31.8 Handlebars with 1" steering tube
 

I have an old 80s hard tail MTB with old bullmoose bars that I use for touring up to a few hundred miles at this point. I have the bullmoose bars high by way of a riser/extender to give an upright ride but even though the height is right, I would like them an inch or two closer to me horizontally. I think the back sweep is up to 25 degrees if I had to estimate.

I am looking at switching to the Soma's Dream riser bars and some new stem to get the bars closer to me. But the clamp area is 31.8 mm and it seems it is hard to find a stem with a 31.8 clamp to fir a 1" steerer tube. Soma is suggesting their Nitto UI-12 but I am having trouble picturing it. And I am not clear about the angle choices: 72 or 90.

I do like the Nitto MT-10 long quill stem but the clamp size wouldn't work.

Any suggestions or pictures?

The Origin8 Pro Fit ATB stem is available in 90mm and 110mm. It is what I use on my 520 currently.
https://cimg9.ibsrv.net/gimg/bikefor...6663607527.jpg

Another suggestion is to use a 1'' quill stem adaptor that takes any 1-1/8 stem. Plenty of inexpensive 1-1/8 stems on the market, all lengths and degrees of rise
Here's a link to an adaptor: https://velo-orange.com/collections/...s-stem-adaptor

you could try something out of the box, like checking ebay! just enter "quill stem 31.8" and like magic all these 1" quill stems show up that take 31.8" bars. first try i got 55 hits.

maybe something like this would work?

IXS Adjustable Quill Stem Quill 25.4mm Adj. 70~130° 31.8mm 85mm 100mm 115mm

https://www.ebay.com/itm/IXS-Adjusta...JrU47n6fIjjl7w

https://www.ebay.com/itm/ACCENT-Eagl...zonNvdDtOJnekg

be sure to check the ad text carefully.....not always clear about the measurement....is it the outer diameter of the steer tube, or the inner diameter measurement...

That ^^^ is a good one that I've used in the past, very well made. My favorite quill adapter is the Nitto MTC-04.

Dimension is another good, fairly tall 1" to 1 1/8" quill adaptor. It provides 118 mm of rise to top of riser at minimum insertion. Combined with the pictured stem it brings my bar tops 2" higher than the saddle ...

https://cimg6.ibsrv.net/gimg/bikefor...b8a245221d.jpg

Not familiar with the product but those sound like road stems; a 90 degree bend being a later road-type offering (slight rise when viewed in profile due to the right-angle stem being in a slanted steerer tube) while the 72 degree would be your typical flat/level stem (also viewed in profile). The latter type is frequently referred to as a "negative" number stem, like a -18 degree instead of 72 degree; 18 being the complement of 72 to total 90. Same thing, different description.

Thank you - I understand now. Here's a link to the Nitto UI-12 I referred to: https://www.somafabshop.com/shop/pro...0?category=813

I have seen older mountain bikes like mine usually with a stem with an angle greater than 90 (based on what I understand from your writing). That seems appropriate for me since I want an upright ride. But most seem to extend forward way too much and of course offering a clamp size too small for a 31.8 bar. That's why I mentioned the Nitto MT-10 long quill stem. It seems to have an angle greater than 90 but extends forward only minimally. I also like it's simplicity, like it's smooth and in one piece instead of a riser and stem separated like on modern bikes, especially for an old MTB.

My bike is closest to a 1980-something Schwinn High Sierra if it has any bearing, but it's actually some kind of Scott model I can't find.

@nomadmax That quill adapter, Nitto MTC-04, is beautiful.

If the stem @katsup posted above is not tall enough or the right reach for you, you might have to cobble something up from a quill adapter and a threadless stem to fit your bar, as others have recommended. While I have no 31.8 bars in my fleet I use quill adapters and threadless riser stems on a couple of bikes with another in the works and they suit me fine. The do look kinda clunky but who cares if you're comfy? Stems that slope upward towards the bar, whether a quill or a threadless stem, are generally referred to as riser stems and should not be confused with stem raisers.

Stem raiser or extender.
https://www.sefiles.net/images/libra...r-263069-1.jpg

You might have to use a combination of hardware to achieve your goal, depending on the lift you want; a quill adaptor in your steerer tube, a stem raiser on that and the right threadless stem with the angle and bar clamp size you require. It might get complicated.