[Closed] Flipping a drop stem for taller riders - unsafe?

It'll be fine, just go for it.

It is designed to clamp a length of metal to another...it'll work either way up.

Also where are you? Greenrig Cycles had Renthal bars in with plenty with various rise - definitely had a couple 40mm risers...

You can get some shorter high rise stems - see https://www.tredz.co.uk/.XLC-Comp-25-4mm-35deg-Stem-ST-M15-_126737.htm

It is designed to clamp a length of metal to another…it’ll work either way up.

Exactly.

It's a riser stem flipped upside down. All you'd be doing is putting it on normally.

I've done exactly this on road bikes, when I've wanted an upright position for touring and suchlike. It works fine but you may need to tweak your gear indexing.

When used normally the bolts are predominantly in shear with some tension load, so the load is shared between the stem and the plate. but when flipped a larger proportion of the load is going to be placed into the faceplate, also putting the bolts in tension. Due to the design of the stem, this change is much larger than flipping a conventional stem. Saying all that, by flipping the stem and easing the cockpit, less of your weight will be going through the bars, so maybe it balances out…?

My only reservation on all the above is that you seem to be scraping the eBay barrel for examples.

Some of those designs look awful and their specs are solely in Chinese. Spidey sense is tingling.

with a reputable brand I'd have no issue doing it.

Example number 3 ...... I'd struggle to fit to my bike even right ways up even with a brand name on it..... As an eBay special I'd scroll on by.

Example number 3 …… I’d struggle to fit to my bike even right ways up even with a brand name on it….. As an eBay special I’d scroll on by.
It's a Syntace, probably one of if not 'the' best made stems out there.

Problem is with the shorter stem lengths your not gaining that much with a 12 degree stem, there are a few 10 degree stems out there that would give you almost as much rise (e.g. Renthal Duo).
A set of Answer Pro Taper 800's in 75mm rise would give you more rise but they are pretty hrd to find, or Spank did a high rise set as well. Appreciate that these might not be available wherever you are located.

Stevet1

It’s a Syntace, probably one of if not ‘the’ best made stems out there.

I'm a happy Syntace owner, but that looks like a Syntace but has no Syntace logo. I'd be wary.

How can it matter? You put all manner of different forces through a stem, depending on what you’re doing with a bike.

When used normally the bolts are predominantly in shear with some tension load, so the load is shared between the stem and the plate. but when flipped a larger proportion of the load is going to be placed into the faceplate, also putting the bolts in tension

As with nearly all bolted joints you are rellying on the friction generated between the stem and bars, by the bolt tension, to resist any applied loading. This is because bolts are only about 60% strong in shear as they are in tension and any cyclic loading can fail them at loads well below their shear strength.

The bolts will always be predominatly in tension so flipping the stem will not make any difference.

The bolts will always be predominatly in tension so flipping the stem will not make any difference.

Exactly. The downward force on the bars will actually be converted to a tensile loading on the bolts because the bars will try to force the faceplate away from the stem at 90 degrees to the bolts' axis. The bolts won't have any sheer forces acting on them, they'll be purely under tension.

Have you thought about working on your flexibility before spending money?

@DickBarton @Stevet1 @trail_rat I'm in a mountain city in SW China, the bike shops here are Giant, Merida or Decathlon. I haven't seen any independents. Luxury branded import components are running out of stock here. Most riders are roadies so standard gear is still available (We can luckily get Shimano/KMC drivetrain components still)

@munrobiker really long legs, shot up when young, got the curved lower spine to go with it (scoliosis) so flexibility is limited unfortunately. Still my Marin SQ3 does appear to have a really low front end even with a 160mm SR Suntour Durolux EQ fitted. I have an 80mm 7deg Dabomb stem on, with the old Marin low riser. Website is stating specs for the bar that aren't what I have. Upreach and sweep definitely feel a lot less than the 28mm, 9/5deg on the website now.

