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CarlosTheJackal
- Posts: 63
- Joined: Tue Oct 30, 2018 4:56 pm
by CarlosTheJackal on Sun Jan 15, 2023 1:36 pm
steveadore wrote: ↑Sun Jan 15, 2023 9:17 am
CarlosTheJackal wrote: ↑Sat Jan 14, 2023 11:27 pm
It looks like Shimano knew there would be a problem with hard bearings on their axles and elected to put a plastic reducer in to mitigate this. I used to have a wheels mfg and praxis BB, both hard 24mm bearings directly onto the axle. They used to cut grooves in.
I have a Time Scylon with a Hambini BB. I had to do some filing on the inside as Time had left the stay overhangs too long. Once that was completed, I installed the Hambini BB and have never looked back. I would recommend his BB's they are well engineered and his technical support is second to none.
If Shimano has problems, then so would other crank manufacturers who use softer alloy axles (instead of Shimano's steel one), too, I guess
Btw, on my mountain bike I have a Hope 46 (PF30>24mm) BB adapter with 24mm ID bearings, but I have luckily got away without grooves cut in the Shimano axle so far. I would have preferred a BB with 25mm ID bearings and plastic spacers for that bike but none were available at the time I installed the Hope.
Did you have to do the filing just because of the stays inside the BB area? Or did you experience problems also because of the internal cable guide grommet being in the way of the BB sleeve?
Time left too much material in there so I filed the stays, it's quite obvious the overhangs are not structural, they are in free air. I undid the screw for the internal guide to make it loose and to allow for some movement. I put the BB in and then tightened it up.
I share your opinon on the metal contact. Any sort of misalignment is bound to cause some grooves in the axles. It will be worse on Aluminium types. There are numerous photos on this forum of grooves in 30mm axles.
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steveadore
- Posts: 386
- Joined: Wed Mar 04, 2020 10:01 am
by steveadore on Sun Jan 15, 2023 4:07 pm
CarlosTheJackal wrote: ↑Sun Jan 15, 2023 1:36 pm
steveadore wrote: ↑Sun Jan 15, 2023 9:17 am
CarlosTheJackal wrote: ↑Sat Jan 14, 2023 11:27 pm
It looks like Shimano knew there would be a problem with hard bearings on their axles and elected to put a plastic reducer in to mitigate this. I used to have a wheels mfg and praxis BB, both hard 24mm bearings directly onto the axle. They used to cut grooves in.
I have a Time Scylon with a Hambini BB. I had to do some filing on the inside as Time had left the stay overhangs too long. Once that was completed, I installed the Hambini BB and have never looked back. I would recommend his BB's they are well engineered and his technical support is second to none.
If Shimano has problems, then so would other crank manufacturers who use softer alloy axles (instead of Shimano's steel one), too, I guess
Btw, on my mountain bike I have a Hope 46 (PF30>24mm) BB adapter with 24mm ID bearings, but I have luckily got away without grooves cut in the Shimano axle so far. I would have preferred a BB with 25mm ID bearings and plastic spacers for that bike but none were available at the time I installed the Hope.
Did you have to do the filing just because of the stays inside the BB area? Or did you experience problems also because of the internal cable guide grommet being in the way of the BB sleeve?
Time left too much material in there so I filed the stays, it's quite obvious the overhangs are not structural, they are in free air. I undid the screw for the internal guide to make it loose and to allow for some movement. I put the BB in and then tightened it up.
I share your opinon on the metal contact. Any sort of misalignment is bound to cause some grooves in the axles. It will be worse on Aluminium types. There are numerous photos on this forum of grooves in 30mm axles.
Did you undo that fixing screw all the way out? Or just halfway or so? Does that not mess with the derailleur cable tension? And is it easy to tighten it up again (i.e. guaranteeing the internal guide will be back in the correct position and cable will be routed with the correct tension) after the installation of the BB sleeve?
Btw, have you seen this?
https://youtu.be/5r-tGk69qfI He doesn't do anything with the guide and the screw, but the overhanging end of the stays is definitely an issue
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Nezz0r
- Posts: 118
- Joined: Wed Apr 22, 2020 2:26 pm
by Nezz0r on Sun Jan 15, 2023 5:14 pm
If I groove my axle I'll replace it - the rotor axles are not very expensive and a separate component of the crank assy.
Edit: well. Eh, nevermind. My Chris king BB has plastic top hats.
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CarlosTheJackal
- Posts: 63
- Joined: Tue Oct 30, 2018 4:56 pm
by CarlosTheJackal on Sun Jan 15, 2023 6:01 pm
steveadore wrote: ↑Sun Jan 15, 2023 4:07 pm
Did you undo that fixing screw all the way out? Or just halfway or so? Does that not mess with the derailleur cable tension? And is it easy to tighten it up again (i.e. guaranteeing the internal guide will be back in the correct position and cable will be routed with the correct tension) after the installation of the BB sleeve?
