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No Crybabies
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Riding my Mondonico Pista (fixed gear) this morning, I noticed a click from the crank area. It was getting worse and worse. Finally stopped and figured out that the left crank arm was touching the chain stay. How the heck was this happening? I was out in the country at 5:30 a.m., so best I could do was take my mini tool and try to tighten the crank bolt a little, figuring that it was allowing the crank to move around. Didn't help. Kept riding, and it got worse. As the sun got bright, I finally looked down and realized that the right side of the bottom bracket had backed out about 1/8". Most of my bikes are English thread, but the Mondonico is Italian, with regular threads on the right side. Sure enough, the bottom bracket had worked loose, allowing the axle to move to the right. This must be the "precession" thing that Sheldon Brown wrote about! Pedaling should tighten a regular thread on the right side, not loosen it. Well, there you have it. ( http://www.sheldonbrown.com/gloss_p.html#precession )

So, to avoid this, do you all just periodically tighten Italian bottom brackets, or do you use Locktite? I usually grease and use teflon tape to avoid creaking, but I think I'd pick creaking vs. coming loose. Suggestions?
 

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Loctite. And lots of torque. Some purist mechanics think loctite is cheating, but it works for me.

Precession is cool. Some people have the hardest time understanding it, but I tell them to try to remember the Spirograph.
 

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Fixed said:
So, to avoid this, do you all just periodically tighten Italian bottom brackets, or do you use Locktite? I usually grease and use teflon tape to avoid creaking, but I think I'd pick creaking vs. coming loose. Suggestions?
Right/right bottom brackets have been used for nearly forever in both Italy, France, and other non-English countries. We're talking of millions upon millions of bikes, dating from long before locktite existed.

If they were a serious issue, they would have changed, and the fact that they were used for so many years is evidence that they're OK. The caveat is that they have to be tightened properly when installed.

BTW- don't just tighten the right cup, loosen the left, tighten the right to just about as tight as you possibly can with a 12" wrench - I've never heard of one stripping - then adjust the BB from the left and tighten that one. Since you're doing the work anyway, this would be a good time to fieldstrip clean and grease the bearings.
 

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Tighten up

Fixed said:
Riding my Mondonico Pista (fixed gear) this morning, I noticed a click from the crank area. It was getting worse and worse. Finally stopped and figured out that the left crank arm was touching the chain stay. How the heck was this happening? I was out in the country at 5:30 a.m., so best I could do was take my mini tool and try to tighten the crank bolt a little, figuring that it was allowing the crank to move around. Didn't help. Kept riding, and it got worse. As the sun got bright, I finally looked down and realized that the right side of the bottom bracket had backed out about 1/8". Most of my bikes are English thread, but the Mondonico is Italian, with regular threads on the right side. Sure enough, the bottom bracket had worked loose, allowing the axle to move to the right. This must be the "precession" thing that Sheldon Brown wrote about! Pedaling should tighten a regular thread on the right side, not loosen it. Well, there you have it.

So, to avoid this, do you all just periodically tighten Italian bottom brackets, or do you use Locktite? I usually grease and use teflon tape to avoid creaking, but I think I'd pick creaking vs. coming loose. Suggestions?
As noted by FBinNY, people used right hand threaded fixed cups for decades before thread lockers were common in bicycles. You just need to really tighten the right hand cup.
 

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FBinNY said:
Right/right bottom brackets have been used for nearly forever in both Italy, France, and other non-English countries. We're talking of millions upon millions of bikes, dating from long before locktite existed.

If they were a serious issue, they would have changed, and the fact that they were used for so many years is evidence that they're OK. The caveat is that they have to be tightened properly when installed.

BTW- don't just tighten the right cup, loosen the left, tighten the right to just about as tight as you possibly can with a 12" wrench - I've never heard of one stripping - then adjust the BB from the left and tighten that one. Since you're doing the work anyway, this would be a good time to fieldstrip clean and grease the bearings.
AMEN! I've got a couple bikes with Italian BBs, and have never had a problem with the fixed cup loosening...nor do thousands of others. Not to say it can't happen, but the trick is to get the cup tight the first time like FBinNY states above.
 

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My DeRosa has an Italian BB and I had the same problem. I put some blue Locktite then tightened it using lots of force. It was not a problem getting it apart to do maintenance, and I reassembled it using the same technique.
 

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Making memories
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Mmmmm, Mondonico Pista. I've had the same problem with a couple of Italian threaded bikes and lots of torque solved it. Too scared to try locktite....anywhere.
 

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I've had quite a few bikes with Italian BBs -- Bianchis, Gios, Merckx, De Bernardi. Only once did the BB back out on one of my bikes, my Gios that I bought new from Excel Sports back around 2000. Like your situation, mine started backing out during a fairly long ride. I was able to make it home, but the crank arm had a very noticeable scratch/groove worn into it. My LBS fixed it by putting some Loctite on the threads. To their credit, Excel sent me a new crank arm and paid for the shop labor. I've still got 3 bikes with Italian BBs, but I've never had another one do that, so I assume it was an installation error.
 

