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Schindelhauer Stem (31.8 bars, 90-120mm length, black and silver): https://www.goldsprintshop.com/Schindelhauer-Ahead-Vorbau-318-mm-silber-90-mm

Yeah, they are a bit, aren't they.

I think the Syncros is the only one where welds are acceptable as they invented this weld "zit" thing in the 90s. Vintage heritage.
Anyway, more important for this collection than welds is that bolts are minimized and/or hidden, so the Syncros is doing quite well with just 3 bolts in total.

This is supposed to be a collection thread, please help gathering ahead stems that resemble the purist elegance of quill stems, i.e. alloy/steel, but with few/hidden/integrated bolts etc. No fancy crabon road stuff.

Basically any nice stem with LESS than 6 Bolts ;-)

I will start with these three:

Velo Orange Tall Track Stem (31.8 bars, 80-110mm length, black and silver): https://velo-orange.com/collections/stems/products/vo-tall-stack-threadless-stem-31-8-rise

Genetic AQ Road Stem (31.8 bars, 70-110mm length, black and silver): (https://www.tritoncycles.co.uk/components-c9/stems-c76/aq-road-stem-p13383

vintage Syncros Cattlehead (25.4 bars, 100-160mm lenght, black/grey/silver, there is also a version with hinge and a 1" ahead version)

Please add more if you have seen any, I would especially be happy to see more stems like that made for 25.4 bars!

If 1" forks were impossible to obtain

Not as easy. The forks shall be disc forks, but disc forks in 1" are actually almost impossible to obtain

I get your point. But:

in a normal cup, that force is dealt with locally by the cup pushing against the inside of the headtube at that point.

Why should the headtube deal with that force to the full extent, it would be more likely that the cup main section which is sticking out of the heattube and has quite thin walls would be stretched, too.

In the end, there is no way getting around trying it I guess ;)
At least nothing can go horribly wrong, i.e. there's no danger involved if the external cups should gradually go loose.
Of course brazing them to the headtube would be better but then I can't take them off anymore if I have another idea and also I would have to make them out of steel instead of aluminium which takes much more time and effort on the lathe, and theres the extra effort of brazing involved.
Just making two cups out of aluminium would be super easy and fast.

bearings exert an outward radial force on the cups

I understand that point and I am still thinking about it. But, if deformation exerted by the bearings on the cups would be a problem, then even with normal cups in a standard 1" setup for example, the bracing support by the headtube would never be sufficient to prevent a gradual deformation of the cup by the bearings over time, because the headtube is sitting quite a few mm below, not in the same "plane" as the cup itself).
But, apparently reality shows that this is not happening?

One more thing to consider: the bearings itself in my concept are IS41 industry bearings, which usually have a closed stainless steel body. Unlike an open BB ring like it is used in 1" headsets, these bearings offer a certain structural integrity in themselves, helping to distribute any forces coming from the steerer much more evenly onto the cup

In the traditional way the headset cup is supported on both sides, internally by the steerer tube and externally by the head tube.

That's not right, in the traditional way the press-fit section of the cup is supported externally by the head tube (yes), but internally the steerer does not support it, it supports (if you can even call it that) only the cup itself which sits further up. With the press-fit section outside, forces are justed turned inside-out but the support is about the same. And the wall thicknesses (see my updated drawing) are higher too when it's external.

Of course it's always ideal if you use a 1" fork in a 1" steerer etc., but I am proposing a solution for a specific case that sometimes comes up here and there and I hope that people can take advantage from that, and the effort needed is actually quite low as it's really only about making the parts on the lathe. I will try the external cup now, thanks anyway for the input.

they'll be a load of lateral force on the fork steerer that might walk the cups off of the head tube

No offense but this is really not going to happen. Remember that there is the whole ahead force clamping it down. If the lateral forces would actually stretch the material of the cups so they get loose then this would happen with every cup in the world. But it doesn't.

The only way I can see it working well is to make the headset cups totally external

That's what I meant with "external cups". So, how about this (see below). Would be easier anyway, as they could be made from (easier to machine) aluminium then. When the paint has been cleaned off at the headtube contact surfaces and the ID of the cups are matching the headtube, the assembly would be a press-fit, like a normal cup, even if the headtube isn't perfectly circular the press-fit would probably work well enough.
Any thoughts?

