NJS

I guess the PPI cash cow is coming to an end and the lawyers are looking for a new one. What better than a "stick it to the man" incentive, and all on a no-win-no-fee basis. Perfect!

That makes no sense. On the bike or on your back, you still have to accelerate and brake its mass. On the bike, the frame,wheels and tires take the strain; on your back, you do. And having mass flopping around high up on your back goes against every rule of mechanical efficiency, safety and ergonomic design. I guess you're arguing the man rather than the logic; and would claim that shouldering your wheelbarrow saves on tyres.

Fair enough, but presumably most of that cannot actively benefit you; the 'spare' battery pack could.

Why carry dead weight, when you could parallel the packs, spread the load across them and extend their lives?

I'd put a little silicon inside the nose of each gland from the inside, and wrap some self-amalgamating tape around the outside; and try it for a while. At worst it cost you £5 or £6. Don't forget to grease the seal before you close up the box.

No one was suggesting it was a substitute for potting compound. Used inside the gland, where the gland has removed the vast majority of flexing; or on the outside of the gland and over-wrapped whilst still wet with self-amalgamating tape or shrink wrap, it'll last months for anything other than full immersion. And its cheap and easily replaced. Potting's great if you never need to undo it.

Seal the gland with silicon sealant. If he needs to take it apart, it peels off.

They make 'good' fleet cars, are usually well maintained and then hit the market after 2 or 3 years at 1/2 to 1/3rd their original price.

Are bare cells from NL any good to you?

Several of those axle shear failures have been definitively identified as having originated at pits caused by corrosion in the open hollow steel shafts. Preventing that corrosion would prevent those failures. Waxoil coating the interior of those hollow shafts would have prevented the corrosion. And that was all I suggested. However, aluminium also corrodes. Place a crystal of road salt on a piece of aluminium and add a drop of water, wait a week and see what happens. A waxoil coating would also slow down, if not totally prevent, that also.

Most of those crank failures a shear failures. Shear failures start with stress risers. Rusting causes pitting. Waxoil is not "lubrication", but rather a rustproofing fluid used to prolong the life of steel. It works by excluding water and air from bare metal and by slowing the progress of existing surface rust using phosphoric acid rust inhibitors. No rusting, no pitting. No pitting, no stress risers.

He's a small sample of hollowtech II failures findable on the web. All separate, all verifiable. Many severe injuries. At least one death. A small percentage of those is use; and if those odds are acceptable to you, ignore this. If not, an ounce of prevention just might save you from becoming a statistic. http://s32.postimg.org/5rdqbbp39/unknown.jpg http://oi57.tinypic.com/2ms35hh.jpg http://www.killasgarage.bike/wp-content/uploads/2017/05/Broken-Crank-Spider.jpg http://farm9.staticflickr.com/8395/8610646958_dc1056cb74_c.jpg http://forums.roadbikereview.com/attachments/components-wrenching/315662d1471225324-ultegra-crank-left-arm-falling-off-crank.jpg http://3.bp.blogspot.com/-AbUxa6XGnW8/TcLOqfX_p8I/AAAAAAAAAVc/hqk4Tj1N3-0/s1600/good+shot1.jpg http://www.timetriallingforum.co.uk/uploads/monthly_05_2009/post-4715-1241647179.jpg

Uh huh!

£10/year for peace of mind an overreaction. Hm. If you say so.

I'm pretty sure that Alan Farrina would have said the same right up until the day his sheared. For the sake of a quick spray inside once a month -- say a £10 can a year -- I'd rather that effort than end up under bus if it let go in traffic. Maybe he was unlucky, but it doesn't seem to be an isolated incident.