I recently purchased a nice new Cinelli 1A stem and am looking to use Nitto M186 "Neat" bars with it:

I am wondering if anyone knows if that is possible? The flattened top sections are what really worry me (though according to Nitto they measure out at 24.0mm) and I fear I might just have to buy them and test them out.

Both are 26.0 and the bike it is going on uses a quill stem so all of that is correct. I am also not planning on converting the bike to 1" threadless or putting adapters in or any of that jibber-jabber and I really don't want to use round bars (my hands prefer flat tops for comfort)

I don't understand your question. You have a 26mm stem and handlebars that are made for a 26mm stem. They were made to go together. The rest of the bar is almost always smaller than the center. This makes it easier to maneuver it into a stem (around all the curves) without scratching the hell out of it. If it makes you feel more confident, I have a Nitto Technomic stem with 26mm head and the Nitto M186 bars. Everything fit together perfectly.

I assume you're asking if there will be a problem threading those bars through the stem, perhaps it would get stuck at the bend. I would guess it's not a problem from what I see. The diameter doesn't look any larger.

You are worried the corners of the flattened part might prevent the bars from fitting into the quill???

Yeah, that's a possibility. Let us know when they come in.

Quill stems are pretty, but they are a pain for changing out bars or if you simply want to change stem length after you've got your bars wrapped pretty.

What's the clamp diameter of that Cinelli stem? Cinelli used to have some unusual clamp diameters that pretty well precluded using anything but a Cinelli bar.

The OP stated that the stem clamp is 26mm. From a quick google look-see, it seems the 1A only comes in 26mm now.

That's a nice bar.

Maybe wrap the bar in blue painter's tape so it doesn't scratch and can be returned?

I had to use a different stem on mine, one that had a cap instead of the clamp. Think it was a Nashbar product, though there are more than just them.

Thanks to all. I am a bit more confident now. I will probably end up buying the bars soon, however I still need to get a new headset and some other parts.

The few times I’ve tried to mount modern, tight-radius bars in stems with wraparound clamps it has varied between a struggle and impossible.
Not saying it HAS to be like that at every instance.
I might try it again if I already have the parts at hand, but I wouldn’t buy a wraparound clamp to go with a modern bar again.

It helps to rotate the stem to negotiate the tight spots - like trying to get a couch into an apartment.

Some bars with flattened areas on the tops have portions that are wider than the stem's clamp diameter. With those, you'd have to use a stem with a removable faceplate or hinged bar clamp, ruling out the Cinelli 1A. My guess is that's kinda what veganbikes was asking about.

Yeah, but that’s true even for old-school large-radius bars.
IME it isn’t always enough for modern tight-radius bars.

Anatomic bars with tight radius like Modolo Anatomics have been with us since before removable face plates.

More importantly, Nitto does a good business in stems nearly identical to the OP's Cinelli. While it is possible that this bar won't work with a quill stem, chances are Nitto wouldn't make their 26.0 bars so they are incompatible with Nitto 26.0 quill stems.

That’s been my experience, too. In fact, I just recently fought with a Soma Highway 1 compact bar and Sutro quill stem for my daughter’s bike. Even with the fairly round curves of the Highway 1, it was still a decent challenge to mount the bar. With more angular tighter-radius bends, it could’ve been a real pain in the rear.

True but companies make incompatible products all the time. Granted I doubt Nitto is going to be that daft but it is possible that is why I asked. You never know?

Thanks again to everyone for the help and continued debate!

bar started out round, was reshaped.. * Newest Carbon flat top required open face stems..

Apex of bend faces the bottom of the stem.. that's why it is narrower .. where the bolt is..
as you feed it through..



..

If I never own another stem with a wrap-around clamp again in my life it will be too soon.

I guess most people don't read most of the comments, so I'll repeat for possible penetration from my first response (post #2), that I have the M189 bar and had no problem fitting it into a Nitto Technomic stem (with a clamp virtually identical to the Cinelli 1A). Both stem and bar are 26mm at the clam area. The bar is 23.3mm elsewhere to give some room for fitting it through the stem clamp, despite the sharp bends and slightly flattened spots. The M189 is heat treated, forged aluminum, not carbon fiber, so conjecture that some carbon fiber bars don't play well with traditional quill stem clamps is irrelevant to the question of whether the M189 will fit the 1A.