I am actually considering to simply do external cups, that might make things easier.
Or I stay internal but go down to 0.6 or 0.5mm wall thickness at the internal section

Yes I meant 0.1mm = 2x 0.05mm.
So you mean the steering could seize?

Ok well depends a bit on headtube preparation/reaming and of course I could always lower the cup diameter very slightly on the lathe

Hi,
regarding putting 1 1/8" forks in a 1" headttube, I have a pretty simple and straightforward adaptor idea (to be machined on my lathe), to accommodate a standard IS41 headset (for example this one) in an old 1" headtube.

This is so simple I am really wondering why no one has done it yet/why this isn't available ready to buy? Yes, space-wise it's getting tight, but it is possible, as a 1 1/8" steerer has a OD of 28.6mm and in my concept I have 28.7mm ID left, i.e. 0.1mm of air (better than nothing ;-). Also, the wall thickness of the adapter will be rather thin at 0.75mm, but this can be resolved by using stainless steel instead of aluminium for the lathe parts.

Check out my drawing here (red = adaptors) and let me know if have missed anything!?

Anyone?

Hey
I would be super thankful if anyone of you guys could take a look into your part bins and find a matching pair of saddle mount shells (?) to rescue a vintage Syntace Moxey suspension seatpost. This is such a rare and nice seatpost it would be a shame if it can't be used anymore just because of these two missing parts which are easy to find on many other older seatposts, too.

Of course I would also pay for a full seatpost if necessary. See the image, I need a pair of these and they should be at least something like 28-30mm diameter when measured the way I did:

Please PM me or email magnusjetski@gmail.com

freewheel

I know that rear brakes are fantastic on wet or steep terrain, but my comparison refers explicitely to the difference between front vs. front+rear on dry flat pavement

I was riding with just a front brake for a long time, and I had this incident some years ago where the brake cable snapped right on a big crossing, luckily I was going not that fast and the car next to me that was taking a turn realized early enough that I cannot slow down, it was actually a nightmare situation, especially considering that the car could also have been a lorry or something.
The next day I was wondering what to do, because the frame had no possibility of adding a rear brake (track frame with carved-out rear bridge).
So, I decided to simply fit a disc fork, build a front wheel with disc hub and rim brake compatible rim, and ended up with two front brakes (left lever = hydraulic disc brake, right lever = classic rim brake), but I actually never ever use the right lever, which is solely there in case the disc brake fails.
In my case, there is no other way of adding a second brake anyway, but this unusual setup was often the starting point for discussions as described in #1

Hi, something that I have been arguing about with people (especially bicycle newbies) for DECADES now, and I am pretty sure about it, but not 100%, so I am happy to hear your well-founded opinions:

In case you want to do a sudden full braking (on dry flat pavement), will it make any (which) difference if you
A) brake solely with a really good front brake (for example a disc brake), carried out in the perfect way, i.e. really hard and with your rear wheel taking off a bit, but without flipping you over the bars
or
B) also using an additional rear brake (not sure what the "perfect way" would be, if your rear wheel takes off it makes no difference anyway! So that would mean you may not brake as hard on your front wheel as in A?)

Happy to hear what you think

Thanks but I need actual measurements - noone riding either of these tyres in 25c or 28c who could quickly take a measure?

Could you please help me, I need to know the height in mm (measured from the top edge of the rim) of either 25-622 or 28-622 Conti Gatorskin (and/or) Grandprix 4seasons (i.e. any Conti with these dark brown crosshatch pattern sidewalls) on a narrow classic 1980s clincher rim 13mm rim like the Campagnolo Omega-V or Mavic Open4CD or the likes, measured with at least 6bars pressure?

I need to know this as I need to order tyres for my gf's bike and she wants them to be as big (comfortable) as possible but the forks allow only just above ~25mm of height.

Thanks for measuring!!!
jetski

how about posting the measurements, ST ctt or ctc, TT, steerer tube

It really hurts seeing the paint and chrome touching that wall bolt!

BUMP - still haven't found anything

Wanted: set of BLB Notorious 38 carbon rims (or maybe wheelset)

PM me please, or post here