GXP with Wheels BB30 adapters excess drag

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eric
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Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
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by eric

I have a GXP crank in my BB30 FM066 using the Wheels adapters which are basically spacers between the crank and the BB30 bearings. With the Red crank that worked well. But when I installed a Quarq Cinco and torque it dow there's a lot of drag. It feels like there's preload on the bearings. I have none of the Wheels spacers installed. If I loosen the crank some it rotates with less drag.

Has this happened to anyone? Do you think it's something else? When I get to it next I'll measure the spindle length on the two cranks and see if the Quarq is slightly shorter.

I have a lathe, should I shorten a spacer? I think if I do that I should shorten the NDS one to maintain the correct chain ring offset.

by Weenie


Janders
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Joined: Fri Jun 04, 2010 8:56 am

by Janders

I had the same problem. PF30 frame, GXP Red Quarq (newer model).

If I torqued it "appropriately" there was a great deal of drag (30-50w!). If I kept it loose enough to spin right... it was jiggly and loosened further on its own.

Instead of futzing with the wheels adapter, I got a different brand when screwed into a normal PF30 BB making it into a gxp... this one worked perfectly.


jrennie
Posts: 496
Joined: Mon Oct 23, 2006 2:56 pm
Location: Reno, NV

by jrennie

Add a wave washer to the drive side arm and it will be smooth.

thisisatest
Shop Owner
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by thisisatest

... I doubt it. He's already running zero spacers. It's unlikely that the right crankarm is touching the right adapter. So the wavy washer will only add issues.

Just to make sure, this is the same frame you had the Red crank on, correct? same bb, same adapter, same exact setup... Most all the Quarq cranks I've dealt with had 30mm spindles. if I were to guess, I'd say the wheelsmfg adapter is hitting part of the Quarq spider before everything tightens down. Try, with the crank off the bike, sliding the adapter on the spindle and see how far it goes on before hitting something.

jrennie
Posts: 496
Joined: Mon Oct 23, 2006 2:56 pm
Location: Reno, NV

by jrennie

I think the issue is the length of the quarq spindle. I had the same issue(spec osbb w/wmf adapters) tons of drag with no spacers and free with 1 wave washer on drive side.

eric
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Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
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by eric

thisisatest wrote:.
Just to make sure, this is the same frame you had the Red crank on, correct? same bb, same adapter, same exact setup...

Yep.
thisisatest wrote:Most all the Quarq cranks I've dealt with had 30mm spindles. if I were to guess, I'd say the wheelsmfg adapter is hitting part of the Quarq spider before everything tightens down. Try, with the crank off the bike, sliding the adapter on the spindle and see how far it goes on before hitting something.


Worth checking, as is adding a washer on the DS (which could address the same problem).

Unfortunately the Praxis BB30 adapter BBs are Shimano only. KCNC makes a GXP one but I've read a couple complaints about them creaking.. and the Wheels adapters I already have are lighter and worked just fine on the old Red crank. If I can just figure out why they're not working on the Quarq.

by Weenie


eric
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Joined: Tue Nov 11, 2003 9:47 pm
Location: Santa Cruz, California, USA
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by eric

I figured it out. The Quark DS crank has some tiny tabs where the BB seats against the crank which stick out about .18mm from the face. They are on the outer edge of where the bearing is supposed to seat. The Wheels BB30 adaptor bottoms out on those bolts and tabs while the regular GXP bearing is smaller diameter and doesn't touch them. Measuring from the end of the spindle to the tabs I got about .15mm shorter than the other Red crank which just fit in this frame with no spacers. The frame's BB shell is 68.18mm which is close to the wider edge of the BB30 68.0 +- .2 mm spec.

The solution was to use a lathe to remove .2mm from the outer 4mm of the face of the Wheels adaptor to provide clearance for the tabs. If the frame had been at the middle or smaller size of the BB30 spec then I would not have noticed this at all.

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