Aheadset

[GaSSoo]

Hi, I bought dual crown fork (28,6mm) for my ebike but old fork has threads and so crown and upper race do not fit.
Want to ask which aheadset should I buy? Do not know if there is aheadset in headtube and I can remove it or not.

 

[amberwolf]

I don't know if your headset is "Aheadset" brand or not (I don't see any markings); you'd have to look at the various Aheadset brand headset images online to see if any match.

But you should be able to use any brand headset that is designed for your headtube and steerer. A handy cribsheet of sizes for headsets at this page
Sheldon Brown's Bicycle Headset Dimension Crib Sheet
that may be useful.

What size was your old threaded steerer? (it's usually stamped into the steerer tube somewhere, otherwise you can measure it's outside diameter (OD).

What is your new steerer's marked OD, if any? (otherwise you'll have to use the measured OD, if that's 28.5mm, which is typical for threadless 1-1/8" steerers)

Some steerers have a larger diameter at the base than the top, so your headset (and headtube) have to be made for that.

If you're going to replace the races already in your headtube, then to know what headset to get for your headtube, you'll need to know the ID of that. It's probably very close to the ID of the inside of the top lip of the upper race, if you can't measure the actual headtube ID. One of your measurements might be measuring this, but is blurry so I can't tell for sure; if it is then its about 31mm.

You also have to know the size of the very bottom of the steerer, so you get a headset with a matching crown race for that.

Depending on what parts you have already with the new threadless fork, you'll need more than just a headset to install it.

Does your new fork have the star nut installed, or do you have one to put in? (and the top cap and tensioning bolt)

Do you have spacers to fill the gap between the cap and the stem, and/or stem and headset?

Also, your handlebar stem from the old threaded one is probably a quill type that goes inside the steerer tube, and won't work with the new steerer, so you'll need a new stem that clamps on the outsde of the new steerer. The stem has to have a clamp for the bars that's the right diameter for the large part in the center of them with the scribed lines on it; this may have a stamped marking with it's OD to help.


Below is a diagram found in an image search for "Threadless steerer" to show you the full stack of parts you need.




Another image from Sheld Brown's bicycle maintenance site

Servicing Bicycle Headsets

types of bicycle headsets (steering bearings; how to rebuild and adjust them

www.sheldonbrown.com

 

[GaSSoo]

New fork have 30mm at bottom. I think inside of frame head tube is cups so I cannot mesure ID of frame. Sorry for blurry photos I can try take new ones.
How can I mesure inside diameter of frame tube when there is cup inside? Do I need remove old cups from frame tube or I can use it?I I have star nut and spacers and handlebar stem with new handlebars as well.

 

[docw009]

Start with the old fork and measure its diameter. It is either a 1" (25.4mm) or 1-1/8" (28.6mm). Your new fork is probably 28.6mm. If the old one is 25.4mm, the frame will probably be too small to convert, but if it is 28.6mm, you can convert it to threadless.

Knock out the old cups using a hammer and screwdriver. Buy a new 28.6mm headset. Press in the new cups. . I have used a long threaded 9/16" rod with nuts as a home made press. When you knock out the old cups, measure their diameter and compare to the cups in the new headset, so you don't try something that won't work.



The headset kit will include the crown race bearing which you must install on the new fork. It will also have an assembly diagram. When you take the headset out of the box, keep the parts lined up in the same order as the diagram.

 

[GaSSoo]

Thank you for helping. Old fork was 28,6mm. New is 28,6mm at top and 30mm at bottom. I try to remove old cups and mesure inside diameter.

 

[Chalo]

That's a totally regular 1-1/8" fork. Your old one measures the same if you remove the crown race. (Crown race press fit is 30.0mm, threaded or threadless.)

 

[docw009]

I've wondered about that Chalo. I no longer swap cups when changing threadless forks, but no need to swap cups between threaded/threadless if both are same diameter?

 

[GaSSoo]

That's a totally regular 1-1/8" fork. Your old one measures the same if you remove the crown race. (Crown race press fit is 30.0mm, threaded or threadless.)

