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Cinelli Stem Diameter Bummer

9K views 23 replies 10 participants last post by  Fredrico 
#1 ·
I've been swapping out a lot of stem/bars to get just the right fit and feel I want on my 89/90 7-Eleven Merckx. I did not realize that Cinelli stems (and presumably) bars came in both 26.0 and 26.4. Up till now I must have just gotten lucky and every bar/stem combo I've tried worked just fine.

I've been super busy lately with no time to work on the bike. Since all it really needed was a bar/stem swap and fresh wrap of tape I figured the LBS would fit the bill as I'm not the best bar taper anyway. So I took my complete bike with 110 stem and 42 wide bars to the LBS. Took along my new to me 120 stem and 44 bars. AND my finishing touch a red spacer for the stem. Can't have a black spacer on a red/green bike now can we? I also had them put frame saver in the frame which obviously required a bit of tear down.

I pick up the bike and it looks great, shifts fantastic and the stem bar combo is just what I had hoped for. Problem is there is no red spacer on the XA stem. The mechanic said it would not fit. I was perplexed but the bars are plenty tight with no slippage. Rode it twice and decided to check for myself. Sure enough if I slightly pry open the clamp area and fit the spacer in, it won't tighten down enough to keep the bars from rotating.

So I must have a 26.0 stem and 26.4 bars, right? The bike is not may daily ride so I want it to be perfect. We all get that, no?

Any concerns riding it without that spacer while I look for a new stem or new bars? Any guess on which I am more likely to find? The stem is in super nice shape and the visible part of the bars are darn nice. Feeling kind of bummed out. I'm wanting 66-Campione Del Mondo bars.

120 stems seem to be on the rare side in decent shape.
 
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#2 ·
did you mean 25.4 and 26, else i will have to goggle some.... I do not seem to recall 26.4, such as my memory is anymore....

Anyway, perhaps useful. I have a Ti 26mm quill with 25.4mm bars and it took a piece of fine black oxide sandpaper shimming to make it stay put for sprinting....
 
#4 ·
Make a new red spacer, fabricate it a thickness that allows it to be tight enough out of something... there has to be enough plastic someplace to choose from. Adjust thickness accordingly of the material ??

Good luck, and of course with no picture of this bike, it probably does not exist.. hint hint.. ;)
 
#5 ·
Get some calipers and measure things. It's the only way you'll know for sure.

And if the stem and bars aren't the same you won't have good contact all the way around the clamp. Try getting a piece of aluminum foil and see if it will slip into any gaps.
 
#7 · (Edited)
Would the stem measurement be taken with no tension on the binder bolt in its relaxed state? I've got some crappy Harbor Freight digital calipers. Wondering if they will be accurate to the .4mm at the very least they should tell me if one is "different" than the others. I have 110 XA and 1A stems and 64-42, 66-42 bars all that work together properly (with spacer on XA stem).

To complicate matters there seems to be a XE stem that looks like XA stem from the outside but where it binds in the steerer tube it has a wedge not an expanding cone sort of set up. All the XE stems I have seen are 26.0.

I'm looking to accomplish something like this:
Bicycle frame Sports uniform Bicycles--Equipment and supplies Bicycle tire Sportswear


Bicycle frame Bicycle tire Tire Bicycle wheel rim Bicycle fork
 
#6 · (Edited)
From my limited research....I am by no means a bike historian....it seems that while most Italian bars/stems were 26.0, Cinelli was 26.4 until the mid 90s when perhaps TTT bought them and changed things to the more "standard" 26.0. I can find plenty of stems made by Cinelli both 26.0 and 26.4. I can't seem to find proof, by searching, that the Champion Del Mondo bars came in both sizes. I'm after a Cinelli 66-44 bar and 120 stem. Don't really care what the size is as long as they work.

I must be crazy posting I the vintage section without pix, what was I thinking? Here it is not quite how I want it. I've since got the proper fork stickers (Columbus/Merckx) and proper Cinelli white tape with red finish and Cinelli logo black over it to make it look quite like an authentic 7-eleven race bike. Updated with modern 11s drive train. Posts elsewhere on my quest to make Ultrashift (chorus/record) bodies with Athena alloy levers. Labor of love and money pit at this point. But I truly love it. But here it has 110 stem and 42 wide bars in this set of pix but does have the red spacer. Also has a silver CKing headset now.

To be clear my current set up 120 XA stem and 66-44 bars has no spacer at all in the stem. The stem clamp had to touch itself to tighten enough. With the spacer it will not hold the bars in place.

Bicycle frame Bicycle tire Tire Bicycle wheel rim Bicycle fork


Bicycle frame Red White Bicycle accessory Line


Bicycle tire Bicycle frame Tire Wheel Bicycle wheel rim


Bicycle wheel rim Bicycle tire Automotive tire Rim Red
 
#9 ·
Good to know about HF calipers. They are fine for wood working.

