Classic & Vintage - Cinelli stem compatibility

Hi all,

I am looking for a stem to replace a 26.4 Cinelli 1R. I'd like to replace it with an X/A, but the vast majority of those available for a reasonable price are 26.0. Is it possible to use a 26.0 stem with a 26.4 bar? Rationally it seems like 0.4mm wouldn't be that much for the stem to spread and still be usable.

Do any of you know if it would work?

Thanks

-Steve

I wouldn't do it.

Not (safely) possible with a traditional quill stem.

One can get away with it on some of the modern (threadless, mainly) stems w/two-part clamps, but strength comes to question with these setups.

-Kurt

I've personally taken 26.4 bars off a stem that was a 26.0 so yes it's possible to install one on the other. It is difficult requiring a fair bit of prying on the stem to prevent completely destroying the clamp area of the bar. I will not recommend doing it though, you never know what may cause a stress crack to develop and over time cause a failure.

I had a 3ttt stem crack that some dolt put on a cinelli bar.

Don't do it.

What length and color do you want? Are you set on an XA? Someone may be able to help.

Give me a minute here, and I'll have a photo here of what happens when one tries forcing a 26.4 into a 26.0 stem...not pretty.

EDIT:

http://www.jaysmarine.com/giro_groundup.jpg

Glad to say I wasn't the one trying it. Whoever did obviously never succeeded either (unless you consider ripping up the bar a success).

-Kurt

It can also cause your bar to snap at the stem when you're pulling on it hard. Aluminum doesn't like to be crushed.
Unless you have a deathwish, don't do it.

Unless you have a deathwish, don't do it.

Didn't we have a thread here about 3 years ago about every single way one could booby trap a bike so that any thief who stole it would be lucky to emerge alive? Remind me to put this on the list :eek:

;)

-Kurt

Ok ok ok... stop panicking. I won't do it the fudge way.

Is there anyone out there with a 26.4 stem that they would be willing to part with? A silver X/A of about 100mm would be ideal, and I dislike the aethetics of the 1A, but at this point, I just want something that will clamp reliably enough to allow me to keep using my cinelli LA84 tt bars. The 1R just doesn't put out enough clamp force to deal with the torque.

-Steve

A Black 130 and you'd be in business.

Ok ok ok... stop panicking. I won't do it the fudge way.

Is there anyone out there with a 26.4 stem that they would be willing to part with? A silver X/A of about 100mm would be ideal, and I dislike the aethetics of the 1A, but at this point, I just want something that will clamp reliably enough to allow me to keep using my cinelli LA84 tt bars. The 1R just doesn't put out enough clamp force to deal with the torque.

-Steve

I don't understand your problems with the 1R. I have a 1R on my triplet, as well as on my trike, both with wide bars to offer extra leverage needed to handle these two odd applications (with correspondingly higher torque than anything that you ever encounter with bulls horn bars.) The 1R stems clamps perfectly. Have you slathered grease everywhere? If the 1R stem is not clamping down properly, there are a few relatively easy fixes: take it all apart and replace the wedge with a new one, then grease it all up and clamp the bars in the correct position the first try. If this doesn't work, I would check the front of the stem, where the black Cinelli plastic logo is, to see if there aren't perhaps little cracks. I have seen quite a few 1R stems crack across the front.

The primary cause of trouble is the fact that the bolt for the hidden clamp mechanism is alloy, and was in poor condition when I got it. It has since gotten worse, and now is nearly stripped. I would be just fine if I could find a stainless steel bolt in the same archaic size and pitch as the alloy one.

In lieu of that, I would just assume replace the 1R with an alternative clamp design that puts pressure on the bars in more than one small patch. If you consider the design, only the small area of the wedge is putting pressure on the bars, whereas a design such as the X/A puts force on the bars over the whole area of the clamp. It is a technically superior design, despite the fact that the 1R is clearly the more artistic solution.

The bull horn bars generate a large amount of torque due to the fact that the bars extend forward a good ways from the stem, and pressure on the tips of the bull horns causes the bars to rotate forward.

-Steve

PS Again, if anyone is in possession of a silver 26.4 1" stem around 10cm in length, please let me know...

