Apocaplops

Egad, I found out the hard way my oddball proto-cross frame has a 21.1 quill stem. Is there anyone out there that makes a quill stem - threadless adapter in that size, or at least a stem for 25.4 bars that has some decent length?

As a second thought, it has an odd stem on it with sufficient rise and reach, but it's made for the old MTB bars, quite a bit smaller than the 25.4-26 mm diameter of modern drop bars. Anybody ever make drop bars in that smaller diameter?

T-Mar

21.1mm was the standard for BMX and department stores bicycles. Many of the vintage Japanese drop bars, such as SR and Nitto are 25.4mm. There should be lots of those around. Alternately, it does not not take much effort to sand a 22.2mm stem down to 21.1mm.

jgedwa

Crap. This is a problem with no great solutions.

There still are small diameter stems floating around out there. But they are super-hard to find with long reach.

Could you ream out the stem clamp to 25.4? My LBS will do it for peanuts; if there is enough material there to work with.

You can also replace the fork altogether with one with normal dimensions.

"sand a stem down to 21.1"? Good luck. Do a search and see how many people have managed to pull it off successfully. And see what the ordinarily sanguine Sheldon Brown says about it.

jim

T-Mar

My goof. You're right, sanding down to 21.1mm is too much. I was thinking of sanding 22.2mm down to the french 22.0mm size.

Still, old SR and Nitto bars in 25.4 should be reasonably easy to find.

yohannrjm

I have actually done that (sanded down a 22.2 mm stem to 21.15 mm). It took a long time and some careful work to get down to that width. It 'worked', in that it fit in the steerer tube and I was able to steer the bike with it. However, it scared me to ride that bike with that setup, and so I found a 21.15 stem that worked for me.

Harris Cyclery has a couple of 21.15 mm stems that they sell, but they both are for cruiser type bikes (with rise, and heavy). They also sell a 21.15mm stem extender. I was wondering if that was convertible to a threaded-to-threadless adapter (with a shim, of course), though I've never tried that.

Apocaplops

No no, the old stem that the bike wore had a tiny bar size, much smaller than 25.4.

Anyway, I have an old Schwinn in the garage, and took its old heavy steel quill out. Worked fine, although not quite as high as I had hoped. I may hop down to the LBS sometime to see what they would sharge to ream out the steerer, but I have a hunch it won't be cheap. Too bad, I have a beautiful Technomic stem just sitting here.

yohannrjm

If all you want is to fit standard road handlebars on there, then Harris Cyclery is your friend.

evwxxx

He apparently needs a 21.15 diameter quill stem (in order to use his old forks/headset) with a clamp size less than 25.4 for a drop bar set up. Not an easy thing to find I imagine. Some of the very old steel road bars may have been less than 25.4, but I don't recall seeing any.

jgedwa

Reaming out the steerer is also controversial. Do a search for that on the mechanics forum. It does not seem like it would be all that hard, but people who have actually tried it say it is hard. I have thought about it, but never done it.

Setting aside the height and reach issues (i know, I know...), the simplest and cheapest solution is to dig up an older 21.1 stem. Not at all uncommon. I have two, but I can't spare them.

jim

j. hughes

I have an older MTB that I want to put a taller stem on so that I can use mustache bars.

I measured with calipers and apparently I have one of these 21.1 mm stems. I have found an appropriately sized stem here, however it only fits 25.4 mm handlebars and my Nitto Mustachebars are 26.0 diameter.

Is my only option to get a different set of bars? Does anyone know where I might find a 21.1mm quill stem with a 26.0mm diameter handlebar clamp?

PlatyPius

Keep watching eBay. I saw a couple, but they were sold as soon as they were listed. No one that I know of makes a 21.1/26.0 any longer.

Your best bet might be to sell the Nitto moustache bar and buy a 25.4 diameter one. You shouldn't have any trouble selling the bar you have....

j. hughes

I'm thinking I might go with changing the fork. I would need a new heaset too though, right? Anyone got an extra 26" fork laying around gathering dust you'd let go of for cheap? How do I measure what length steerer tube I need? From where it meets the crown to the top?

akcapbikeforums

I'm looking for a 21.1/.833 quill for my Schwinn Continental resto.

I'd have a hard time putting one of the sturdy, modular BMX stems on my Continental -- these are readily available.

I'd love to find a stem that had good forward reach, without dropping down... more like a Nitto dirt drop.

This is the closest I've found, on ebay, from seller aaabicycle (no affiliation). My Continental is black, so this might not be the end of the world:

NormanF

Sunlite makes high rise 21.1 stems. They are kind to your back if the stock stem won't let you jack the bars up high enough to be comfortable.

Scooper

I had a local machine shop turn down a 22.2mm Velo-Orange threadless stem adapter to 21.1mm for my Super Sport project. I like it because I can change the height since it's a quill adapter, I can change the extension length by just changing the threadless stem without having to take one of the brake levers off the handlebar and slide the bar through the stem clamp, and finally it's not as flexy as a Nitto Technomic or Cinelli quill stem.

Here are (L to R) the original OEM Schwinn stem, the modified 21.1 V-O threadless stem adapter and threadless stem, and the original 22.2 V-O threadless stem adapter.



Here it is on the nearly completed Super Sport.

Noah Scape

Funny this thread should come back up. I have a neighbor that has a metal lathe, and I chatted with him today about dusting it off and turning a Nitto down to a 21.1 for my Sports Tourer. He's retired and a bike nut - he has a great old Raleigh International with those crazy Phil Wood pedals - and I think he's gonna really get after it! I'll let you know how it turns out... no pun intended!

Mr IGH

You guys don't like this 22.1mm stem adapter from Harris:
https://harriscyclery.net/itemdetails.cfm?ID=2119

tatfiend 

What you linked to is strictly a stem riser for raising a 21.1mm stem which is too low. It does not affect stem reach or angle. Also IMO it would look pretty wierd on an old road Schwinn.

Unless worried about authenticity and original looks the Velo Orange stem adapter, turned down, appears to be the most versatile solution as it allows the use of the very wide range of threadless stems which are now available in a wide range of lengths and angles.

Mr IGH

Thanks, didn't notice the difference. My son is taking machining this semester, anyone have a drawing?

Scooper

If you mean a drawing for turning down the Velo-Orange stem adapter from 22.2 to 21.1 on a lathe, I didn't have a drawing. I just took the adapter and the original Schwinn 21.1 stem to the owner of a local machine shop and told him I wanted him to take enough meat off the adapter to make it the same diameter as the Schwinn stem, and he understood exactly what I wanted. The modified stem adapter couldn't have turned out better as far as I'm concerned.

He charged me $20 for the job, but I was happy to pay it.

Mr IGH

I was thinking about making one from scratch...I realize you guys are right, much better to start with something close and modify it.

jgedwa

I have to say, Scooper, that is a pretty slick way to handle this problem. I am not a machinist, but I have some idea what can readily be done, and machining a normal stem with the neck whipping around in the lathe would not be for the faint of heart.

jim