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-   -   Adjustable steerer adapater (Speedlifter, Octagon etc) - how safe is it? (https://www.bikeforums.net/showthread.php?t=1172792)

Morimorimori 05-12-19 05:17 AM

Adjustable steerer adapater (Speedlifter, Octagon etc) - how safe is it?
 
Hi, everyone.

I've been thinking of installing that device on my bike, to be able adjust my sitting posture during the ride, depending on my mood and other circumstances. The one I decided to try is shulz's Speedlifter Pro (as it gives the longest adjustable range, up to 14 cm):
http://uk.byschulz.com/wp-content/up...ter_manual.pdf

I wonder, though - how safe is it for everyday riding? I'm not doing any extreme stuff, just a regular urban commuting and roaming the streets and countryside. But I still have to do a very basic "bike acrobatics" on regular basis, like a bunny-hop - as our urban area isn't well-suited for bikes (you basically run along the regular pedestrian passways all the time, full of obstacles which are not an issue for a walking human, but are for a cyclist). So I'm worrying how tight it all is sticking together.

After reading the installation manual, I see that this system doesn't make use of the star nut. That's the part that worries me most.

Any thoughts?

aggiegrads 05-12-19 06:12 AM

I would rather use the Grant Peterson method of installing drop bars very high. You can ride in drops when you are feeling good and use the hoods or tops when you want to sit up.

If you can add some spacers and put on an “up-jutter” stem, you will have saved considerable weight, complexity, and “reversibility”. The installation on the speedlifter looks permanent, and as you already observed, does not appear to give the user a good way to adjust the headset.

This is also a good case for a long quill stem. Only one bolt needs to be loosened to raise the bars, and can give considerable adjustability. You would have to replace the fork and headset, but this should not be a problem with a normal head tube. If you have tapered or oversized head tube, then you are out of luck.

andrewclaus 05-12-19 06:48 AM

It looks dependable. Is it made in Germany? I'd trust German engineering.

The star nut doesn't provide any strength, just easy adjustment. I used an old Aheadset from 1996 that did not use a star nut, and I still see them at the shop once in a while. Adjustment was by a split cone arrangement.

If you install it, which looks fairly complicated and permanent, be sure you lengthen the brake and shifter cables too.

HillRider 05-12-19 07:09 AM

There does seem to be a method for adjusting headset preload with this thing despite not having a starnut. The Speedlifter clamp has a 36 mm hex nut on the bottom and you use a headset wrench to make the adjustment after the clamp is tightened in place. Look at 1:20 to 1:26 of the video.

That said, this thing is completely unsuited to a carbon steerer and I'd highly recommend against adjusting it while actually riding.

leob1 05-12-19 10:50 AM

The star nut just preloads the headset bearings, it doesn't hold the fork on the bike, the stem does that. This looks like is solves the issue of not having one.
Other than that, it looks like a solution looking for a problem.

fietsbob 05-12-19 11:40 AM

I've seen them on single size Cargo bikes such as https://www.larryvsharry.com/..

no curb hopping in those .. the bike then may be shared by multiple riders ..
then the height adjustability is practical .. messenger fleets..


But I still have to do a very basic "bike acrobatics" on regular basis, like a bunny-hop - as our urban area isn't well-suited for bike
then why go there? find another route ..
got a long steel steerer threadless fork * ? add more spacers..

* it shows you need that to install it..





...

Morimorimori 05-12-19 12:22 PM


Originally Posted by aggiegrads (Post 20925642)
I would rather use the Grant Peterson method of installing drop bars very high. You can ride in drops when you are feeling good and use the hoods or tops when you want to sit up.

I'm not that sure about the drop bars, tbh. They all feel too narrow for my taste. I prefer the idea of city/beach bike, where you run while sitting straight, or leaning forward a bit, and have a wide, comfortable handle bar, with more precise control when you turn.


Originally Posted by aggiegrads (Post 20925642)
If you can add some spacers and put on an “up-jutter” stem, you will have saved considerable weight, complexity, and “reversibility”. The installation on the speedlifter looks permanent, and as you already observed, does not appear to give the user a good way to adjust the headset.

