
 
I took some rough measurements from the minimal insertion line to the where the seat attaches to the Suntour seat rails. It was a little hard to measure exactly because the seat rails are at a slight angle for the seat to be level to the ground. I "guess-i-mated" and used the center part of the seat rail near the Suntour pivot point as a mark. The red line is from my stud finder with laser leveler (my iphone was a little off center with the pic of both Suntours):

350mm Suntour from rail to min: 11.5 inches
400mm Suntour from rail to min: 13.5 inches
50mm = 1.97 inches


I didn't notice I ended up using the same picture for the 350mm and 400mm measurement from my original post. I updated the post with the 350mm pic.
400mm Suntour.jpgBoth Suntours.jpg350mm Suntour.jpg
 
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mrgold35 said:
I took some rough measurements from the minimal insertion line to the where the seat attaches to the Suntour seat rails. It was a little hard to measure exactly because the seat rails are at a slight angle for the seat to be level to the ground. I "guess-i-mated" and used the center part of the seat rail near the Suntour pivot point as a mark. The red line is from my stud finder with laser leveler (my iphone was a little off center with the pic of both Suntours):

350mm Suntour from rail to min: 11.5 inches
400mm Suntour from rail to min: 13.5 inches
50mm = 1.97 inches

(Link Removed - Attachment No Longer Exists)View attachment 30636View attachment 30637
Click to expand...
Many thanks @mrgold35
 
I just got a Suntour SP12 NCX seat post for my Stromer ST2. It feels good (even better than the Satori Animaris suspension seat post). My only complaint is that the adjustment instructions in the manual are TERRIBLE! How do I know if it's "1/3 compressed" while I sit on it (without moving) even if someone else is helping?

Does this mean the seat post should be compressed all the time? Any tips on adjusting the thing properly?
 
Dabido said:
I just got a Suntour SP12 NCX seat post for my Stromer ST2. It feels good (even better than the Satori Animaris suspension seat post). My only complaint is that the adjustment instructions in the manual are TERRIBLE! How do I know if it's "1/3 compressed" while I sit on it (without moving) even if someone else is helping?

Does this mean the seat post should be compressed all the time? Any tips on adjusting the thing properly?
Click to expand...

That is preload adjustment. Means when you put your weight on it, it should compress round 1/3". If it compresses more it will bottom out on holes, deep cracks etc. if it compresses less it will be too stiff and will not absorb the bumps as much. I would put my bicycle next to a wall and put a mark on the wall that is on level with the tip of the saddle when you are on and off of the bike.

How much do you weight btw?

I haven't tried ncx but I have been using animaris for a long time and it is an excellent suspension, again you need to do the preload adjustment to your weight before you can assess how well it works for you.
 
Johnny said:
That is preload adjustment. Means when you put your weight on it, it should compress round 1/3". If it compresses more it will bottom out on holes, deep cracks etc. if it compresses less it will be too stiff and will not absorb the bumps as much. I would put my bicycle next to a wall and put a mark on the wall that is on level with the tip of the saddle when you are on and off of the bike.

How much do you weight btw?

I haven't tried ncx but I have been using animaris for a long time and it is an excellent suspension, again you need to do the preload adjustment to your weight before you can assess how well it works for you.
Click to expand...


Ahhh, 1/3" actually makes more sense than 1/3 of the total travel. If that's the case, the seatpost should compress slightly - and stay that way - whenever I sit on the bike, correct?

The manual does not state anything about measurement units. The entirety of the adjustment instructions are:

"1. Check the adjustment:
With somebody’s support, sit on the bike with your hands and feet positioned normally. Have
the supporter looking and confirm that the seatpost is approximately 1/3 compressed.
  1. If the compression is not within the range as explained above, remove the seatpost from the
    bicycle frame.
  2. To increase the preload, with a 6 mm Allen key, turn the adjuster clockwise. To decrease the
    preload, turn the adjuster counter-clockwise, taking care to leave a minimum 10mm of exposed threads visible at the bottom of the seatpost."

