Broken Miyatas

A few weeks ago, I had a puncture in my saddle of my MUni. What had happened was that the metal inside of the seat had snapped. Thus making a hole in the pillow and popping my inner tube. I replaced that base with a CF one.

Just this weekend, I noticed that my trials saddle seemed to be REALLY flexi. Also, the air inside the saddle seemed a bit low. I pumped it up, but within a matter minutes I was empty, and I hadn’t even sat on it! The same thing had happened. The metal plate inside snapped, and made a hole in the inner tube. You can see on the plastic base, were it had been flexing.


I am getting a CF base on Thursday, so that is ok…
Has anyone else broken many of them, and how long did it take you?
I have had them both for about a year.


My Miyata saddle snapped after 2 years of use, though the first year I wasn’t doing very extreme stuff. I didn’t have any problems with my air pillow though because I had it in a Roach cover simply fitted over the stock Miyata foam cushion and vinyl cover. I took the cheaper route and purchased another plastic base and a GB4 stiffener plate (which seems like more than enough for me.)

BTW, George Barnes, if you read this, are there any plans for a similar KH stiffener plate? Several people (including John Glazer of the HoW gang) have busted their seat post bolts through the plastic base of their KH seat. I thought this was maybe just a problem with the older KH seats that lacked a metal plate, but it looks like John’s has a thin metal plate in it.

I snapped the seatpost on my old miyata. That was a couple of years old. You can’t buy Miyata seatposts in the UK any more, so my miyata seat is currently dead.

I’d recommend drilling your carbon fiber base out for a standard bolt pattern so you can buy a spare post when you break the current one.


I have broken many Miyata seats and posts over the years. It’s amazing, though, how many design changes they’ve made since I first saw the plastic seats in 1980. They make constant improvements, but the seats just aren’t intended for the rigors of Trials and adults constantly pulling up and pushing down on them.

If we didn’t put so much force into the seat handles, the seats would hold up forever. I expect future unicycle designs to include handle systems that are not part of the seat but instead come out of the seatpost or frame.

Until then, Miyata and Velo (Kris Holm) saddles are still the best you can get without customizing.

My miyata seat is staring to get really flexy. I was thinking about getting the GB4 Stiffener plate for it. If my seat is already breaking, is it too late for the plate?


Broken stiffener plates in the Miyata seats is very common if you use the seat for muni, trials, or advanced freestyle. The stiffener plate is thin stamped metal. It’s not designed for aggressive use.

Constant pulling up and pushing down on the seat handle like you do on muni rides will cause the stiffener plate to break like that. Landing drops will break the seat if you end up sitting on the nose of the saddle. Freestyle skills like hopping on the wheel and side ride will also break a standard Miyata seat.

I used Miyata seats on my Pashley muni. I wasn’t riding too aggressively at the time (it was only a Pashley with a skinny XC tire) but it got to the point that the life expectancy for a Miyata seat was less than a month before the stiffener would break and the nose of the seat would collapse. I tried various ways to reinforce the seat but without having access to a machine shop where I could make a custom stiffener plate I was out of luck. I switched to a carbon fiber base at that point. The good thing is that since I broke so many Miyata seats I had plenty of spare Miyata parts for my carbon fiber seat upgrades.

Now we have the GB4 Stiffener Plate. I could have used that back when I had the Pashley and the standard Miyata seats.

I just saw this thread, sorry for the late reply.

daino - If you haven’t broken it yet, I don’t see why you couldn’t add the stiffener and use your existing base.

hell-on-wheel - The next time I speak with I will bounce the idea of them and go from there. I think most of us have seen the one proposed solution to stiffen up the KH. I don’t know why I couldn’t get a fixture made and produce something similar pretty economically.

I couldn’t find the picture I referred to right now, but surely someone can repost it. The one thing I did not like about that solution was that it required a special seatpost.

Given the breakage stories and the fact that my own Velo is getting flexy I’ll give this a little more thought.