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-   -   Seatpost, grease.... and bang goes the bolt. (https://www.bikeforums.net/showthread.php?t=1178964)

Last ride 76 07-21-19 12:54 PM

Seatpost, grease.... and bang goes the bolt.
 
I painted new highlights on my old milled Campy seatpost recently. Knowing how many folks had bad experiences with siezed posts, i decided to put some grease on it before re-inserting. Let me add, this is the original post from 1975. No previous history of seizing or anything else.

After. riding a little way, I decide my position on the bike feels "funny"... I haven't ridden it in 2 weeks but the is the bike all the others are set from. I've been having a fling with an '02 LeMond I was debating selling. I was having so much fun on it (even though I find the cockpit ugly), I kept riding it day after day. I decided the LeMond must be to "blame", there must be some small variation in the fit.


Thump, I hit a small pothole and It was pretty obvious what's wrong. My saddle was 3/8 inch lower that when I started out. By the time i got to my LBS, it was 3/4 inch lower. So I went to the tool station, loosened the bolt, pulled the post back up and tightened the bolt. but in testing it, I could turn it, not easily, but...So I tighten a little more, and bang, the sound of a bolt shearing. Happily just a brand x cro mo bolt, it's not a big loss.

I went inside, and held up the bolt to one of the guys... They had the TdF on a big screen, the final few k's at that point, so I watched it. When I turned around after the finish, the mechanic, who's been there for years, and helped me out before with C&V bits says, "Sorry, we don't have one." I said, "it's ok, one just to get me home will be fine." "Yeah that's what I've been looking for", he said. Apparently the tech has moved on.:twitchy:


Riding 3.5 mi home was awkward but not too bad. The funny ending...

There was a rather battered vintage bike listed on ebay, over in a few hours, last night. Brand unknown but a mix of worn Campy, and shimano 600 parts.


For $141, I get my $20 Campy replacement seatpost bolt, plus the rest of the bike, including bar end shifters, NR derailleurs, cranks, and record wheels - high flange rear, low front (tipo skewers). The seller? The same LBS (on consignment). I stopped by the shop on my ride this morning, and made arrangements to pick it up...right now.:)

cudak888 07-21-19 01:48 PM

Not fun! Surprised even an LBS wouldn't have a simple seatpost bolt (or be able to kludge one together). Sounds like you might have had more luck at the LHS (local hardware store)!

Don't put too much faith in the used Campagnolo seatpost binder bolt either. I've found they'll tighten twice before snapping entirely.

-Kurt

AdventureManCO 07-21-19 02:24 PM

While not vintage appropriate, would the bike shop have had a basic quick release style seatpost bolt that could have fit the hole and gotten you home?

merziac 07-21-19 02:27 PM

These bolts are crap in general, we know this.

I grease the threads on every one with anti seize, never broken one yet.

Greasing the SP can be tricky, I do it sparingly then wipe down the SP after it has greased the ST before carefully cinching down the bolt having lubed it too. ;)

The Golden Boy 07-21-19 04:26 PM

I always grease the seatpost...

As far as the quick release seatpost bolts... do you just put it in- and squeeze the ears together from the outside? Is that OK for regular bikes?

Last ride 76 07-21-19 04:28 PM

https://cimg7.ibsrv.net/gimg/bikefor...534b359f78.jpg

And done.

Originally Posted by merziac (Post 21037939)
These bolts are crap in general, we know this.



I grease the threads on every one with anti seize, never broken one yet.



