Changing to triple -Octalink or Hollowtech II ?

[PpPete]

Am planning to replace worn out BB and double chainset for a triple (9 speed)
Would quite happily have stayed square taper, but suitable road chainsets seem to be all either Octalink or Hollowtech II external bearings. Having read on previous posts that Octalink is not great, went to LBS to ask about cost of facing BB shell (as I understand that is necessary for external bearings)
They quote £20 - £25 just for the facing, which seems like a lot. I know the kit to do it is expensive and they have to recover their costs somehow, but that seems OTT to me. Anybody any experience of this with other LBS ? How much did you get charged ?
Or is there another way to make the change to triple at lower cost….?

 

[Chris James]

Having read on previous posts that Octalink is not great

Have you read all the various stuff about how poor the reliability of hollowtech bearings are?!!

(To be fair, they MAY have sorted them out now)

I have an Octalink bottom bracket and have had no problems so far ... fingers crossed.

 

[spandex]

Am planning to replace worn out BB and double chainset for a triple (9 speed)
Would quite happily have stayed square taper, but suitable road chainsets seem to be all either Octalink or Hollowtech II external bearings. Having read on previous posts that Octalink is not great, went to LBS to ask about cost of facing BB shell (as I understand that is necessary for external bearings)
They quote £20 - £25 just for the facing, which seems like a lot. I know the kit to do it is expensive and they have to recover their costs somehow, but that seems OTT to me. Anybody any experience of this with other LBS ? How much did you get charged ?
Or is there another way to make the change to triple at lower cost….?

1st yes it dose cost a lot as the LBS has to buy in the tools the cheapest I could get them in today is

£256 for the BB shell facer
£198 for the BB tap set

And that is for the cheap S**T. for better but not the best it is

£376 for the BB shell facer
£587 for the BB tap set

The thing is these tools do not get used that much unless the LBS makes frames or builds up frames to order. So they are just sitting there!

BTW I Would not take any of my bikes to a LBS if they where using the Cheapest of the cheap tools.

So as you asked is there a way you can get it done cheaper? Yes go with the Octalink as it is just like the BB you have in there at the moment.

 

[kyuss]

Have you read all the various stuff about how poor the reliability of hollowtech bearings are?!!

(To be fair, they MAY have sorted them out now)

I have an Octalink bottom bracket and have had no problems so far ... fingers crossed.

The poor reliability is simply down to not having perfectly square BB shells. Get the BB faced and there should be few problems. They are dirt cheap and dead easy to replace anyway, a Hollowtech 105 BB is £13, the same in octalink is £25, and you don't need to worry about getting the right axle length with Hollowtech either.

Octalink aren't exactly renowned for reliability. Plenty stories out there of stripped splines and cranks coming loose.

I'd pay the £20 and get the BB faced and go with Hollowtech II.

 

[spandex]

I know what you mean I had Octalink on my Marin and I had endless amount of creaking and I could get rid of 90% of it but the 10% was doing my heat in. I am so glad I sold it

 

[Steve Austin]

You got two choices
1: get it faced
2: don't get it faced and see what happens.

I always go with 2. If the BB works fine and lasts a while* then i have saved the money facing a BB. If it doesn't last very long and i need to get it faced then i have only wasted the cost of a BB which wouldn't have lasted very long anyway.

*at least 6 months is good ime

 

[Smokin Joe]

You got two choices
1: get it faced
2: don't get it faced and see what happens.

I always go with 2. If the BB works fine and lasts a while* then i have saved the money facing a BB. If it doesn't last very long and i need to get it faced then i have only wasted the cost of a BB which wouldn't have lasted very long anyway.

*at least 6 months is good ime

Same here.

I've never seen the value of facing the shell anyway. The threaded fit between cup and bore is long and snug enough to stop the cup from ending up askew just because the faces might not be parallel. All that happens is the shoulder on the cup makes uneven contact with the shell.

 

[Mr Pig]

My mate fitted Hollowtech cranks to his MTB himself, I had no idea you were supposed to get the BB faced. He just banged it in! That's over six months he's been running it and so far it's good.

I've got the Octalink on my new MTB, guess I'd best keep an eye on it.

 

[dodgy]

I've got Hollowtech II on 3 bikes (2 x road and 1 MTB), no noises, clicks or annoyances. The MTB is still on the original bearings (3 years old).

 

[Dave5N]

Same here.

I've never seen the value of facing the shell anyway. The threaded fit between cup and bore is long and snug enough to stop the cup from ending up askew just because the faces might not be parallel. All that happens is the shoulder on the cup makes uneven contact with the shell.

Yep. I don't bother and i don't have problems. Headtube always seems more critical.

I don't see how you can get it askew without crossthreading it.

Seems one of these modern things that have come in in the last few years. Gives struggling bike shops a chance to make a few extra bob I suppose.

 

[Mr Pig]

I don't see how you can get it askew without crossthreading it.

I've never used/fitted one of these Hollowtech jobs but I have a lot of experience with bearings of various types and mounting configurations.

I would expect that if the bearing cups screw into the ends on the BB, and the faces were not flat, the cup would be pulled onto the face, and therefore be squint, if enough force was applied.

 

[Smokin Joe]

I would expect that if the bearing cups screw into the ends on the BB, and the faces were not flat, the cup would be pulled onto the face, and therefore be squint, if enough force was applied.

I removed a square taper bb from my frame recently. The paint had been completley removed about half way round the face of the shell, the rest hadn't. So obviously the shell wasn't squared, but the bb cup had not been pulled askew but had sat square in the frame otherwise paint removal would have been round the complete circumference.

 

[Mr Pig]

That's a square taper, different. The threaded section and end flange are part of the bearing housing itself, which on the square taper is the full width of the bottom bracket. The end of the housing can't tilt off true to conform to the shape of the frame because of the length and strength of the housing. The whole housing would have to either bend in the middle or move laterally at the far end. I'm sure you could twist one but it would take a lot of force, probably more than the drive surface material would take.

On Hollowtech the two bearing housings are narrow and not connected. They could twist off true far more easily. In fact I don't think it would be hard to do at all.

 

[Dave5N]

That's a square taper, different. The threaded section and end flange are part of the bearing housing itself, which on the square taper is the full width of the bottom bracket. The end of the housing can't tilt off true to conform to the shape of the frame because of the length and strength of the housing. The whole housing would have to either bend in the middle or move laterally at the far end. I'm sure you could twist one but it would take a lot of force, probably more than the drive surface material would take.

On Hollowtech the two bearing housings are narrow and not connected. They could twist off true far more easily. In fact I don't think it would be hard to do at all.

Well now, I got one on a 'cross bike with an unfaced shell (name and shame time it came from Chainreaction) and you tend to get a lot of force and stamping in 'cross, but the BB is true enough.

 

[Dave5N]

and not connected. They could twist off true far more easily. In fact I don't think it would be hard to do at all.

If they are screwed in right I don't see how they will move beyond the tolerance in the thread.