Yes, it's kind of permanent. I still would like to give it a try and call it an experiment. Then if it won't work that well, I can resort to something else. The only thing that worries me is whether it's safe enough.

Morimorimori 05-12-19 12:27 PM


Originally Posted by andrewclaus (Post 20925672)
It looks dependable. Is it made in Germany? I'd trust German engineering.

It's designed by german engineer(s), but where it's made is a big question :) You can't tell this really well these days :)


Originally Posted by andrewclaus (Post 20925672)
The star nut doesn't provide any strength, just easy adjustment. I used an old Aheadset from 1996 that did not use a star nut, and I still see them at the shop once in a while. Adjustment was by a split cone arrangement.

I always thought the star nut is what fastens fork in the head tube, isn't it?


Originally Posted by andrewclaus (Post 20925672)
If you install it, which looks fairly complicated and permanent, be sure you lengthen the brake and shifter cables too.

Yea, that's a good point, thanks. Shouldn't be a problem though.

Morimorimori 05-12-19 12:39 PM


Originally Posted by fietsbob (Post 20926134)
then why go there? find another route ..

Well.. It's not like we have a lot of options here. You, of course, can move only along a couple long enough bike lanes or along a very few streets city's officials deliberately decided to make suitable for bikes - if you are lucky and your destination is somewhere near one of those. Or you can spend a lot of time finding another routes which is more or less passable without need to jump off your bike and carry it over something, or bunny-hopping. Or you could just learn a few tricks and ride whenever you want, without boring route planning phase (that's what I prefer :) ).

The approach you mentioned is more or less suitable for commuting, but not that much for for-fun riding which I also do quite often. Sort of urban free-ride thingy, when I just run my bike in random direction, for site-seeing and a bit of fresh experience. You don't really want to plan route while at something like this :) It sort of steals the feel of freedom which gives bike riding so much joy. For me, it was just better to learn the bunny-hop, and it's enough to traverse 90% of obstacles on my way (usually it's high curbs, 10-20 cms).


Originally Posted by fietsbob (Post 20926134)
got a long steel steerer threadless fork * ? add more spacers..

* it shows you need that to install it..

Yup, I have exactly that kind of new fork. Had to buy it anyway as my current one doesn't have mounts for disk brake calipers, so I deliberately searched the steel threadless one.




...

Ironfish653 05-12-19 01:01 PM


Originally Posted by Morimorimori (Post 20926180)
I always thought the star nut is what fastens fork in the head tube, isn't it?

You use the star nut to set the preload, but the stem clamp around the steerer is what keeps it all together.



It looks pretty well thought out, and the swivel is nice if you're tight for storage space. Someone mentioned cargo bikes, I think there are some folding bikes that use a similar setup.

Personally, I just don't see the need for an on-the-fly bar height adjustment. Other than fleet/rental bikes and folders.

If you feel like you need a little bit of height adjustment, an adjustable-angle stem might be a less-involved way to get it.
Either way, I would go easy on the curb-hopping and practice learning how to land 'light' on the front.

https://shop.fullspeedahead.com/medi...st-os-150a.png

fietsbob 05-12-19 02:29 PM

Probably make the front of the bike heavier, and then your bunny hop becomes a face plant
when you fail to get the front wheel up & slam instead, into the curb.

roll the dice ... :D

Morimorimori 05-12-19 03:39 PM

@Ironfish653, I see, thanks for the info.

@fietsbob, should be just fine: I have IGH in the rear, it's heavy enough to balance it out :D

fietsbob 05-13-19 07:44 AM

I fitted a BBB BHP 21, an internal quill based stem raiser , removed the star nut to do so..

their clever design featured a unique bolt , both hex broached and threaded.. ..







...

Morimorimori 05-13-19 06:06 PM

@fietsbob, thank you, it's an interesting option. May be I'll try it, if this one won't work for me. What is your riding stile? Have you put it to a test on some rough rides, by any chance?


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