Greasing the SP can be tricky, I do it sparingly then wipe down the SP after it has greased the ST before carefully cinching down the bolt having lubed it too. ;)





Greasing the bolt, now why didn't I think of that?:rolleyes: Yeah, I do know they are prone to breaking, mostly in removal, and often sieze... oh wait,:bang: :D


Now I get it, common sense, though it generally isn't.*




*common, that is. Hate when that phrase applies to me.:rolleyes:




Of course we could have made something work. bolts, nuts, washers - not in short supply. But it was Saturday, late morning in a busy shop on a major bike route. He looked where he thought he might find one sitting in an old parts bin, as a favor to me, since they don't have them for sale. Lowes is less than a mile away, also, if I had been far from home, I would have asked (the shop people know I'm local).

bertinjim 07-21-19 04:54 PM

Binder bolts
 

Originally Posted by cudak888 (Post 21037877)
Not fun! Surprised even an LBS wouldn't have a simple seatpost bolt (or be able to kludge one together). Sounds like you might have had more luck at the LHS (local hardware store)!

Don't put too much faith in the used Campagnolo seatpost binder bolt either. I've found they'll tighten twice before snapping entirely.

-Kurt

I was in a local high end shop a year ago and tried to pick up a cro-mo seatpost binder bolt. The tech looked and finally found one but commented that there was no demand and they would not re-stock.

JohnDThompson 07-21-19 05:18 PM


Originally Posted by cudak888 (Post 21037877)
Don't put too much faith in the used Campagnolo seatpost binder bolt either. I've found they'll tighten twice before snapping entirely.

Campagnolo seat post binder bolts are notorious for breaking. I've broken several over the years. I've had better experiences with Zeus, Sugino, and TA binder bolts; haven't broken one yet.

cudak888 07-21-19 05:38 PM


Originally Posted by bertinjim (Post 21038151)
I was in a local high end shop a year ago and tried to pick up a cro-mo seatpost binder bolt. The tech looked and finally found one but commented that there was no demand and they would not re-stock.

They're in the J&B catalog, problem is that one has to keep a supply of them, just in case. The Chinese ones I was picking up about 10 years ago (with slightly domed heads) are excellent; haven't had any of them give trouble re-tightening.


Originally Posted by JohnDThompson (Post 21038203)
Campagnolo seat post binder bolts are notorious for breaking. I've broken several over the years. I've had better experiences with Zeus, Sugino, and TA binder bolts; haven't broken one yet.

Whatever metal Campagnolo was using, it can't take the stress. It's brittle and always snaps at the thread edge.

Suginos are my go-to. They look just like Campag and you'll find them on gas-pipe junkers on occasion. Always worth it to clean the rust off of them and re-use.

-Kurt

RobbieTunes 07-21-19 08:06 PM

Yep, the Campy ones break. "I learnt that up the same way."
Part of earing your C&V stripes.

I use Sugino and make believe they're Italian. Ends in "o."

merziac 07-21-19 09:59 PM

It occurs to me that wire wheeling the threads on these should work wonders, smooth out the crappy machining, relieve the sharp, sticky stuff and likely tone down the stress risers. Combine that with the anti seize and we might be golden. ;)

greg3rd48 07-21-19 10:38 PM

The bike you picked up looks interesting and tiny. Do you have any idea what it is? Cool find and story!

Last ride 76 07-21-19 11:06 PM


Originally Posted by cudak888 (Post 21038220)
They're in the J&B catalog, problem is that one has to keep a supply of them, just in case. The Chinese ones I was picking up about 10 years ago (with slightly domed heads) are excellent; haven't had any of them give trouble re-tightening.




Whatever metal Campagnolo was using, it can't take the stress. It's brittle and always snaps at the thread edge.


Suginos are my go-to. They look just like Campag and you'll find them on gas-pipe junkers on occasion. Always worth it to clean the rust off of them and re-use.


-Kurt




+1 on the Suginos Ive only broken a couple of the Campys:notamused: the one I broke sounds like the chinese ones you mentioned. i have a few sitting around. But this is the bike had the most success with bit, and it deserves Campy, if not the best... I have looked unsuccessfuly for years, for a specific knurled seat post bolt, black anodised that I used back then. Funny it didnt sit flush in the socket, I don't even know if i would still like it. I think it was common on Teledynes too. though not black, maybe.


