Did that today with my Mitutoyo's. It's a carbon seatpost and the numbers were all over the place. Went from 31.4 to 31.7 depending on where I took the reading! Oh what fun. Too lazy to pull the post and measure the ID of the tube. Since I haven't seen a seat post offered in a 31.8 I guess it really doesn't matter at the end of the day anyway. I've only had the bike for 24 hours so I guess I'm better off just riding it at this point. It's supposed to be fun, why ruin it!@opimax, please feel free to disagree with me, someone else is the local dealer for Stromer in Austin. After doing a futile search on Stromer's site to confirm the seatpost diameter, then all @Kieren needs to do to resolve this question is look along the seatpost that came with the bike for a small set of stamped numbers. The one with a small circle with a vertical slash through it is your seatpost diameter. Given that most seatposts are scratched at the very least or somewhat greasy, check that number again after cleaning the post or use a set of calipers to measure the diameter.
Thudbuster / Body Float
- Thread starter Bobstoltz
- Start date
The Front Ranger
Member
Seatpost ODs can very wildly. I've seen my share of 'posts that would measure differently depending on where you took the measurement.
The three most common seatpost sizes (diameters) for modern bikes are 27.2, 30.9, and 31.6 mm. Where it gets confusing is when you factor in the frame's seat tube OD and seatpost clamp's ID. For example, my Jeff Jones frame has a 28.6 mm seat tube, 31.8 mm seatpost clamp, and 27.2 mm seatpost.
The three most common seatpost sizes (diameters) for modern bikes are 27.2, 30.9, and 31.6 mm. Where it gets confusing is when you factor in the frame's seat tube OD and seatpost clamp's ID. For example, my Jeff Jones frame has a 28.6 mm seat tube, 31.8 mm seatpost clamp, and 27.2 mm seatpost.
The Front Ranger
Member
What size do you need? I have a used one that I'd consider selling.
The Front Ranger
Member
I was referring to the seatpost diameter/size. The post I have is 27.2 mm.
mrgold35
Well-Known Member
I also have a Radrover and went with the Suntour NCX SP12 27.2 X 400mm seatpost ($90, ebay) with a Sunlite cloud-9 12.5" X 11.5" saddle ($30, Amazon). A very comfortable combo for 18-22 mph commuting, long distance PAS 2-3 riding of +35 miles, and trail riding with the Radrover. I'm 6'3" and 265lbs+ 20-25lbs of riding gear and a full backpack (work cloths, lunch, extra riding gear, etc...) for my work commutes. When I got my Radrovers in Sept/16, I was around 280lbs. The Suntour hasn't let me down and it handled the extra weight with zero problems.
You can adjust the Suntour with an Allen wrench to fine tune the amount of support. I ordered two Suntours and one didn't come with a cover. I ordered the Cane Creek Thudbuster cover from Amazon and it fits perfectly over the Suntour.
Suntour with Cane Creek cover and Cloud-9 "Big Butt" seat:
(Link Removed - No Longer Exists)
I scored a BF at a garage sale today on the cheap. Works perfect, Got lucky with the springs and diameter. Makes a huge difference. I learned that thudbusters take shock loads but the BF when adjusted correctly keeps your seat "floating" with the spring tension. Hence the name Body Float.
The tires are wonderful. I've even stripped off the battery on occasion, inflated the tires to 80lbs and ridden the st1 as a regular bike. This morning in michigan and its snowing...Bike time !!!! Deflated the tires down to 40 lbs and had a blast with a headlight.
I was definitely sight riding to the local diner for breakfast
The body float is a great add on to the bike . Bought the body float from CL and a cloud 9 off amazon...Game changer
George Jetson
Member
Ordered a Body Float today at a great price.
mrgold35
Well-Known Member
I just switched from the Suntour to the BodyFloat 2.0 on my Radrover (27.2, 350mm, orange springs) on my Radrover.
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) of the 380mm carbon fiber BodyFloat if I had a thinner seat at my height and 34 inseam.
The BodyFloat and Suntour are about even on smooth paved roads/bike paths (as you would expect). I get a little more bounce/dips/float on the BodyFloat on larger bumps or undulating trails compared to the Suntour. That could just require me to do more fine tuning on the BodyFloat to reduce the bounce/float (currently have it set around 2-3 on the 1-7 firmness scale). The BodyFloat is far superior with much smaller bumps, ripples, 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 the vibrations. I can see the BodyFloat being the better choice if you find yourself riding on broken pavement, uneven sidewalk/paved road cracks, pockmarked/washboard/bumpy trails, and brick/cobblestone roadways compared to the Suntour.
