Cranks spinning but not totally free

[jamin100]

I've just brought a new Ultegra crank and Ultegra Bottom Bracket for a titanium bike i'm building up.
I've installed both, but i'm not sure they "feel" right. with them both installed (but no pedals) they turn and I cant hear any funny noises but the dont seem to spin as freely as I would have thought.

For example, when i put a pedal on, I would have expected the side with the pedal to fall to the bottom straight away. Whilst it does get to the bottom, its not like my other cranks where it literally just falls to the bottom if that makes sense.

Also, if i spin the cranks, they stop pretty quick and dont spin for a while like the others.

Is this an issue? Any ideas what could be the cause?
Both the bottom bracket and crankset is new.

 

[faster]

How much preload did you put on with the plastic screw on the non drive side?

If you've done it up finger tight, that's far too tight imo.

The correct amount is as little as possible to remove play. Turn until you first feel resistance, then a tiny bit more. As little as you can.

Then tighten the pinch bolts evenly.

 

[C R]

How much preload did you put on with the plastic screw on the non drive side?

If you've done it up finger tight, that's far too tight imo.

The correct amount is as little as possible to remove play. Turn until you first feel resistance, then a tiny bit more. As little as you can.

Then tighten the pinch bolts evenly.

Yep, the spec according to Shimano is 1Nm on the plastic plug.

 

[davidphilips]

If it feels tight then theres some thing wrong Might just be a tight seal, First i would loosen the L/h crank arm bolts and preload, Does it now spin if so its the preload if not then remove the chainset and check the bearings are still free? Is the titanium frame threaded or press fit? try this and post findings, good luck.

 

[boydj]

It might just be the fact that the grease is fresh and new and cold. I have Speedplay pedals, which require regularly topping up the grease. I know this needs doing when the pedals spin freely. Recharge the grease and you'll only get a couple of turns if you try to spin the pedals. The grease doesn't impact on the feel when riding the bike.

 

[PpPete]

If it feels tight then theres some thing wrong Might just be a tight seal, First i would loosen the L/h crank arm bolts and preload, Does it now spin if so its the preload if not then remove the chainset and check the bearings are still free? Is the titanium frame threaded or press fit? try this and post findings, good luck.

If each bearing spins freely, but not when the crank is through (regardless of pre-load), then you may have an alignment issue in the BB shell of the frame. This can happen with both threaded and press-fit. Even some big name manufacturer's frames...

 

[ColinJ]

If each bearing spins freely, but not when the crank is through (regardless of pre-load), then you may have an alignment issue in the BB shell of the frame. This can happen with both threaded and press-fit. Even some big name manufacturer's frames...

I had that with my Basso. It was very odd in that the original BB that I had in it was fine, but the better one I tried replacing it with wouldn't turn properly when it was fully screwed in. That new BB worked perfectly well in another frame, and the original worked fine when I put it back in...

 

[davidphilips]

If each bearing spins freely, but not when the crank is through (regardless of pre-load), then you may have an alignment issue in the BB shell of the frame. This can happen with both threaded and press-fit. Even some big name manufacturer's frames...

Lol, Did not want to say that, just hoping its nothing as bad as that? Watched a few Hambini videos on utube and even some of the really expensive frames can have misalignment issues, he sorts them out in his own way.

 

[Ajax Bay]

BB shell misalignment (threaded) will surely not be the issue with an expensive titanium frame (better not be ).
Don't think that there's much grease in the bearings of a Shimano-bb-r60-ultegra-6800-bottom-bracket
So that is unlikely to be the issue.
So probably preload, as others have said.

 

[davidphilips]

Did you ever sort the issue jamin100?

 

[DRM]

BB shell misalignment (threaded) will surely not be the issue with an expensive titanium frame (better not be ).
Don't think that there's much grease in the bearings of a Shimano-bb-r60-ultegra-6800-bottom-bracket
So that is unlikely to be the issue.
So probably preload, as others have said.

I've watched a few of Hambini's videos and the main culprits seem to be carbon frames, but I do recall him slating some aluminium frames too, with misaligned bottom brackets, so I wouldn't put any faith in Ti being perfect, as the more expensive & desirable the frame, the crapper the alignment, he says that Look carbon frames are the gold standard production wise, however I would say if anyone watches him on you tube, turn the volume down first as he can be a bit sweary to say the least

 

[davidphilips]

Know what you mean about Hambini, hes got some very interesting videos but best to take them with a pinch of salt as the old saying goes, seen him run Cervelo bikes down on more than one video yet he owns Cervelo himself, know he could sort out any misalignment issue and a very cleaver guy, sort of cyclist you would never forget.

 

[CXRAndy]

I like Hambini, he is plain talking no nonsense approach to what should be simply engineering standards.

It really should not be difficult for a frame manufacturer to make truly round holes in alignment with correct dimensions- alot cannot

 

[DRM]

I like Hambini, he is plain talking no nonsense approach to what should be simply engineering standards.

It really should not be difficult for a frame manufacturer to make truly round holes in alignment with correct dimensions- alot cannot

Especially at the prices they charge for some of those frames, it's totally unacceptable.

 

[davidphilips]

Best way that bike frame manufactures could improve there engineering standards would be to employ Hambini as there quality control manager?