Need help with seat post size

I’m unicycling again at the age 59 on my Emory 24" unicycle! So far the only downfall is the original hard seat that is making it uncomfortable and awful to ride! After some research, apparently the seat doesn’t have a standard 4 bolt mount (there are 4 bolts, but not standard in size I guess). I want to buy a new post (or whatever I need) that will accept any of the newer saddles like Kris Holm’s. The outside diameter of my seat post measures 2.75 inches around (see photo). This post size seems odd and small in diameter. What size do I really have in mm? If this post is an odd size, can I buy a standard size post, cut it, and use an adapter of some type to bring it down to the correct diameter that I need? All I want is a new saddle to sit on. I contacted Emory in FL, but they couldn’t help. I’m happy with the unicycle for now, although I see a 29" in my future for my 60th! Any ideas would be greatly appreciated! Thanks!


Uni Seat Post.jpg

Welcome to the forum GRZ :slight_smile:
It really would be a shame to cut up your lovely uni :frowning:
I’d suggest that you bring your 60th Birthday forward and treat yourself to that new unicycle now. :smiley:

( You know You Want To :wink: )

Is it really 2.75 inches?

If you remember your algebra, the outer circle measures Pi x Diameter. In your case, 2.75 inches would mean 22.2mm seat post. Which seems incredibly thin.

Though, after checking on UDC, there seem to be such a size:

No one says you need to cut anything…

That would translate to a what? 22.2mm seat post?

But yeah, I might be tempted to put that $20 toward that new uni you mentioned.

2.75" = 11/4" = 22/8".

Pi ~= 22/7.

22/8" divided by 22/7 = 7/8" = 22.2 mm. Same as my Avenir and Sun unis.

(I heart math.)

Or you could get this one, and it’s only $7 on sale. They don’t even charge extra for drilling it out to make it lighter;)

EDIT: I just measured the post on my old Schwinn, and it is 20.6mm. So with a bit of soda can shim it should be workable in a 22.2 seat tube. Also, Wald used to make a shim to go from 13/16" (20.6) to 7/8" (22.2) because these two sizes were common on American cycles for decades leading into the 1980’s. It is very likely that the new Schwinn seatpost is 22.2 since the older 13/16" size hasn’t been common for quite some time now. Contact UDC to be sure, and they will know the size.

Wow, thanks for the warm welcome and advice here everybody! I apologize for my hasty search for conversions. Glad to see there is a 22.2mm seat post. My renewed enthusiasm is already bad enough without everyone suggesting a new uni! :slight_smile: The plan is to get my current 24" up to date and comfortable to ride, and add a 29" next. You see, I’m already planning on a fleet of uni’s! I need more practice on the 24" before moving up though. I really wanted to add a 36"next, but chickened out after a hard UPD from a small pot hole on the 24". A new post and saddle on the 24" is only the beginning!

The 22.2mm seat post is THE MOST common size for inexpensive unicycles. The base of the saddle looks like that of the appropriately named Savage brand saddle. They are notoriously brutal saddles. Buying a four-bolt, 22.2mm seat post AND a more comfortable saddle might be in order. By the time you’ve decided to spend that $40 to $50 you may want to just consider buying a new 24" unicycle.

Nothing wrong with 22.2mm seatposts in the right place. Although they are often used on cheap unis, they are still tough enough for anything that isnt trials or muni.

A heck of a lot of people (myself included) who play uni hockey in the UK use nimbus X frames which take 22mm seat posts. To say that hockey unis get thrown around is an understatement. I havent seen any seatpost failiures so far vs the death of multiple other parts.

If everything on the unicycle still works and stays tight, a new saddle should make the entire uni feel much more comfy.

I hesitate to throw too many variables into the mix, but a new seatpost isn’t your only alternative. There is at least one unicycle saddle that uses a standard bicycle seatpost, this one (shown below). It’s a Qu-ax Air saddle. Not the most popular saddle around, but not a bad one either. I have one, and after some modifications (flattening the base and enlarging the center “tunnel”), I find it comfortable for cruising. It’s available here:

Good luck, and glad to have another rider on the forum!

Quax Air saddle.JPG

Thanks harper and davejh for confirming the 22.2mm post is not that uncommon. I only plan to street ride, so I’m not worried about strength. Lots of great advice and suggestions here, thanks everybody! There’s something about fixing up my old 24" right now and giving it a new feel that’s that’s really appealing. I’m also thinking what could possible go wrong that would cause me to regret investing a little extra money in a cheap uni that I’m already riding? In a lot of ways, I want to see if I continue to ride so I can justify a new bigger one… or two!

