Anyone else have this problem? Two broken seatposts in a month with KH muni handle

I have had two of my nimbus seatposts break in the last month! A quick search of the forum didn’t bring up anything recent about this.

I believe this is from the KH muni handle and how I ride with it. I hold and pull the handle both when hopping and on steep climbs. The added length from the handle adds leverage to the force I am pulling up with and this is transmitted directly to the seat post joint. Repeat a thousand times and voila!- I am hiking it back to the car.

Attached are pictures of the two broken posts and of my intact setup prior to the breaks. Should I not be holding the muni handle when hopping? Anyone else have this happen? Advice?

Thanks,
Paul

intact.jpg

I’ve ALWAYS been worried about a problem like that with the KH T-Bars, you’ve just confirmed by fears! Though two breaks in however many thousands of people have one isn’t much of a confirmation, the fear is renewed :frowning:

That’s a total bummer, have you considered using a cheaper steel ‘club’ seat post instead? Steel is a lot better at dealing with the repeated flexing than aluminum, it just seams a little funky to put a “cheap” post on such nice uni’s. There’s also the option of the KH forged seat post with adjustable head, the head is cnc’d and seams to be nicer made overall. I’ve never had this problem because I’ve been using the newer pivotal seatpost and zero saddle w/muni handle and it just flexes like crazy instead of breaking.

try a stronger seat post. with the kh seat post for the zero saddle (pivot saddle post, in ever had this problem again). I really love the zero saddle. otherwise find a reinforced seat post.

I had the same problem. As a previous poster mentioned, you should buy the next-generation seat-post, the one with the two hex adjustment screws for angling the seat forward and backward. That is what I have on my 26" mUni, and, knock-on-wood, it’s still working fine.

You might search through some old threads comparing the KH T-Bar with the Nimbus Shadow Handle. The Shadow is a much more rigid, strong setup, AFAIK. I have it on my 29" XC/mUni and have grown increasingly fond of it. However, there’s a weight penalty with the Shadow. The T-bar, by contrast, feels a little bit squishy, but I suppose it would break off if it were too rigid.

Kris seems to be responsive to the issues with current-generation gear, and he comes up with solutions in the next generation.

I am definitely going to move to the pivot seat post- although another unicyclist commented on my Strava feed when I posted pictures that he had broken the bolt connecting the zero saddle to the seat post.

Probably not going to go with the Nimbus Shadow handle since I had one break after hitting the pavement too many times last summer (yeah I know people will think I am abusing these things and the problem isn’t the equipment… :roll_eyes: )

In thinking about this some more, for muni at least, where the touring handle is not that long, would it make more sense for it to slide into a mount that is fitted on the seatpost tube rather than on the seat? Or would it be too prone to getting knocked off-center?

I think you should ask UDC to refund you the cost of both seatposts.

I break a seatpost about every 18 months on average. Probably broke at least 4 now. They started breaking after I began doing more rolling hops on my Muni. I don’t feel I’m putting a lot of force on the handle, but I have a carbon fiber base and a reeder handle (steel), so there’s zero flex to absorb the repeated pulling of the handle.

My 20" used to have the Nimbus alloy seatpost shown at the start of this thread. It broke at exactly the same spot, but I don’t even have a muni handle, I just do a lot of stair hopping.

When I replaced that alloy seatpost with a Nimbus CrMO seatpost, I started a thread comparing them. A guy named Brian O confirmed that the CrMO seatpost is indeed much stronger, and he has posted videos of some crazy jumps, trials and muni riding, all on a 36-inch wheel, so if anyone would know which seatposts are strong, it would be him! In any case, my replacement seatpost has not broken.

My seatposts were probably that old at least. Were those that you have broken all Nimbus alloy posts?

I like my touring handle attached to my seatpost. There are a couple of ways to do it. I use a Coker Pi Bar, but there are solutions that allow use of the Nimbus/KH t-handles as well. search the forums and you’ll find many options.

As far as the concerns about it turning…
It only needs to be tight enough not to move when you are using it. If it is allowed to move in a crash it lessens the chance of braking something (stem, handle, seatpost…). So, I’m of the mind that it is better to have parts that can move if they need to. This goes for brake levers too.

No, I’ve broken GB4 universal seat posts and Miyata posts. The Miyata is kind of cheap steel; the GB4 is built way better.

It’s not uncommon to break seat posts, see these threads:

http://www.unicyclist.com/forums/showthread.php?threadid=24034

Hi,

as mentioned above. Go for a steel Seatpost, or a reinforced Aluminium Seatpost:

Rgds
Thomas

Thanks- good to know I’m not the only one. However I saw those threads but they are both 12+ years old- thought maybe better equipment had solved this issue.