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Old 06-10-07, 09:04 PM   #1
mseanschmidt
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Campy Crank Problem?

I have a brand new Seven ID8 with full Campy Record. I'm using the 2007 Campagnolo Record Ultra Torque Compact Carbon Crankset 50/34. I have about 700 miles on the bike since I got it in the Spring. This week I started to notice a suptle "gyroscopic" type feel which has gotten a little worse with each ride. I spent my entire ride today trying to trouble shoot the cause. I cannot feel when I'm coasting at any speed so I think that eliminates the tires, wheels, etc. I've narowed it down to when I'm putting a significant torque on the cranks. Maybe 200+ watts or so I begin feeling a "gyroscopic" whine from the cranks as I turn the pedals. I do not get this when I am just spinning at low watts, only with some significant force on the pedals.

Any idea what could be causing this???? I have a 135 mile event this Wednesday and I'm concerned I could have a mechanical problem. Any input would be greatly appreciated. Thanks!
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Old 06-11-07, 12:02 AM   #2
Todd Richards
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unsure if it's related but I have some side-to-side play in my ut chorus crankset. it seems tha tthe ut crankset needs the bottom bracket spacing to be exactly 68mm. mine seemed to be .1mm or so on the narrow side, as when first installed the mech could press on the non drive side at the base of the crankarrm inward (along axis of bearings) and produce a little wiggle. we removed and placed a spacer between the bb shell and the outboard bearing, and the wiggle was reduced. adding another made the crank to tight, no wiggle but ddin't spin as good. a call to campy didn't really help, they seemed to think the mech didn't know what he was doing, which was very far from the truth. great guy with lots of expereince. anyway i've ridden it and although i can still produce the wiggle when i press against it as described above, i can't feel it when i ride. but it sounds as though this 'gyroscopic' feel you have might be caused by this small amount of play.
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Old 06-11-07, 12:05 AM   #3
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Originally Posted by Todd Richards
unsure if it's related but I have some side-to-side play in my ut chorus crankset. it seems tha tthe ut crankset needs the bottom bracket spacing to be exactly 68mm. mine seemed to be .1mm or so on the narrow side, as when first installed the mech could press on the non drive side at the base of the crankarrm inward (along axis of bearings) and produce a little wiggle. we removed and placed a spacer between the bb shell and the outboard bearing, and the wiggle was reduced. adding another made the crank to tight, no wiggle but ddin't spin as good. a call to campy didn't really help, they seemed to think the mech didn't know what he was doing, which was very far from the truth. great guy with lots of expereince. anyway i've ridden it and although i can still produce the wiggle when i press against it as described above, i can't feel it when i ride. but it sounds as though this 'gyroscopic' feel you have might be caused by this small amount of play.
. as i'm going to bed now, feel free to e-mail me with any comments direct to: sarahart@midcoast.com
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Old 06-11-07, 06:57 AM   #4
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The weird thing is it was rock solid for the first 400-500 miles. Then over the past 100 miles or so I started feeling this gyro-scopic feel when putting some significant torque on the crank. It is really a sound as much as a whinning type vibration from the crankset. Could this bottom bracket spacing increase over time?
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Old 06-11-07, 08:20 PM   #5
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Campy UT

There are 4 things you should both check:

1. Was your BB shell faced before the cups were installed? Is there still paint on them?This is important for all BB designs where the cups/bearings are mounted OUTSIDE the Bb shell,

2.The "Wavy washer" that came with the cups should soak up any variance in BB shell width. The tolerance is quite large here, so if the shell has been faced and the wavy washer installed on the non-drive side, you can get away with quite a bit.

3. Was the c-clip installed (and left there) on the drive-side cup? This is not just for installation. It is supposed to remain there. If it is removed, it can cause side-to-side play.

4. Was the 10mm bolt torqued to spec? This is EXTREMELY important. If it was, it will never come loose, if it wasn't it could easily loosen over a few hundred miles.

Hope this helps
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Old 06-11-07, 09:23 PM   #6
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Originally Posted by Bob Dopolina
There are 4 things you should both check:

1. Was your BB shell faced before the cups were installed? Is there still paint on them?This is important for all BB designs where the cups/bearings are mounted OUTSIDE the Bb shell,

2.The "Wavy washer" that came with the cups should soak up any variance in BB shell width. The tolerance is quite large here, so if the shell has been faced and the wavy washer installed on the non-drive side, you can get away with quite a bit.

3. Was the c-clip installed (and left there) on the drive-side cup? This is not just for installation. It is supposed to remain there. If it is removed, it can cause side-to-side play.

4. Was the 10mm bolt torqued to spec? This is EXTREMELY important. If it was, it will never come loose, if it wasn't it could easily loosen over a few hundred miles.

Hope this helps
+1, 2, 3, and 4!
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