Bicycle Mechanics - Some how I managed to lose

I lost this piece http://www.cheapbikeparts360.com/images/b/2254.jpg

Does anyone know how I would go about finding a replacement? I lost the black piece. It's for a shimano crank arm.

$5 bucks at your LBS.
They may have to order one.

Your local bike shop probably has one. What crank do you have?

Your local bike shop probably has one. What crank do you have?

Shimano Ultegra triple.

Shimano Ultegra triple.

Make sure you get the right cap. There are 2 different ones.

Is that the dust cap? Your bike will be perfectly safe to ride without it. If you ride through puddles / sand / snow, it's handy to have, but otherwise, as long as you clean your bike once in a while, you'll be fine.

Shimano Ultegra triple.

And make sure you get a Shimano tool to torque it onto the Ultegra triple. It requires somewhere around 8 inch-pounds. Getting the shop to do it will be cheaper than the tool. Two Methods? Choose #2.

bigvegan" it's not a 'dust-cap. It sets the preload on the cranks. THEN it's a dust cap.

And make sure you get a Shimano tool to torque it onto the Ultegra triple. It requires somewhere around 8 inch-pounds. Getting the shop to do it will be cheaper than the tool. Two Methods? Choose #2.

bigvegan" it's not a 'dust-cap. It sets the preload on the cranks. THEN it's a dust cap.

It also serves as a crank retention in case the actual crankarm bolts come completely loose.

Is that the dust cap? Your bike will be perfectly safe to ride without it. If you ride through puddles / sand / snow, it's handy to have, but otherwise, as long as you clean your bike once in a while, you'll be fine.


I believe this is wrong. This part is to your crank arms what your stem cap is to your stems adjustment. It's the "bolt" that sets the tension before you tighten up your pinch bolts. So theoretically once the pinch bolts are tight, this part isn't important....but in reality these Ultegra cranksets come loose under normal use, so this part is absolutely necessary in order to hand tighten the "bit" of tension to the BB bearings before tightening the NDS crank arm onto Crank spindle.

-Jeremy

this is one of those times when a good relationship with your bike shop can really pay off.

but in reality these Ultegra cranksets come loose under normal use

I haven't noticed that on our customers' HT-II bikes, whether road or mountain. Where'd you hear this? Maybe you're thinking of some other brand of crankset... when I was working at a Specialized dealership, we had quite a few Allez owners walk in with their left crankarm in their hand. What were those... FSA or Sugino, I believe.


Anyway, Caad 8, here's your item if you need to buy one online: http://aebike.com/product/ultegra-fc-6600-6603-xt-fc-m760-hone-m600-lx-m580-crank-arm-pinch-bolt-sku-cr2756-qc30.htm

My Ultegra triple hasn't come loose. And I ride the tar out of it. Very nice crankset. Very obnoxious making the bloody cap proprietary so most home-mechanics (most) have to buy their stupid tool.

I haven't noticed that on our customers' HT-II bikes, whether road or mountain. Where'd you hear this? Maybe you're thinking of some other brand of crankset... when I was working at a Specialized dealership, we had quite a few Allez owners walk in with their left crankarm in their hand. What were those... FSA or Sugino, I believe.


Anyway, Caad 8, here's your item if you need to buy one online: http://aebike.com/product/ultegra-fc-6600-6603-xt-fc-m760-hone-m600-lx-m580-crank-arm-pinch-bolt-sku-cr2756-qc30.htm


I own an Ultegra 10 road bike, and have for 3.5 years. I periodically have to removed the BB cups to grease and re-torque both the cups and the crank arms to get rid of little creaks and such. So my experience is first hand. Even if it's not technically the crank arm that's loose....but instead the BB Cups...You still have to remove the crank arms first...which means you need that cap to reinstall them at proper tension. I've been told by at least one LBS that this is typical. I've even heard a mechanic say that they have better luck with Ultegra 9 BB/cranksets staying torqued than with the 10 speed external cups. I can't comment on that claim though as I have no personal experience.

-Jeremy

My Ultegra triple hasn't come loose. And I ride the tar out of it. Very nice crankset. Very obnoxious making the bloody cap proprietary so most home-mechanics (most) have to buy their stupid tool.

If we want to give Shimano the benefit of the doubt, you could argue that by using that little plastic star tool, they made it just a bit harder for someone to walk off with your cranks and pedals. If you see a large Allen cap, you could show up with a full Allen wrench set and quickly walk off with someone's crankset having loosened 3 bolts. Older square taper cranks required a puller to remove, but the newer stuff is simply slid though the BB and only fastened on one side. Easily installed...easily stolen. Just a thought.

-Jeremy

but in reality these Ultegra cranksets come loose under normal use,\

No they don't. Pure fabrication.

Properly torqued parts don't come loose under normal use, that's why these torque spec EXISTS. We know that cap sets the preload on the crankset, that's not the issue here.


So my experience is first hand. Even if it's not technically the crank arm that's loose....but instead the BB Cups

If you're undertorquing the BB cups, and they come loose, how is that the crankset coming loose. Talk about misleading.

I've been told by at least one LBS that this is typical. I've even heard a mechanic say that they have better luck with Ultegra 9 BB/cranksets staying torqued than with the 10 speed external cups. I can't comment on that claim though as I have no personal experience.

-Jeremy

Yeah, well your LBS is a ******. We've been selling and working on external bottom bracket bikes since they were introduced. Whoever is telling you this obviously false information doesn't know what proper torque is, nor has the tools or the knowledge to ensure that parts are up to it.

I came back from a ride, unclipped, got off the bick, and then the arm fell off. I noticed the black piece was missing, and the two other bolts were very loose. Not sure how that happened because I check the bolts on the entire bike every so often.

Buy a torque wrench and learn what 12-15nm for those arms is supposed to be.

Very obnoxious making the bloody cap proprietary so most home-mechanics (most) have to buy their stupid tool.

Proprietary.... Its the cornerstone of Japanese business strategy. Ever hear of a company called "Sony"

The reason it is a proprietary hand tool is because the cap takes just the barest bit of torque to set the preload. If it were a regular Allen bolt you'd have every person who hadn't seen this crank style before coming back for new bearings after ruining their first set.

The reason it is a proprietary hand tool is because the cap takes just the barest bit of torque to set the preload. If it were a regular Allen bolt you'd have every person who hadn't seen this crank style before coming back for new bearings after ruining their first set.

Bravo! However, I still hate Sony and their media cards

Properly torqued parts don't come loose under normal use, that's why these torque spec EXISTS. .

It's true that my LBS never tightened my BB cups OR crank arm pinch bolts with a torque wrench. I'm doing this service for myself now, and have had consistently better luck with things staying in place, still not using the torque wrench. A torque wrench is my list tools to one day own. I apologize for passing on bad info here.

-Jeremy

The reason it is a proprietary hand tool is because the cap takes just the barest bit of torque to set the preload. If it were a regular Allen bolt you'd have every person who hadn't seen this crank style before coming back for new bearings after ruining their first set.

Exactly

I believe we've discussed this preload bolt design before on another thread.