Has anyone ever used Plumber's Teflon Paste? It's very sticky for being having teflon in it, and has some sort of weird soft grit. I'll check it out tomorrow. But the grease down the tube, out. that post/tube combo was fine for over 40 years. Nope it wasn't broke... I sure fixed it, though.

cudak888 07-22-19 05:26 AM


Originally Posted by Last ride 76 (Post 21038658)
+1 on the Suginos Ive only broken a couple of the Campys:notamused: the one I broke sounds like the chinese ones you mentioned. i have a few sitting around. But this is the bike had the most success with bit, and it deserves Campy, if not the best... I have looked unsuccessfuly for years, for a specific knurled seat post bolt, black anodised that I used back then. Funny it didnt sit flush in the socket, I don't even know if i would still like it. I think it was common on Teledynes too. though not black, maybe.

Has anyone ever used Plumber's Teflon Paste? It's very sticky for being having teflon in it, and has some sort of weird soft grit. I'll check it out tomorrow. But the grease down the tube, out. that post/tube combo was fine for over 40 years. Nope it wasn't broke... I sure fixed it, though.

If it deserves the best, put Sugino on it. Anyone in the know should rightfully scoff at the Campy binders, which - if I'm not mistaken - are still made today and are just as inferior as they always were.

-Kurt

mpetry912 07-22-19 06:47 AM

those bolts are crap ! the bolt goes into shear when you tighten it (as the seat lug closes, there' a bending force put on it) and it's just a pot metal part.

here's what you might do - KEEP the "nut" side of the seat binder bolt. Find an M4 or M5 bolt, stainless steel, allen head in your junk box (you DO have a junk box right?) and use that as the "bolt". MUCH stronger. You may have to come up with a washer or spacer to make it work. On one bike I turned the bolt head down slightly so it would fit in the frame recess.

If the post fits properly you should not have to tighten the bolt that tight. 5 or 600 foot pounds should be sufficient :crash:

Seriously if 72 in/lb (6 ft/lb) is not sufficient then you might consider adding so punch marks or knurling the seat post below the insertion line to give some increased "bite". I have the excellent Stein knurling tool and do this on most bikes after I haver the saddle height finalized.

Mark Petry
Bainbridge Island, WA USA

https://cimg6.ibsrv.net/gimg/bikefor...222b5d2609.jpg

https://cimg0.ibsrv.net/gimg/bikefor...57811c7a93.jpg

Spaghetti Legs 07-22-19 07:25 AM

A true BF C+V er. Breaks part, buys an entire bike to get replacement!

I have yet to break a Campagnolo binder bolt, so will continue to read these threads to ensure that doesn’t happen.

easyupbug 07-22-19 07:27 AM

Carbon assembly paste works for me. You all probably know this but as a reminder the torque you use for a drybolt if applied to a lubed bolt can overload and break the bolt.

jeirvine 07-22-19 08:18 AM

I've read that the design flaw with the Campy bolts is that (above and beyond the crap metal) the unthreaded shaft part is too long, so it bottoms out on the female side before it's tight, and then the threaded bit snaps off when you continue to tighten it.

Chombi1 07-22-19 05:52 PM

Sugino seatpost binder bolts are supposed to be bulletproof, compared to the asploding Campys.
I've also been quite nervous about a seatpost "grub" bolt that is on my 1984 Peugeot PSV. It's a small bolt (smaller, I think, than the standard waterbottle mount bolts) that through a threaded waterbottle type boss and hole at the back of the seattube, jams against a groove on the back of the seatpost. To anchor it. It never gave out or slipped on me in the 35 years I have owned and rode the bike, but If might eventually do something bad on me during a ride and the wrong bump or pothole on the road. My proposed solution would be to find a 26.4 mm seatpost that has a quill wedge on it, so it will take most of the load off the grub bolt. I figure, the same solution should work for a constantly dlipping seatpost on a bike with a standard seatpost clamp. The seatpost clamp bolt will not have to he tightened so much then to maintain proper seatpost height.

Bad Lag 07-23-19 12:17 PM

Don't grease the bolt threads.

Use anti-sieze on the seatpost, not grease.


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