At least it was advice. I missed the part where you were being helpful.
From Brock:
Oh ye spoilt newcomers. Your unicycles break so rarely ye don’t even understand the whys…
It’s called metal fatigue. You don’t have to do anything once real hard, you just have to do it lightly, thousands of times. I have killed probably a dozen seat posts like that over the years, of various brands. The problem today is that the seats are so much stronger (and stiffer), it puts more of the force into the post.
That’s why several of my newer unicycles have gussets on the post, to shore them up in this area. Basically, where we are now, we’ve fixed most of the problems with unicycle seats. The seats don’t break, but the stresses are still there.
It’s the same story with axles. Giving a unicycle a rating for how high you can drop isn’t really an accurate way to gauge its strength. Because if you hop up and down curbs or stairs all day, for a week, it’ll probably kill any square-taper axle, regardless of brand. Metal fatigue.
you seem to miss the point of forums, Obie. they’re to talk to people, and discuss things. I know that whenever I break part of my unicycle, I like to log on to unicyclist.com and brag about it, regardless if there’s been posts about OTHER unicycles that have been broken already.
Brock, tell Ryan, Jess, Zack, me, and many more that you won’t break anything seat out. I broke two KH saddles seat out, Ryan’s broken cf bases seat out, as has Zack. If you are riding an old school 1st or 2nd gen KH saddle Brock, i would bet you’ve already broken the reinforcement plate. I did that part in 3 days.
John Foss explained pretty well what happens to the posts, but to go a bit more into depth:
Aluminum is a crappy material for flexing. That’s why you never see springs made of aluminum. It will crack and break if flexed repeatedly. Steel on the other hand, flexes fine. Yes, it’s better not to flex it, but with the right alloying and temper of steel, you can repeatedly flex it and it won’t break. That is a small reason why you shouldn’t make aluminum seatposts such as found on the KH trials.
I honestly don’t believe there is a good design for unicycle seats. Trials puts severe forces on opposite ends of the sadldle, so there’s no simple solution by clamping just below the handle or rear bumper. To clamp to both would get very heavy and impede riding, along with making the seat dangerous for falls. There are some times when you want the seat to break, and a seatpost supporting the front and back of the seat won’t allow breakage, setting you up to get hurt.
Please let me/us know how these breaks happened.
Recently, I have had a lot of luck not breaking things by keeping my uni on trails (rather than urban) and by doing seat-out as much as possible.
Well, Zack broke his on a 5’-ish drop. You can hear it break on the video, but he salvaged some of the cf to use as a reinforcement plate. I think he’s broken two of them now, but i’m not sure. I don’t know how Ryan broke his, but I have seen pics of it and it was definitely broken due to seat out. I broke mine just doing lots of seat out and seat in rolling hops and sidehops and steep hills.
If the CF seat base broke on a seat out jump or drop then I’d bet that the seat was already cracked from previous abuse. The crack could have started after a big seat-in move and it was just the seat-out move that finally did it in, but the damage had already been done.
