Thanks to soem really good siggestions from some people, I’ve made a few alterations to my frame design. It’s still the same shape and everything but:
Instead of 20mm x 35mm ovalised tubing, I’m using 15mm x 30mm
15mm side clearance to 8mm
30mm top clearance to 25mm
10mm thick foot rest to 5mm
About a 29 - 30mm diameter seatpost post section of frame.
Would it be better to make my own seat post? This way I could have the nice Miyata saddle with a thick seat post instead of a 22.2mm one. Is it very easy to make a seat post and the bit that attaches to the seat?
Andrew, with a 29mm seat tube on your unicycle you could probably use a bicycle seatpost. You may or may not need a shim depending on what sort of seatpost you’re getting. Advantage of this is that you could then adjust the angle of your seat. However, that would mean getting a wilder bracket to attach to your saddle:wilder bracket
Either that or you could probably try making your own rail-adapter. But hey, if you’re prepared to make a seatpost anyway you might as well try making an adapter instead.
Or modifying a bicycle seatpost to bolt directly onto the seat. I’m not sure if this has been tried, but I have been considering it for a while. It would save a lot of weight and allow the seat angle to be changed.
I made a railed seat bracket with a brake mount ,I used the old miyata post
and some fresh cold roll.
I think 27.2mm perfect for a seat tube on a MUni and works good ,and you
can use a Q release ,and a susp post now also.It’s easy if you got a shop.
My Muni is bomber now.I had a great time beefing it up.I only wished we had
a tig welder,
we used a mig ,you still can’t tell but a tig would be the best for looks.
“andrew_carter” <email@example.com> wrote in
> Thanks to soem really good siggestions from some people, I’ve made a few
> alterations to my frame design. It’s still the same shape and
> everything but:
> - Instead of 20mm x 35mm ovalised tubing, I’m using 15mm x 30mm
> - 15mm side clearance to 8mm
> - 30mm top clearance to 25mm
> - 10mm thick foot rest to 5mm
> - About a 29 - 30mm diameter seatpost post section of frame.
> Would it be better to make my own seat post? This way I could have the
> nice Miyata saddle with a thick seat post instead of a 22.2mm one. Is
> it very easy to make a seat post and the bit that attaches to the
> | Attachment filename: frame.jpg |
> |Download attachment: http://www.unicyclist.com/attachment/87759 |
> andrew_carter - I’m getting a custom mountain uni!
> Thanks everyone for all the help and advice you’ve given me over the
> past few weeks. This is the custom unicycle I’ve decided on:
> - Profile hub and cranks, Alex DX-32 24" rim, Miyata saddle, Some good
> spokes and pedals, 24 x 3" tyre (probably Gazz), Custom-made frame
> painted a nice orange (like on the KH24) or green.
> andrew_carter’s Profile: http://www.unicyclist.com/profile/1052
> View this thread: http://www.unicyclist.com/thread/21540
Thanks everyone. I think for the seat post I might try what James has done. That would mean the I could choose any seat post size I wanted. Would this be very hard to do? And also, is there any problem with drilling screws into a Miyata seat?
The wilder bracket does seem like a really good idea. Maybe I can get it later if I need to. Those holes at the top of it where the screws go through, would they be in the right position for most unicycle seats (particularly the Miyata)?
The holes for the Wilder bracket fit the Miyata seat.
You can make a rail adapter for a unicycle seat. The person making your frame could also make you a rail adapter. They’re not complicated. It would certainly be cheaper to make one than to ship a wilder bracket to AU.
Using a bicycle seatpost is so much better than a unicycle seatpost. With a bike post you can adjust the angle to your liking. And even the cheap bicycle seatposts are better than the best unicycle seatpost. I’d go for a frame that fits a 25.4mm or 27.2mm bicycle seatpost because those sizes are common.
I think the best option is to be able to use a bikie seat post. Then I can also use a quick release mechanism from a bike as well and it’ll be the right size. There is one thing I’m not sure about though. Those rails look like they stick out a long way from the bottom of the seat. I don’t particularly like the look of this. Would there be any room to make the rails closer in to the seat? Also, does anyone have any photos of other unicycles with rail adapters attached to them?
Are there any problems or improvements to be made on the frame design?
It must have sounded strange when I said, “And also, is there any problem with drilling screws into a Miyata seat?” I didn’t realise then that the screws actually come out from the seat and don’t go into it.
You could make the rails closer to the bottom of the seat, but there needs to be enough space so that the seatpost guts (the parts that clamp on the rails) can fit in there. You can’t reduce much space before it becomes very difficult or impossible to fit the seatpost guts in there.
It’s already difficult to angle the seatpost guts in the Wilder bracket without removing the bracket from the seat base. Making the space smaller would mean that you would have to remove the bracket from the bottom of the seat to install a new seatpost.
The idea I mentioned before might solve your problem- I have yet to fiddle around with it but basically quite a few bike seatposts like theThompson seatpost have a flat top plate. You could probably make a new top plate which is bigger, wider, curved, and drilled to fit the miyata seat. That would allow seat angle adjustment. It won’t allow you back and forths adjustment but I don’t think that makes a difference on a Uni.
John is right on as usual - I’ve tried to keep the rails tucked up as close to the seat as possible on the adapters I’ve made. A unicycle seat is so narrow in the middle that the rails must extend below somewhat though.
Joe Rowing wrote:
This would be the next step in the evolution of the unicycle saddle. I’m a big fan of using bicycle seat posts on a unicycle. A bike post is lighter, cheaper, stronger and allows saddle tilt adjustment. You can buy a GREAT bike seat post, like I did, for $6.95 or spent as much as $150.00 for a carbon fiber/titanium feather light thing. A unicycle saddle with integral seat rails would be great!
I’ve been working on this for a while and there’ll be some photos eventually - when I’m happy with it.
It’ll be a carbon seat with integral rails and an integral handle. however all of the loads go through the rails and seat so you won’t have the myata style problems
well, other than what I’ve told you there’s not a lot to tell -
I’m painfully aware that if you overstress carbon composites they can shatter - not good in a seat.
that and i think the idea of putting the handle loads through the seat is not a good one.