FINALLY got my Lightning cranks to stop creaking!

Discuss light weight issues concerning road bikes & parts.
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Chris_W
Posts: 71
Joined: Mon Oct 13, 2008 11:20 am
Location: Lausanne, Switzerland

by Chris_W

I've had a set of Lightning cranks for a couple of years, but have used them on and off in my Specialized Tarmac SL4 frame with a BB30 bottom bracket because they tend to creak. The creaking comes and goes for several kms at a time, and I've tried several things to fix it. It's been exactly the same in two different SL4's (the first replaced after a car cracked the rear end) and both frames were noise-free when running a Shimano crank in BB30 bearings using some axle-thickening adapters (24mm to 30mm) from Specialized. So I was pretty sure that the problem was not the frames.

To use a Lightning crank in a BB30 frame, you need to use their adapters that press-in to the BB30 shell to make it wider, then regular BB30 bearings press-in to the adapters:

Image

I was pretty certain that the problem was the Lightning adapter cups moving inside the frame, especially because I could pull one side out with my fingers, and the other side wasn't much tighter. I emailed Lightning about this but they didn't offer any solutions. Based on things I read on this and other forums, I decided to try installing the adapter cups with Loctite 603 / 609 which should solve this sort of press fit issue, but the cranks still creaked and when I gave up and removed them for the last time, they still weren't in there very tight.

Because of all this, I haven't used the Lightning cranks for several months. Then when looking at other cranks I realized that the Lightning cranks are essentially BB386 cranks (30 mm axle, but designed for an 86mm wide BB), even though they are not described as such. I therefore decided to try some BB386 to BB30 adapters that FSA sells:

Image

These work with a different principle from Lightning's adapters in that you put the BB30 bearings into the frame as normal, and these FSA spacers effectively shorten the axle to be like that on a BB30 crank. I wasn't certain that they'd be the correct length, but they installed on the Lightning cranks perfectly, and with the bearing-preload adjuster turned in just half a turn they span really smoothly with no hint of play. I've now done a couple of long test rides and have had blissful silence. So I'm happy to be able to use my Lightning cranks once again.

I'm not overly keen having something with an FSA logo on my bike, but it's a small price to pay to get rid of all of that creaking.

dmoneysworks
Posts: 313
Joined: Tue Aug 07, 2012 6:35 am
Location: Parakai, New Zealand

by dmoneysworks

Top effort Chris!

by Weenie


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BeeBee30
Posts: 1473
Joined: Sun Dec 21, 2003 8:32 pm
Location: WALES,UK
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by BeeBee30

Only problems I can invisage is that the Lightning cranks aren't designed to use bearing that sit more inboard than where the original adapters place them, could the axle be strengthened in the area the original bearings would sit? But its a great solution and regarding the FSA logo's, acetone?
Ti or dye!

The Weenie formally known as CAADHEAD

Ceebers1
Posts: 35
Joined: Sun Apr 25, 2010 6:29 am

by Ceebers1

Hey Chris,
Does your Tarmac have the Delrin pressfit cups epoxied into the frame?

A few years ago, they just pushed the cups in, then they sent 3M 420 2 part with them, now the majority of them come epoxied in the frame.

Chris_W
Posts: 71
Joined: Mon Oct 13, 2008 11:20 am
Location: Lausanne, Switzerland

by Chris_W

My frame is the second-tier Pro model, not the S-Works (the 100 grams weight saving is not worth an extra $1000 for me). The frame therefore has a standard metal sleeve for the BB instead of the delrin cups pressed into the carbon - the delrin cups only seem to introduce one more potential loose fit, and so I'm happy to not have that system.

Taking another look at the installation, the preload adjuster ring is actually turned in about 3 full turns (not half a turn as I said in my original post), so is pretty much in the middle of it's range.

I'm not too worried about the cranks not being designed to have the bearings a little inboard - I was ready to give up on this crank anyway so if this causes any more problems over time then I'll just ditch it and won't be any worse off than if I hadn't tried this solution. I'll update this thread if I do have any further issues, but on a 80km ride yesterday with lots of climbing the cranks were again silent. :)

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djconnel
Posts: 7926
Joined: Wed Sep 26, 2007 1:57 pm
Location: San Francisco, CA
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by djconnel

I had to lube my spider interface. That worked. No BB30 adopter.

by Weenie


otoman
Posts: 315
Joined: Wed Sep 17, 2008 6:25 pm
Location: Nashville!

by otoman

Very elegant solution. :beerchug: Nicely done.
Age and treachery shall overcome youth and skill
Courir c’est mourir un peu

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