Bike Forums - Threaded stem run like a threadless

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- - Threaded stem run like a threadless (https://www.bikeforums.net/bicycle-mechanics/1306233-threaded-stem-run-like-threadless.html)

Quote:

Originally Posted by Kontact (Post 23477686)

I would say you were optimistic and cavalier with your safety. Steerer threads are normally reinforced on the outside by the locked portions of the upper headset and the quill inserted into them. You have managed to take a steerer - which is essentially full of spiral cut, sharp bottomed stress risers, create two compression edges on them at the top of the HS and bottom of the stem, removed any internal reinforcement a quill brings, and then put extra forces on the part being pinched by the stem.

People always seem pretty pleased to report the super dangerous mechanical things they've done, but maybe you should hide this sort of bad decision and just thank God it didn't end badly.

Well it hasn't ended yet, badly or otherwise. Your concerns are valid, and I certainly would not have built it this way for a customer, and I probably should not have encouraged the OP.
Now that the parts shortages have corrected somewhat, the plan is to cut the steer tube and insert a quill adapter. My preference would have been to go threadless from the start, but those parts were simply not available from my sources.
https://cimg6.ibsrv.net/gimg/bikefor...6062bbac5f.jpg

Quote:

Originally Posted by srinath.the.man (Post 23477796)

Steerer tube to a bicycle is called stem in motorcycles. It's called steering stem to be precise.

This is not a motorcycle forum, it does not use motorcycle standards and comparison is broadly irrelevant and confusing. For 140 years pedal cycles and motorcycles have evolved along divergent paths, the terms and technology are different. There are motorcyclists here, but they use pedal cycle terms and discuss pedal cycle technology because that's the forum's purpose. If you want a "bicycles for motorcycle mechanics" forum I suggest you start one on Facebook. OTOH if you want to discuss bicycles please use the appropriate terminology and try to keep the discussion on-topic.

Quote:

Originally Posted by Andrew R Stewart (Post 23477776)

So far this thread has had more wrong/unsafe info than most threads do:) Andy

I was going to comment further but I'm suspect that I'm still on the brink of banishment so I'll refrain.

Y'all have a nice day
Charlie

A threaded steerer tube sticking up 2" above the neck tube is inherently subject to get damage even if a quill style stem is inserted and "reinforced". So The right steerer tube (its original) or threadless it is.

Quote:

Originally Posted by srinath.the.man (Post 23477796)

Steerer tube to a bicycle is called stem in motorcycles. It's called steering stem to be precise.

Yeah I get that now. But you were using incorrect and totally confusing words in this bicycle forum. And you took very long to clarify it.

Quote:

Originally Posted by srinath.the.man (Post 23477809)

I get it. Threads cause a starting point for a crack and this will not bend and give you any warning, it will just snap like a pretzel. I get it, I am steering away from it (no pun intended :lol:

Are you going to do what was suggested by BICYCLE (not motorcycle) experts in the very early part of this thread and repeated - using an inexpensive and readily available threaded to threadless converter? Actually designed for the purpose? A very simple, safe and foolproof conversion? I haven't seen acknowledgement of that yet and you've wasted far more time in your confusing diversions than a conversion would have taken.

Then I see this:

Quote:

Originally Posted by srinath.the.man (Post 23477826)

The more I think about this, the better option is to do what I have done before on my cheater chopper (motorcycle).
There is enough room between the treaded part and the stem for me to run an inner tube as a spacer. Then I'll use a long bolt ~8mm and 2 large washers and bolt it top to bottom. That serves the same purpose as a quill type insert, but instead of friction load transfer to the steerer tube and then the neck it actually bolts them together. That way even if the steerer tube cracks at the threads the bolt will keep it from coming apart. Rubber will avoid loading 1 spot hard too. Not gonna win any beauty contests, but I'll post the result if I ever get around to that way. I have various parts I dont even know about lying here and there. Lets see.

Fercrissakes man. Just do it right! Easier, safer, foolproof (now I'm seeing the value of that word)

Quote:

Originally Posted by srinath.the.man (Post 23478022)

Cutting the threaded STEER TUBE so it isn't too long for the frame's HEAD TUBE isn't a bad idea as long as there's still enough threads to get the top bearings adjusted properly. And, although 2" is a lot, they make, and many bicycles use, spacers for that purpose.

https://cimg1.ibsrv.net/gimg/bikefor...7ba3083cc1.png

Here's one of a million sources; Rene Herse Threaded Headset Spacers (1 inch) – Rene Herse Cycles

This link might help you to undersand the difference between a bicycle steering/bearing system and what you're used to on a motorcycle.
Threaded Headset Basics - Velo Orange

Not looking to buy more parts. Let me see what will fit/work.

Quote:

Originally Posted by srinath.the.man (Post 23478302)

Not looking to buy more parts. Let me see what will fit/work.

Buying parts from a reputable dealer of bicycle parts (like your local shop or an online bike shop not random third party sites) is a lot cheaper than hospital bills.