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+1 Loctite. My Merckx had the same issue and the loctite had to be re-applied every season. And yes, that was torqued to spec.
 

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I have several bikes with Italian threaded BB. When I install them, I apply grease to the BB shell and the threads of the BB cups then use a beam torque wrench to get it to proper specs. Mine don't come out until I remove them.

I learned this the hard way about 4 years ago when I built up a Colnago Tecnos, my first Italian threaded BB frame, and had the same experience as the OP about 30 miles into my maiden ride on the bike. After a quick inquiry here on RBR about proper install procedure for Italian BBs, I bought a beam torque wrench and reinstalled. If you are used to using a 12" crescent wrench to install Eng. BB cups and think you have them tight, you will be very surprised just how much extra force you have to apply to get the Italian cups up to proper specs.
 

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No Crybabies
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Discussion Starter · #11 ·
ok

Removed, cleaned, and reinstalled with Blue Locktite and tons of torque, using a 24" socket handle and "almost lifting myself off the ground" force.

Fixed gear riding, with all the standing in the mountains, could exacerbate the problem, I suppose. Going up 18% grades at 15 rpms puts a lot of unusual forces on the bottom bracket, I'd imagine.

cdhbrad said:
I have several bikes with Italian threaded BB. When I install them, I apply grease to the BB shell and the threads of the BB cups then use a beam torque wrench to get it to proper specs. Mine don't come out until I remove them.

I learned this the hard way about 4 years ago when I built up a Colnago Tecnos, my first Italian threaded BB frame, and had the same experience as the OP about 30 miles into my maiden ride on the bike. After a quick inquiry here on RBR about proper install procedure for Italian BBs, I bought a beam torque wrench and reinstalled. If you are used to using a 12" crescent wrench to install Eng. BB cups and think you have them tight, you will be very surprised just how much extra force you have to apply to get the Italian cups up to proper specs.
 

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"almost lifting myself off the ground" force......without a torque wrench to measure, that's probably about right as that seems to be the force I have to put on my torque wrench to get it to specs. I usually have to get someone to stand on the rear leg of my Park work stand to keep it from tipping over when I do one of these. Best of luck with the new install
 

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Discussion Starter · #13 ·
yup

cdhbrad said:
"almost lifting myself off the ground" force......without a torque wrench to measure, that's probably about right as that seems to be the force I have to put on my torque wrench to get it to specs. I usually have to get someone to stand on the rear leg of my Park work stand to keep it from tipping over when I do one of these. Best of luck with the new install
You do this on a work stand? For me, anything involving those kinds of forces, meaning pretty much all bottom bracket and pedal work, I put the bike on the floor. I'd be afraid I'd put a big dent in the bike frame, even a steel one.
 

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Yes, on a stand. I have an old seatpost I install so I don't worry about the carbon posts I use possibly getting cracked. With the BB above the ground, I can position the wrench so that its always below the downtube when I start to apply the downward force so it can't hit any part of the frame. Have to be careful to keep the wrench engaged with the BB cup, that's why I get someone to stand on the workstand leg so I don't have worry about it tipping. .
 

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Fixed said:
You do this on a work stand? For me, anything involving those kinds of forces, meaning pretty much all bottom bracket and pedal work, I put the bike on the floor. I'd be afraid I'd put a big dent in the bike frame, even a steel one.
I agree .... I'd be very nervous about applying big force onto a BB while the bike is in a stand. I always do the final tightening with the wheels on the ground.
 

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OK without loctite

The first Italian BB bike I built up (with Campy), the BB came loose. I did not use a torque wrench but I thought I tightened it pretty well. When I re-installed it the second time I used a torque wrench. I could not believe how much effort it took to get to the spec torque of 70nm. It has not come loose since. No Loctite required
 

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My '85 Bottecchia has the same problem. The old school LBS in my neighborhood even warped a Phil Wood BB tool trying to proporly torque an Italian BB cup. We finally ditched the NOS Campy BB and broke out the Loctite red late one night to seat the Wood BB. No troubles since.
 

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with IT threaded bottom brackets I always just wrap some white teflon tape around the drive side BB cup before installing.

Never had one loosen, and easy to remove.
 

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You do this on a work stand? For me, anything involving those kinds of forces, meaning pretty much all bottom bracket and pedal work, I put the bike on the floor. I'd be afraid I'd put a big dent in the bike frame, even a steel one.
I agree .... I'd be very nervous about applying big force onto a BB while the bike is in a stand. I always do the final tightening with the wheels on the ground.
I'm another who tightens my BB's with the tires on the ground.
 
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