I mesured old one after I removed crown race and it is 28,6mm. new one have at bottom 30mm. I was trying before mesuring to put crown race to new one but no chance.

 

[Chalo]

I mesured old one after I removed crown race and it is 28,6mm.

Well, that's nonstandard then. Was it a hassle to get the crown race all the way down a steer tube the diameter of the press fit?

 

[GaSSoo]

Was it a hassle to get the crown race all the way down a steer tube the diameter of the press fit?

I cannot put it to new one. I should have measured the diameter first before I tried to put it there. My bad.

 

[docw009]

I had that problem on a 1" threaded CAPA RST fork stem. I believe I probably used the wrong crown race, but it also got stuck. I cut a piece of iron pipe to fit over the stem, and used my home made press to push that bearing down. Ever since then, all the crown race bearings fall to the bottom and tap in.

 

[Chalo]

I had that problem on a 1" threaded CAPA RST fork stem.

There are two common crown race diameters for 1" forks: 26.4mm for ISO headsets, and 27.0mm for JIS headsets.

There's only one standard size for 1-1/8" headset crown races, and that's 30.0mm.

 

[docw009]

There are two common crown race diameters for 1" forks: 26.4mm for ISO headsets, and 27.0mm for JIS headsets.

There's only one standard size for 1-1/8" headset crown races, and that's 30.0mm.

That's right. Now I remember. Someone told I needed the 27mm later. But I didn't know that then. I ran a dremel on the inside but I doubt I removed much, I just pushed the sucker in there. It may have split by now,

 

[GaSSoo]

I have little problem. I tried put crown race on new fork but I was stupid and do not mesure it before and now it is stuck and it cannot go down or up. I do not know how to remove it.

 

[calab]

I leave mine on the frame, and reuse it
or I bag the parts and label the bag and the ink wears off and you cant read it. The bag is then hidden at the bottom of the tote box that holds 100 other little tiny ziplock bags of mysterious wonder, ink wiped off bag.

I use a long big flat head screw driver put down into the headset tube to lightly tap the races off the head of the frame. I be sure to have the blade of the flat head along the circumferance to lessen damage to the race, having a smaller contact patch will dent it, using a flat head screwdriver.
Next, Slowly going around the circumferance of the race, light taps, evenly around.
I find the correct position to be in to tap with my body and the frame. You can buy a ParkTool but no need.

To put on I square it all up, block of straight something like wood and lightly tap it on so it stays on, then make sure straight something like wood is straight to the frame so it slides on evenly. I eyeball it on every whack or tap when I put on a new race to the frames headset tube of the frame.

PS
Chalo reminded me of long threaded rod with big ass washers and appropriate nuts, tighten slowly and eyeball it so it square on every twist.

 

[Chalo]

I have little problem. I tried put crown race on new fork but I was stupid and do not mesure it before and now it is stuck and it cannot go down or up. I do not know how to remove it.

Punch or pry it from the bottom, switching positions around the fork steerer as you go. It will come off. When/if you reinstall it (or another 1-1/8" crown race), lightly grease the seat and the inside of the race before driving it down.

I think you may be having unnecessary problems due to limited skills and/or tools for the job, and a bike shop may not have to spend any real time or effort to get you sorted out.

 

[GaSSoo]

Ok so I removed that crown race with effort and hammer but it is done.
I messure ID of frame head tube and it is 44mm.
Will this headset fit?

 

[Chalo]

Yes, that headset will work. Note that it's customary to use a headset cup press to install the cups, and a crown race slide hammer to install the crown race. There are other ways to do it, but also ways to screw it up if you improvise.

 

[GaSSoo]

Thank you. I prepared for it to install cups and crown race. I hope everything will be ok.

 

[GaSSoo]

So I made it. It was little dificult but I like to try new things. So thank you guys for help.

 

[Chalo]

Whoa, I thought you had a bike. My guess is that the long fork will make the steering qualities of your, um, thing, kinda random. I'd love to hear how it compares to before, handling wise.

 

[GaSSoo]

Yes it is a e-bike. It is much better now. It is more comfortable thanks to better suspension and more controllable thanks to wider handlebars. This is how it looks like before.