Cinelli 1R bar clamp bolt

[Norman H]

M7 X 1mm cap head screws are readily available. If and when the existing M7 X 0.75mm screw fails you'd have nothing to loose by drilling out the female threaded part and fitting an M7 X 1mm Helicoil. The Helicoil thread should be stronger than the original fine thread.

[531colin]

M7 X 1mm cap head screws are readily available. If and when the existing M7 X 0.75mm screw fails you'd have nothing to loose by drilling out the female threaded part and fitting an M7 X 1mm Helicoil. The Helicoil thread should be stronger than the original fine thread.

Just on that note; is the M7 x 0.75 thread cut directly into the alloy stem, or is there a steel insert of some sort?

[Norman H]

I suspect it will be cut directly into the alloy. As I understand it best practice is to use a steel thread insert but cost considerations usually means that this isn't the case. I'm sure Brucey would have an opinion.

[slowster]

Just on that note; is the M7 x 0.75 thread cut directly into the alloy stem, or is there a steel insert of some sort?

Photograph of the parts from here:
https://www.bikeforums.net/classic-vint ... -stem.html

[Jdsk]

Thankyou.

And the screw of interest is the one going into that receiver with the angled face?

Jonathan

[Norman H]

Looking at slowster's picture it's possible that the wedge itself is manufactured from steel. If not anyone who was handy with a file ought to be able to manufacture one that was.

[531colin]

Wow.
Whatever was wrong with a pinch bolt?
I thought all those things had died and been buried long, long ago.
(note the crack in the ali. wedge piece in the photo!)

[rjb]

It might be feasible to drill the wedge and retap it to 5/16" UNF. Its needs a tapping drill of 6.9mm
Table of thread dimensions here.
https://www.gwr-fasteners.co.uk/thread- ... ns-4-w.asp

[thirdcrank]

I have one of these on my 1980 Bob Jackson bought thanks to the largesse of the patron saint of police officers Lord Edmund-Davies. That was the first new bike I had ever owned and I splashed out on all what was then the top-spec kit including this stem. IIRC, the big gripe was that they often creaked, especially if not tightened up "just right" first time. Mine has never been undone since it went on the (Cinelli Mercx) bars. When it's been in for a respray I removed the stem and bars as a single unit. I suppose it shows that a posh name may mean little.

[Jdsk]

And the screw of interest is the one going into that receiver with the angled face?

Because if it is and the thread is damaged and it's a size that's hard to find then I'd consider getting a new receiver made with a more common thread.

As well as having the cracked aluminium piece repaired.

Jonathan

[foxyrider]

I bought a 1R in 1978 but whilst it looked the dogs, because the wedge tended to ovalize the bars, it was a complete b@*!h to make later adjustments. I went over to the rare as hens teeth (literally 6 month delivery from the factory in Japan) Shimano Dura Ace, which, whilst looking quite similar at first glance, used a different clamping arrangement that doesn't ovalize the bars.

[Mick F]

25miles today.
The bars were solidly in position.
Tried to move them, braked hard a few times on the hoods, and held the drops and pulled and pushed.
Solid as a rock.

Fitted in 1986, and only really released recently. Same Cinelli 64-40 bars.

Sleeping dogs.
Leave it alone, it works, and looks lovely.

[pq]

Of course if it gives no trouble you should leave it alone. I had a 1R long ago but soon sold it because it was heavier and worked less well than a 1A. But I missed the look of the 1R so bought an XA which looked like a 1R but had a 1A clamp which was almost completely hidden - best of both worlds. In fact it's still on the bike now although it's been gathering dust in the attic for a long time now.

But the best quill stem I've ever had was a Dura-Ace AX. Like the 1R it had a hidden clamping mechanism, but unlike the 1R it was properly executed so it worked and didn't flatten your bars. Cleverly it came with a very long allen key which meant you could have a short (and therefore very light) expander bolt which you reached with the supplied key. The same principal applied to the clamp mechanism.