Wahoo Silent Kickr/Kickr Core Faults

[alex_cycles]

OK Loctite 641 arrived yesterday so the bearings are now secured. I hope I don't have to change them every month. It came apart really easily with them greased. But I can't let the shaft get destroyed by fretting, so even if I do have to change them from time to time, so be it.

 

[alex_cycles]

I've done another 2000 miles on the Kickr v5 since my previous post. It's been performing very well. Just this week there seems to be a faint trace of clattering sound and a characteristic "clack" when the flywheel is stopping. I will need to investigate this soon. I suspect it's time to change the drive side bearing again. 2000 miles is better than 400, but you'd still expect it to last longer.

This guy reckons his SKF bearing usually last 4000-5000km (4000km is 2485 miles - so it's in the same ball-park). Still seems a bit low to me, but I suppose we are compensating for a 'wonky' flywheel. Although my flywheel doesn't 'feel' wonky, it must be a bit off balance.

Is it better to try and seek out some high quality bearings or do I just accept that I will probably have to do this every 6 months or so?

 

[CXRAndy]

Hi Alex

You could try angular contact bearings, or high precision (see tolerances) bearings. Some of these bearings can be super expensive, costly mistake of they don't last longer.

If you could find a local-ish company which could do dynamic flywheel balancing at a reasonable price, maybe worth a shout. At least get the flywheel checked for imbalance.

https://www.skf.com/uk/products/rol...ring-interfaces/tolerances-and-resultant-fits

 

[alex_cycles]

Hi Alex

You could try angular contact bearings, or high precision (see tolerances) bearings. Some of these bearings can be super expensive, costly mistake of they don't last longer.

If you could find a local-ish company which could do dynamic flywheel balancing at a reasonable price, maybe worth a shout. At least get the flywheel checked for imbalance.

https://www.skf.com/uk/products/rol...ring-interfaces/tolerances-and-resultant-fits

Super-expensive is not very interesting. The Zen bearings from Aire Velo cost £4 each. Those are what I have now and have lasted 2000 miles.

I've found some Enduro ones which might be better...
https://www.wychbearings.co.uk/6003-LLB-Enduro.html and
https://www.wychbearings.co.uk/6003-llb-max_enduro_bearing.html

I'll check out your SKF link. Ta

At the end of the day it's not a disaster to have to do this twice a year, but if I can get it down to once a year for an extra £10 that'd be worth it. I think the £400 I invested in the Kickr owes me a good couple of years of use and then I'll probably get something more current. Hopefully by then the indoor trainer market will have sorted itself out and they'll stop churning out crap.

Edit to add. I had one of the Zen bearings in stock in my spares so I stripped it all down and fitted that. Nothing of note to photograph this time. Glad to say that the shaft is still fine. The Loctite did its job well there and came apart OK with a bit of heatgun application and a regular twatting
Cleaned it all up, reassembled and now waiting 24 hours for the Loctite to go off. Then I can do a factory spindown and have it up and running for Tuesday's race.


Further edit to add I just found a place in Bristol that looks interesting if anyone ever needs a shaft making...
https://www.bomberbikeworks.co.uk/smart-trainer-servicing

 

[alex_cycles]

Latest development I've been getting some "clacking" sound which I think I've traced to the belt tensioner bearings...

https://photos.app.goo.gl/JxW6HLYaPt3ehEHKA
So I've just replaced them.

Already raced today so I will give it a spin tomorrow, then factory spin-down and see how it performs over the next few days.

I've got bearing pullers and presses galore now. It's lovely having the right tools for the job. One of the bearings I removed, if you shake it you can hear the balls rattling around. And since they're metal shielded ones you can't even inspect or regrease them. So replacement is the only option.

 

[alex_cycles]

After a warmup and a factory spindown I did a ride of Big Flat Eight with Assiomas as duals.

Hard to see how it could be any better than that, really. And no clattery clacking sounds.

Doing a race tomorrow, which will give a "proper" test.

Update to add... After 2 laps of Douce France in a race there is still no evidence of the "clack" sound so I'm pretty sure now that it was due to the tensioner bearing. What this means is that the last time I changed my flywheel bearing in October was probably unnecessary because it was due to that sound. I thought it was fixed at the time - probably because I'd done the belt up a bit less tightly when I did that bearing swap.
Live and learn. if I ever have to change these tensioner bearings again I will use rubber shielded ones so they can be greased. There seems to be no good reason to use ZZ metal shielded ones as the revs aren't going to be all that high.

8th Dec to add... a week down the line and it's good. Better than it's been so far to-date. Still no clacking.