The Suntour for my bike set-up and the way I ride is the 80%-85% solution. 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.
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) of the 380mm carbon fiber BodyFloat if I had a thinner seat at my height and 34 inseam.
The BodyFloat and Suntour are about even on smooth paved roads/bike paths (as you would expect). I get a little more bounce/dips/float on the BodyFloat on larger bumps or undulating trails compared to the Suntour. That could just require me to do more fine tuning on the BodyFloat to reduce the bounce/float (currently have it set around 2-3 on the 1-7 firmness scale). The BodyFloat is far superior with much smaller bumps, ripples, 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 the vibrations. I can see the BodyFloat being the better choice if you find yourself riding on broken pavement, uneven sidewalk/paved road cracks, pockmarked/washboard/bumpy trails, and brick/cobblestone roadways compared to the Suntour.
The Suntour for my bike set-up and the way I ride is the 80%-85% solution. 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.
chgofirefighter
Active Member
Bodyfloat IMO, but I don't know much about the thud buster... That's what I have on my ST2 and it works great!
Installed Thudbuster (non long travel) over the winter. Today is my second ride on it. Initially I thought my seat was loose. It moves easily when you get on it. Realized it was the seat taking up the initial slack on sitting. Its a non issue, just an anecdote, and going forward I wont even notice it (and didnt the 3rd and 4th times I mounted the bike) I have the firm elastomer installed and am 250lbs. The seat will give a bit when I bounce on it, but it's not cushy. So there is travel to be had, but it will likely just be enough to remove shock from a sharp bump, but doesn't make it cushier to ride. I'd have to try the bodyfloat to form an opinion which is better. For many riders, I think the seat not jouncing constantly is a plus, as it doesn't affect efficiency while pedaling. I was expecting a cushier ride similar to one of the cheap $20 style suspension posts mounted on a different bike I tested. I'm not disappointed, as it will serve a function, esp. for potholes. Just my comments in case others think its going to make the seat feel like it has 6" of foam, which was my original rational for trying it. Hopes this helps other with decision points.
Update - Few more rides, and have had some events where I felt the seat give nicely due to dips and bumps in the road. The road surface seemed flat, yet there are imperfections I didnt notice until the post did its job, and it works with a very smooth action. Really liking it.
Update - did about 1km of offroad today, firm clay with a ton of smooth rocks - nearly cobblestone rd only rougher. sharp ups and downs. Some steep hills. Seat could likely go to the next elastomer down, even though I have the recommended one for my weight. It did give on the worst, but not by much. It's probably doing more than I give it credit for, and I had to be off the seat a fair bit anyway for the hills.
At this point I think this ST version is great for pavement, but the LT would be better offroad.
Update - couple more weeks of riding - have gotten used to the elastomer sized for my weight (firm). Meant to do a softer one as a trial, but with more miles on this one, I've gotten used to the feel. Have noticed on several occasions that the seat post is indeed working just fine, without being too plush. Nice controlled cushioning on bumps. Last 2 weeks have all been on pavement. Quite pleased with the Thudbuster, now I put the time in on it. First impressions were I wanted something softer, but as of now this is working out perfect.
Update - Few more rides, and have had some events where I felt the seat give nicely due to dips and bumps in the road. The road surface seemed flat, yet there are imperfections I didnt notice until the post did its job, and it works with a very smooth action. Really liking it.
Update - did about 1km of offroad today, firm clay with a ton of smooth rocks - nearly cobblestone rd only rougher. sharp ups and downs. Some steep hills. Seat could likely go to the next elastomer down, even though I have the recommended one for my weight. It did give on the worst, but not by much. It's probably doing more than I give it credit for, and I had to be off the seat a fair bit anyway for the hills.
At this point I think this ST version is great for pavement, but the LT would be better offroad.
Update - couple more weeks of riding - have gotten used to the elastomer sized for my weight (firm). Meant to do a softer one as a trial, but with more miles on this one, I've gotten used to the feel. Have noticed on several occasions that the seat post is indeed working just fine, without being too plush. Nice controlled cushioning on bumps. Last 2 weeks have all been on pavement. Quite pleased with the Thudbuster, now I put the time in on it. First impressions were I wanted something softer, but as of now this is working out perfect.
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For anyone on the fence about what one to buy... My problem, was I ordered the Rad Mini step thru. RAD states that the max rider height is 5'10", I'm a around 5'11" so, I'm kinda worried I won't have the full extended leg length, my inseam is like 31" that is the max also listed on the site... I also weigh 230 lbs.