Btw, have you seen this?
https://youtu.be/5r-tGk69qfI He doesn't do anything with the guide and the screw, but the overhanging end of the stays is definitely an issue
I only undid it a little to give a bit of movement. Installed the BB, then retensioned the cable. It was no drama at all.
It is definitely the overhanging stays that cause the problem. The internal cable guide was not an issue once it was loose.
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steveadore
- Posts: 386
- Joined: Wed Mar 04, 2020 10:01 am
by steveadore on Sun Jan 15, 2023 8:29 pm
CarlosTheJackal wrote: ↑Sun Jan 15, 2023 6:01 pm
steveadore wrote: ↑Sun Jan 15, 2023 4:07 pm
Did you undo that fixing screw all the way out? Or just halfway or so? Does that not mess with the derailleur cable tension? And is it easy to tighten it up again (i.e. guaranteeing the internal guide will be back in the correct position and cable will be routed with the correct tension) after the installation of the BB sleeve?
Btw, have you seen this?
https://youtu.be/5r-tGk69qfI He doesn't do anything with the guide and the screw, but the overhanging end of the stays is definitely an issue
I only undid it a little to give a bit of movement. Installed the BB, then retensioned the cable. It was no drama at all.
It is definitely the overhanging stays that cause the problem. The internal cable guide was not an issue once it was loose.
That's good to know. The screw may periodically need to be partially undone to let water out of the frame (in case it gets into the BB area through the exit hole of the FD cable)
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otnemem
- Posts: 399
- Joined: Fri Jun 28, 2019 7:55 am
by otnemem on Wed Jan 18, 2023 12:18 pm
Clearance for 28mm only and over 6.8Kg with extremely light and expensive kit in the lightest paint scheme. Very sad to say it's out of my shortlist.
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RDY
- Posts: 2414
- Joined: Thu Jul 30, 2020 10:31 pm
by RDY on Wed Jan 18, 2023 12:49 pm
otnemem wrote: ↑Wed Jan 18, 2023 12:18 pm
Clearance for 28mm only and over 6.8Kg with extremely light and expensive kit in the lightest paint scheme. Very sad to say it's out of my shortlist.
Weight is expected and reasonable. 28mm max on a 'new' road bike launched in 2023 is pretty facepalm though. Especially for a climbing bike, given that alpine roads can be pretty broken up in ANY country (except CH), due to the weather conditions, and any increase in width is going to help with cornering and braking. Would it really have been that difficult or costly to alter the molds to accommodate 32s?
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otnemem
- Posts: 399
- Joined: Fri Jun 28, 2019 7:55 am
by otnemem on Wed Jan 18, 2023 1:01 pm
IDK. Many of its competitors can be <6.5 with this sort of very expensive, very light kit (which means that a run of the mill version will easily be >7.5) while having clearance for 32mm tires... So yeah, I'm not going to accept the compromise.
Maybe the new Look will be more enticing. I have about 10 months until I pull the trigger so I can wait.
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RDY
- Posts: 2414
- Joined: Thu Jul 30, 2020 10:31 pm
by RDY on Wed Jan 18, 2023 1:07 pm
otnemem wrote: ↑Wed Jan 18, 2023 1:01 pm
IDK. Many of its competitors can be <6.5 with this sort of very expensive, very light kit (which means that a run of the mill version will easily be >7.5) while having clearance for 32mm tires... So yeah, I'm not going to accept the compromise.
Maybe the new Look will be more enticing. I have about 10 months until I pull the trigger so I can wait.
I don't think you're going to see superlight Time frames any time soon. Part of the USP is that they're really strong and overbuilt by the rest of the industry's standards. But 28s is just stupid IMO.
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otnemem
- Posts: 399
- Joined: Fri Jun 28, 2019 7:55 am
by otnemem on Wed Jan 18, 2023 1:25 pm
Again, looking at the competition, I except rugged/strong frames at this level to allow for 7.0Kg on an out of the box Dura-Ace model. Hell, even aero bikes are now getting in that range.
But as you said, the clearance is really the breaking point. I'm visiting Portugal and there's craters everywhere. Where I live isn't much better and the tarmac is generally rough. Having the option to sport 32mm or at least 30mm at the back is non-negotiable.
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RDY
- Posts: 2414
- Joined: Thu Jul 30, 2020 10:31 pm
by RDY on Wed Jan 18, 2023 1:44 pm
MrCurrieinahurry wrote: ↑Wed Jan 18, 2023 1:40 pm
Tbf sometimes claimed clearance Vs actual can be different might be worth checking with a shop that has one built up
Basso Diamante eps 12
By saying max 28mm (existing AdH) they're saying it hasn't changed. If it was better I'm sure it would be stated. If it was better, they probably wouldn't have added 0.5-1mm as that would make no sense. If it was better than 0.5-1mm more then it wouldn't be max 28 ...