Hollowtech II widget

[theclaud]

I have an annoying click on every rotation which I think is crank-related (the non drive side of a Hollowtech II). It is getting louder. My friend Dr Evil seems convinced that it's about the torque on the pair of bolts that secures the crank to the spindle - however I've just noticed that the little plasticky widget plate thing that sits in the gap where the bolts thread through from either side is simply not there. I realize that I have never troubled myself overmuch about what exactly it does - I assumed it was just a shim or a failsafe - but I've had Hollowtech IIs on a number of bikes and I'm sure they have always had one. Presumably if it's not there then it is easier to overtighten the bolts, which may be where I have gone wrong. I don't know how it went missing or if it was simply never there and I didn't notice. Anyway, what exactly is it for and is its absence likely to be behind the click? Is my crank about to fall off? What is this widget called and can one get a spare widget?

Thanks!

 

[dan_bo]

This?

 

[ianrauk]

It's to tension the crank against the bearings. So yes, if it's not there then it could cause a click.

They need to be tensioned just right too. I learnt this from Hope's website.
Basically, hand tighten tight with the tool, ('Nip it uurp' he says in his norvern brogue) , then back it off a tiny bit.

 

[MacB]

It is called a preload cap and the tool to tension it is called a top hat tool.

It is but I thought TC was on about the little plastic hook/wafer that sits between the open aspect of the crank where the bolts thread through.

If it is then sorry, I've always wondered what it did as well.

 

[ianrauk]

It is but I thought TC was on about the little plastic hook/wafer that sits between the open aspect of the crank where the bolts thread through.

If it is then sorry, I've always wondered what it did as well.

Doh... good thing one of us is paying attention.

@theclaud I have some spare if you need.

 

[Crackle]

It is but I thought TC was on about the little plastic hook/wafer that sits between the open aspect of the crank where the bolts thread through.

If it is then sorry, I've always wondered what it did as well.

If she is, I can confirm I had no idea what it is meant to do and simply left the damn thing off.

 

[ianrauk]

The widget help stops the crank working loose and falling off.

 

[theclaud]

It is but I thought TC was on about the little plastic hook/wafer that sits between the open aspect of the crank where the bolts thread through.

If it is then sorry, I've always wondered what it did as well.

Yes - that's the thingummy. I once overtightened the preload cap and won't make that mistake again, so now I have found a different mistake to make instead.

 

[theclaud]

It is called a preload cap and the tool to tension it is called a top hat tool.

As an aside, I don't think it is. I have the Shimano tool for the cap and I also have a top hat tool, which is definitely something different. It looks a lot more like a top hat that the cap tool, funnily enough, is made of steel and has no teeth or splines. I assumed it does something with some other kid of crank...

 

[theclaud]

Doh... good thing one of us is paying attention.

@theclaud I have some spare if you need.

I will take you up on that, Ian - thanks!

 

[Crackle]

You don't need a special tool, a plastic tyre lever fits perfectly.

Your click might be an end of life one. Hollowtech don't have a wonderful life expectation.

 

[dan_bo]

As an aside, I don't think it is. I have the Shimano tool for the cap and I also have a top hat tool, which is definitely something different. It looks a lot more like a top hat that the cap tool, funnily enough, is made of steel and has no teeth or splines. I assumed it does something with some other kid of crank...

That's a widget for extracting octalink cranks.

 

[theclaud]

That's a widget for extracting octalink cranks.

Interesting! I have one Octalink crankset and it doesn't use it. It is self-extracting! Which is all very clever and admirably simple, but makes you feel like a numpty when you finally realize it after trying a thousand more violent ways to get the things off. DAHIKT.

 

[MacB]

Oh bollocks, so she is.

I wonder if I have ever posted anything on these forums about reading WITH comprehension?

 

[dan_bo]

That's a widget for extracting octalink cranks.

That's a widget for extracting none-self-extracting octalink cranks.