Anyway, no problem, I'll just find a longer seatpost, better yet! I'll get one even longer... Suntour only offers 350~400 MM lengths. But is the cheapest out there for about 110 bucks. But... You'll have to upgrade the spring to a RED one (that is currently out of stock) for another 15 bucks if you are a heavy rider... (at the time of this writing)
Next is the ThudBuster. I was having a heck of a time trying to find the seatpost length, so I emailed them and this is the reply I got...
Hi Eric, we have an XL version of the Thud LT which is 450mm long. It will work fine with the saddle you linked. Part# for the 27.2mm version is ST3272KXL. The standard Thud LT is 400mm length, and the ST is 350mm.
Cheers
Drew
So... that cost around 180 bucks for the XL version. And, also, note, that I am outside of the weight limit on the rubber things they put in the seat, and according to the manual, I'd need to buy extra ones to accommodate 230 lbs. So... that would put into the bodyfloat price of shy of 50 bucks.
Next!!!
Bodyfloat... A dream come true? 420 MM seatpost! Yes, that's the ticket, I only need an inch or two more height. Much better than a 450 MM post (for my needs). Plus, it's setup for my weight 200~250 lbs. No trying to figure out buying extra parts that may or may not be in stock. Perfect for my needs...and yes, 250 bucks maybe a lot of $ and it kinda is... But I think in the long run, it will be worth it.
So, after all the confusion and time researching to figure out how to get an XL seat for my rad mini... I bit the bullet and got one that ticked off all the boxes to fit my needs perfectly. I should also note, I also bought the comfort seat could 9... So my butt riding will be floating over bumps, in a could of gel comfort. LOL
https://www.amazon.com/Cirrus-Cycle...es+KINEKT+2.1&qid=1558378606&s=gateway&sr=8-3
Conclusion: If thudbuster or suntour made a post that was 420 MM (I suppose you could cut it to fit if one got a 450 MM)... and came with all the rubber things or springs to support my weight, I would have probably cheaped out and gone with them to save a 100 bucks. But, after looking at the springs on the suntour, and the rubber garments on the thudbuster, you can see that that the bodyfloat is going to probably be the winner of them all for superior comfort and longevity. Might as well pony up the money now than later.
I'll follow up on how it all worked out when I get it.
Anyway, no problem, I'll just find a longer seatpost, better yet! I'll get one even longer... Suntour only offers 350~400 MM lengths. But is the cheapest out there for about 110 bucks. But... You'll have to upgrade the spring to a RED one (that is currently out of stock) for another 15 bucks if you are a heavy rider... (at the time of this writing)
Next is the ThudBuster. I was having a heck of a time trying to find the seatpost length, so I emailed them and this is the reply I got...
Hi Eric, we have an XL version of the Thud LT which is 450mm long. It will work fine with the saddle you linked. Part# for the 27.2mm version is ST3272KXL. The standard Thud LT is 400mm length, and the ST is 350mm.
Cheers
Drew
So... that cost around 180 bucks for the XL version. And, also, note, that I am outside of the weight limit on the rubber things they put in the seat, and according to the manual, I'd need to buy extra ones to accommodate 230 lbs. So... that would put into the bodyfloat price of shy of 50 bucks.
Next!!!
Bodyfloat... A dream come true? 420 MM seatpost! Yes, that's the ticket, I only need an inch or two more height. Much better than a 450 MM post (for my needs). Plus, it's setup for my weight 200~250 lbs. No trying to figure out buying extra parts that may or may not be in stock. Perfect for my needs...and yes, 250 bucks maybe a lot of $ and it kinda is... But I think in the long run, it will be worth it.
So, after all the confusion and time researching to figure out how to get an XL seat for my rad mini... I bit the bullet and got one that ticked off all the boxes to fit my needs perfectly. I should also note, I also bought the comfort seat could 9... So my butt riding will be floating over bumps, in a could of gel comfort. LOL
https://www.amazon.com/Cirrus-Cycle...es+KINEKT+2.1&qid=1558378606&s=gateway&sr=8-3
Conclusion: If thudbuster or suntour made a post that was 420 MM (I suppose you could cut it to fit if one got a 450 MM)... and came with all the rubber things or springs to support my weight, I would have probably cheaped out and gone with them to save a 100 bucks. But, after looking at the springs on the suntour, and the rubber garments on the thudbuster, you can see that that the bodyfloat is going to probably be the winner of them all for superior comfort and longevity. Might as well pony up the money now than later.
I'll follow up on how it all worked out when I get it.
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