@honourablegeorge Like in BSG, in China there are many copies 🙂

Specialized do some quite tidy adjustable stems (the Comp I think). Not heavy and you wouldn't know it was an adjustable.

A 12° will adjust up to 16° with the supplied shims. Would be my first choice.

The Syntace website lists the FlatForce stem as FlipFlop compatible

https://www.syntace.com/en_GB/products/stems/mountain-bike/2988/flatforce-44

@qwerty nice find. It's £89 here.

But I also just found it only has a very slim 25mm stack height and, since it's not built like a bmx stem, I have some reservations about the risk to my steerer tube. Shame, as it has more length options (55/88mm) than the other "similarly shaped" stems I've found herr (40-50mm) that'll only cost £9-10.

I'm eyeing up some 30mm rise Spank 777FR Bearclaw bars and hoping this time the seller will actually have the stock.

@mrdestructo this website helps you see the difference weird stems have against your current set up:

http://yojimg.net/bike/web_tools/stem.php

Where have you seen it for £89? I might be interested in a 44mm - ignore this, I just realised that your in China!

@qwerty thanks. Used that before I changed my forks. Couldn't find it again. It'll help a lot. Hopefully it also covers grip position (see below)

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MY EYES!!!

I have to go out and set up my drive train tomorrow in the rain after changing spider/chainring/chain. I've dropped the front end with a bar that has far less sweep than the last one. I'll take a tape measure and pen and paper and note where my grips are now. I have this feeling that the last bars had so much sweep that when I climbed steep mountain roads I was injuring my lower spine area.

@13thfloormonk no specialized gear on the usual shopping sites here. It's a bit like Marin, just one onli e seller in the country. I found searching online there is one Specialized branded store in my city. About 35km away..... I do have to go there at some point actually. Just found out whilst searching that the staff help locals by running offroad rides in the opposite direction from their store.

i do the opposite to get a good position racing. Run my stems dropped. Should be fine, in general they are reversible, they used to be quoted as +/- 7deg or whatever.

What about a dmr defy?

It looks like the stems you have pictured up there but the other way up

https://www.dmrbikes.com/Catalogue/Components/Stems/Defy35

The Hope AM comes in a 20 degree rise in 50 & 70mm lengths.

I reckon you’ll be ok. XC riders have been flipping their stems the other way for years. As long as it’s a decent stem I’d do it.

Plenty of stems come with reversable/rotationally symetrical Graphics, which i always took as an incication they expected it.

compare the length and chunkyness of a stem to the length and chunkyness (wall thickness) of the bar its attached to? Itl be fine. snapping a stem or ripping a faceplate off a stem isnt a failiure ive heard of

Have you thought about working on your flexibility before spending money?

oooof

I always want to suggest a trials stem on these threads. How does 180mm 30° sound? Totally inappropriate probably.

I fitted a shorter rise bar, went out between the rains and did my lower back in.

I think with fitting a longer fork I am bringing the grips too close to myself.

I "may" need an 80-90mm drop stem, correct way up (down! 😂). The website with the measurements didn't really do grip position. Perhaps the sweep of my bars has something to do with it too. and a really high rise bar to stretch the reach out. The Marin SQ does have a really short reach and getting a longer fork reduces it further obviously, particulary since I'm lanky.

There's a seller out here with one pair of brown coloured NS bikes Proof 25.4mm HI bars (85mm at grips) for £61. The sweep seems excessive though at 10deg.

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My only reservation on all the above is that you seem to be scraping the eBay barrel for examples.

Some of those designs look awful and their specs are solely in Chinese. Spidey sense is tingling.

with a reputable brand I’d have no issue doing it.

This +1

I'd have zero qualms with a reputable stem, it's how they were made for decades before 29ers came along.

But it's one of those parts I'd never buy a cheap generic one. I quite happily ran "Chinese" carbon forks, but stems and bars just seem to fail with alarming frequency. Particularly fashionable sizes, there was a spate on a local facebook riding group of everyone buying the same super short stems, then a few months later they all cracked.