I weight about 185 lbs. and ride pretty fast (avg. 20+ mph) on pot-holed, bumpy roads in Salt Lake City, so smooth suspension is not only more comfortable but gives me more control.
 
Dabido said:
Ahhh, 1/3" actually makes more sense than 1/3 of the total travel. If that's the case, the seatpost should compress slightly - and stay that way - whenever I sit on the bike, correct?

The manual does not state anything about measurement units. The entirety of the adjustment instructions are:

"1. Check the adjustment:
With somebody’s support, sit on the bike with your hands and feet positioned normally. Have
the supporter looking and confirm that the seatpost is approximately 1/3 compressed.
  1. If the compression is not within the range as explained above, remove the seatpost from the
    bicycle frame.
  2. To increase the preload, with a 6 mm Allen key, turn the adjuster clockwise. To decrease the
    preload, turn the adjuster counter-clockwise, taking care to leave a minimum 10mm of exposed threads visible at the bottom of the seatpost."

I weight about 185 lbs. and ride pretty fast (avg. 20+ mph) on pot-holed, bumpy roads in Salt Lake City, so smooth suspension is not only more comfortable but gives me more control.
Click to expand...

:) so you need a "supporter". Yes the seatpost should compress slightly - and stay that way - whenever you sit on the bike until you start moving and going over potholes when it compresses more.
I am also not 100 sure about the units, I think you can find the maximum travel of NCX (I read that it is around 2" somewhere). So you can try 1/3" and 2/3" and see whichever you like most.
If you have serious potholes just make sure that it is not so soft that it bottoms out at higher speeds that is usually my main concern. For small regular unevenness decreasing the tire pressure usually makes a significant difference.

Btw how are you liking your st2 so far?
 
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Johnny said:
:) so you need a "supporter". I am also not 100 sure, I think you can find the maximum travel of NCX (I read that it is around 2" somewhere). So you can try 1/3" and 2/3" and see whichever you like most.
If you have serious potholes just make sure that it is not so soft that it bottoms out at higher speeds that is usually my main concern. For small regular unevenness decreasing the tire pressure usually makes a significant difference.

Btw how are you liking your st2 so far?
Click to expand...


I bought a secondhand 2017 ST2s back in January, and it's awesome! It's so fun to ride I've regularly been out in sub-freezing temperatures in northern Utah. I like it even more now that coronavirus is making public transportation less appealing.

My only complaint is that it took a month of hassle to get the bike registered with Stromer and fully connected to the interwebs and the Stromer app, which is necessary to use Stromer tech like the anti-theft system and custom motor tuning. To be fair, some of the difficulties stemmed from timing. I bought the bike just after U.S. cellular carriers decommissioned the 2G cellular network, which meant the original OMNI GPS/cellular unit in the bike lost all connectivity. Upgrading to the newer 3G OMNI-C unit was not cheap (about $350) and took several trips to the local bike shop and numerous email exchanges with Stromer USA to get it 100% functional.

150 miles in, though, all is well, and the advent of bike season (almost) makes up for the abrupt and untimely end of this year's ski season!
 
i just bought the suntour seatpost the ncx 31.6 for my stromer st1 platinum and i ride both of road and mtl downtown daily- if you’ve ridden you could call it concrete jungle riding. the roasts are a joke. and i messed up back from hockey. spasms. slipped/bulged& pinched nerve+ nerve damage. lol so glad it at least paid for some of my life but not worth the cte- anyway as i was asking; will this do anything for back pain- even if it’s a little bit. and i have the carbon fork. not the spring/suspension- oh and ulock is an amazing piece of work. to anyone who rides enough to be ok spending 70-80$ on a phone holder/display. and no i went thru 5 other pieces of money them at equaled enough to make me happy with spending that much
 

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