The real bummer here is I am so short on free time at the moment. I'd really like to ride the bike while the weather is nice and make it perfect later. Was hoping the LBS would solve my time issue, but not their fault the parts don't mate up.

Since the tape is fresh, only two rides, I really don't want to unwarp and remove one side (again time issues). Cable/housing lengths will probably see me loosening up brakes and derailleurs too. At that point I have gained nothing but a lighter wallet with the LBS work.

I think I'll start by measuring the currently installed 66-44 bars in place and see how the compare to the 64-42 and 66-42 as well as my 110 XA and 110 1A stems.

I so wish I had test fitted the current bar/stem upon arrival from the various ebay sellers, but I had no idea at the time about 26.4 vs 26.0. I might just bite the bullet and unwrap the bars, take the levers off and try all combos out. The 120 stem length is more important at this time than the 44 width. I do like the 66 drop over the 64.
 
#10 ·
So I measured all but the interior diameter of the 120 stem (still connected to bars). I took a couple of measurements on each.

Current 66-44 bars that need spacer removed on 120 stem:
26.34, 26.33, 26.36

Original 66-42 bars that worked fine with XA/1A 110 stem:
26.38, 26.45, 26.23

110 XA stem:
26.26, 26.29, 26.37

The two bars and the 110 stem are obviously of the 26.4 variety, no? If the only choices for the stem I could not measure without taking the levers/bars apart are 26.0 and 26.4 it almost has to be 26.4. How would a 26.3-ish peg fit in a 26.0 hole, right?
 
#11 ·
Looks like everything you measured is 26.4, right?

I take it that the spacer goes round the bars where the stem clamps?

If the spacer won't fit I'd say the bars and stem match. 26/26 or 26.4/26.4?
Wouldn't the spacer be there to enable the bars to work with a larger stem? I could imagine a spacer allowing 26.0 bars to work with a 26.4 stem.

I'm in the US and used to working with inches.
The problem here is that the 0.4mm difference is only .0156" (1/64"); that's probably smaller than the width of the period at the end of this sentence. (Oops, depending on your display!)
So I imagine that a 26.0 clamp could easily be opened up enough to accept 26.4 bars. The clamp gap would be bigger than usual and if you looked closely you could see the clamp only contacting the bars at a couple of places, but it would probably work.
 
#12 ·
Randy99CL, this is the retro section or I would not be worrying about this. This spacer is unique to the Cinelli XA stem and is available in multiple colors. It has nothing to do with the bar/stem interface around the bars. It is above the bolt, between the gap, below the bars.

Here you can see it without spacer and aluminum parts touching each other above the bolt that tightens the bars.
Electronic device Bicycle accessory Technology Electronics Wire


In this picture you can see the red spacer in place on my 110 stem.
Bicycle frame Red White Bicycle accessory Line


When the spacer is present on the 120 stem the spacer prevents that gap from closing enough to hold the stem in place. It seems to be functional, but I want that red spacer present....just because.
 
#14 ·
What you call a spacer, looks like a little cosmetic doo-dad to me. It seems that few would ever notice it there, at all. If you feel deadset on using one, maybe cut yourself a shim out of a beer can. Pry the clamp open a bit and slip your shim between your bars and clamp.
 
#15 ·
At this point I am racking my brain on why it is the way it is? Bars are obviously 26.4.

If the bars are 26.4 and the stem is 26.4 there should be no issue. If the bars are 26.4 and the stem is 26.0 it should have to be widened slightly to fit, so if anything the spacer would float around once bars tight. I've put the spacer in and compressed it so much the rubber squished out of the sides and still bars move freely.
 
#17 ·
Yep, that pic shows that there's no room for the spacer. Looks like the stem is (possibly) a little bigger than 26.4 and you've measured the bars to be undersized.

It's hard to imagine any use for the spacer other than a flash of color. Are the different colors all the same thickness?

Is Cinelli anal enough to use that spacer to keep the clamp gap even? In your picture (without the spacer) it shows that the gap is pinched closed at the end and that flexes the clamp and makes it out-of-round. But how could that possibly matter??

They went to some trouble and expense to make those spacers.
If you haven't, I'd google the hell out of it to find out why that spacer is there.
 
#22 ·
Problem solved for ~$50 and time that I originally did not have/make. Got a replacement 120 stem in great condition. Fit the bars perfectly. BTW a Cinelli "expert" told me those bars were only EVER made in 26.4. Guess they stopped making that model before the mid-90s move from 26.4 to 26.0. Still not sure why the original stem did not work...guess it does not matter at this point.

New tape on the way, but making due with reuse of old tape with just a couple of rides in it. Red spacer in place and no coke can makes me happy. Now if barfly would make a garmin mount in a smaller size so I did not have an ugly black spacer I'd be all smiles.
 
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