The primary cause of trouble is the fact that the bolt for the hidden clamp mechanism is alloy, and was in poor condition when I got it. It has since gotten worse, and now is nearly stripped. I would be just fine if I could find a stainless steel bolt in the same archaic size and pitch as the alloy one.

Had the same problem with the 1R I mounted to my Trek 610. Somehow, I was able to use an imperial-sized allen key and some judicious, slow spinning to get it tight. Your mileage may vary.

Careful with NOS bolts too - they just as easily slip and strip.

Alternately, find a beat 1R on eBay with a decent bolt - something missing the binder, perhaps. Should work for you.

-Kurt

Hi all,

I am looking for a stem to replace a 26.4 Cinelli 1R. I'd like to replace it with an X/A, but the vast majority of those available for a reasonable price are 26.0. Is it possible to use a 26.0 stem with a 26.4 bar? Rationally it seems like 0.4mm wouldn't be that much for the stem to spread and still be usable.

Do any of you know if it would work?

Thanks

-Steve

If you really can't find a 26.4 stem in the extension you want, mod a 26.0 to 26.4 with a flapper wheel (I'll describe in a sec).

Flapper wheel, as I've always done it: 3/8 metal dowel or drill bit with a long strip of cloth backed sandpaper wrapped around it. 100 grit is plenty coarse enough. Chuck it in your drill motor, wind it up, shove it in the hole, and sand away. Measure before you start, and check it often as you go--on alloy it's quicker than you might think.

I recommend this on the assumption that Cinelli is still using the same molds to make 26.0 as they used for 26.4 (i.e., the material is still there). If anyone knows differently, speak up!

Good luck!

Can someone post pics of what a 1R, XA, etc. stem looks like, and what are the pinch bolt sizes? I think I have one of each, with matching bars, but only one bolt. I found SS bolts for one of them at a specialty fastener shop, then realized they each take a different sized bolt, and the shop didn't have the size needed for the other stem (7mm?).

Can someone post pics of what a 1R, XA, etc. stem looks like, and what are the pinch bolt sizes? I think I have one of each, with matching bars, but only one bolt. I found SS bolts for one of them at a specialty fastener shop, then realized they each take a different sized bolt, and the shop didn't have the size needed for the other stem (7mm?).

The following website has the most complete rundown of Cinelli bars and stems that I know of:

http://www.43bikes.com/cinelli-bars-stems.html (http://www.43bikes.com/cinelli-bars-stems.html)

The 7mm (Diameter, 6mm hex head) bolt that you mentioned is for the 1R hidden clamp stem. It is an unusual size complemented by freakishly fine threads. The X/A, on the other hand, takes a more common bolt size, according to my understanding. Hope that helps.

-Steve

universal cycles has a few nos cinelli 26.4 stems:
http://www.universalcycles.com/shopping/index.php?category=3432

they also have a few nos cinelli 26.4 bars for a reasonable price:
http://www.universalcycles.com/shopping/index.php?category=3433

Can someone post pics of what a 1R, XA, etc. stem looks like, and what are the pinch bolt sizes? I think I have one of each, with matching bars, but only one bolt. I found SS bolts for one of them at a specialty fastener shop, then realized they each take a different sized bolt, and the shop didn't have the size needed for the other stem (7mm?).

Are you referring to thread diameter? All hex fittings on cinelli 1R and 1A are 6mm. Only the pre-1972 1A had 7mm allen fittings for the stem binder bolt.

I have a nice 1A in 95mm. Flying C logo. It'll save you from modifying something. PM me.

Are you referring to thread diameter? All hex fittings on cinelli 1R and 1A are 6mm. Only the pre-1972 1A had 7mm allen fittings for the stem binder bolt.

From the pics it looks like I have an XA (with a conical expander) and a 1A, one is 26.0 the other is 26.4. I'll check the bolts again - I was sure they didn't interchange, but that's probably just my bad memory. There's also a TTT stem in the parts box to confuse me even more (maybe that was the stem I can't find a bolt for???).

Thanks for the link to the 43bikes website - what a neat place to look through!