Not too many Emory’s around anymore. It’s interesting that the company still exists, yet they can’t help you with the dimensions on their old products. Emory did a full-color, full-page insert ad in one of the early IUF newsletters (1987 or so), but I rarely saw them. I think they are found mostly in the Southeastern US, as they were made in Florida, if I remember correctly. I never owned one.

I will go in with the group recommending a saddle (and post) replacement. A comfortable saddle can make a big difference between enjoying unicycling, and it just being a chore. Though those old rectangular seats could be fairly comfortable, what they never were was durable. Todays seats can take thousands of drops, suffering only scratches in the bumpers.

The $30.00 saddle, or the identical Nimbus $30 saddle are inexpensive seats that will give excellent, 21st century comfort. They’re still unicycle seats, so don’t expect a Tempur-Pedic experience, but they will serve you well, on that unicycle and possibly on future ones as well.

Thanks for your input. The $30. saddle sounds like it would be a big improvement in comfort, and it looks like there’s a 22.2mm seat post available for $10. I don’t mind spending an additional $45. on a Kris Holms Freeride saddle that I could use on future uni’s, if it’s that much better. Is it a huge leap in comfort?

Most (all?) people agree that modern saddles are more comfortable than what you are currently riding. Once you get past that basic point the consensus starts to go awry. Some people find the Fusion Freeride to be the most comfortable, Some prefer the Fusion street for distance riding, some like the older Nimbus HiTop saddle. I think there are even some people who still prefer Miyata saddles, and maybe Air seats.

So, will the FFR be a huge step up… Maybe. I haven’t ridding a QuAx Air, but I understand that it is a bit wide in the middle and some people find that uncomfortable.

I received my new seat post and saddle today only to find out that my seat post is 22mm not 22.2! Doh! I called and they don’t have a 22mm post, or know where one could be found. So after all that, I’m stuck with my old saddle.

I may look at the saddle LanceB so kindly found and suggested that uses a standard bicycle seat post.

If you have a good bike shop that’s been open for a few decades they may have the tool to ream your seat tube to the 22.2 standard size. New shops seem to be somewhat lacking in frame prep tools.

Also, the 13/16", or 20.6 size will fit with a shim. Ask UDC if the Schwinn post they have is 22.2, or 13/16" if it is like mine it will be the smaller size, and should be workable for your uni.

I’m actually going to buy a new post for my Schwinn, and you’re welcome to my old one if you want it. The holes were originally drilled a bit off, so the post sits crooked. I drilled a set of new holes to put it straight. The hole problem won’t make any difference to you. The Schwinn frame design will work with either post size so it’s a non issue for me.

Thanks for the great suggestions and for your kind offer of your old seat post. There is a bike shop that I’m guessing could ream the seat tube, but I think I’m just gonna grin and bear it with the original saddle at this point. It’s in great condition, just hard as a rock. I thought this would be a simple upgrade that would get me ridding again. My original goal was to brush up on my ridding skills with my old 24" so I could justify buying a new 29" or 36", and be able to ride it with confidence. I don’t want a new 24" at this point. I should have stuck to the old saying, “if it an’t broke, don’t fix it”! I’ve already lost money on shipping both ways and I’m still on my old saddle. Thanks to everybody here on the forum though, I did learn a lot about saddles and seat posts!

Upgraded Vintage Seat Post

I upgraded the seat post on my 50+ year old 26" Columbia uni using a section of 1" pipe that clamps on the outside of the frame post. It fits a modern four bolt saddle and should resist twisting/slipping much better then the original.

The 26er should have a new lease on life. It still has cottered cranks and welded on rubber pedals. I never had any problems with the cranks when I rode it long ago but I hear lots of stories of problems with them. After learning to free mount my 36er I need to work on free mounting this squirrely little thing.

Original Saddle and post:

New Seat Post and Modern Seat:

Ready for service:


“Outside diameter” - you mean circumference.

As other people have posted, the maths suggests a diameter of 22.2 mm which is a common size on cheaper unicycles.

However, measuring round it with a tape and dividing by pi introduces a margin for error. Ideally, measure it with a calliper gauge, or find some way of measuring the distance between two parallel items that are touching it on opposite sides.

A seat post is a cheap and easily replaceable item, but it would be frustrating to buy the wrong size.

After reading the thread I think the original poster was looking for a 20.6mm (13/16") seat post so he could put a modern seat on his vintage uni. It seems that no one sells a 20.6mm OD seat post or the 1" (25.4mm) ID clamp that would be needed.

I was in the same boat so I made a special seat post that clamps over the original vintage frame post. My frame post is 1.000" (25.4 mm) OD without the paint. The pipe I used to make the seat post was about 0.098" ID so I had to bore it out just a little (about 0.003") to make it fit over the original frame post. Seems to work fine and should be a lot stronger then the original seat post and smaller seat clamp system.