Pictures wont post
Here is link with pictures https://www.cyclechat.net/threads/wahoo-silent-kickr-kickr-core-faults.2...
Hello there my Silent Kickr V4, and Silent Kickr Core users or pending users. I've decided to make public a few niggles which some users have been having with Wahoo's latest Silent Kickr. These issues have been made public else where, I'm not the first and probably wont be the last.
The two common mechanical problems are knocking and a drone sound whilst using the turbo.
The knocking usually occurs whilst varying pedalling power, either applying more or relaxing. This is caused by the bolt on the bottom pulley, not being tightened properly. It holds the pulley in place by way of a Woodruff key assembly, the Woodruff key is not an interference fit and has a little free play. If the bolt is loose or works loose then the pulley twists on the shaft causing the clunk.
See below the location of the bolt. The remedy is to undo the bolt apply a little more blue thread-lock paste and re-tighten properly(hand tight with Allen key, but not excessive).
Edit, I've heard that Wahoo are replacing the Woodruff key for one that is a tighter fit. I'll look into this and report back
This I tracked down after my belt was very squeaky after a turbo session and the drone noise appeared. I removed the belt to isolate the fault and found its in the main flywheel assembly. There is nothing you can do to remedy this fault if you've ridden the turbo at all from new- its a warranty return to the supplier or Wahoo.
I believe it's down to the belt tension being too tight. The belt can have only few few mm slack from new, but once slackened mine worked even upto 12mm of play (measured from cowling)
When you've ridden the turbo for a period the pulleys slightly expand and increase further the tension, this then damaged the bearings(flat spotting the balls and race)-once damaged that is it!
Remedy to both problems
I reckon there is a potential remedy to both problems, if you take immediate steps when your new Silent Kickr arrives.
Before you ride the kickr!!
Remove the side cowling, its held on with a variety of small screws and Allen bolts. Its very easy to remove to see the fully belt path and tensioner.
Remove the centre bolt and apply thread lock and tighten- this cures knocking sounds
slacken the belt tension off.
Loosen the the tensioner holding bolt on the plate and then with a 2.5mm Allen key wind anti-clockwise 5 full turns. Dont forget to retighten the lock bolt on the plate.
You could go more until you feel the belt slip on the bottom pulley- then apply just a little more tension to the point it doesn't slip. This will relieve the pressure on the flywheel bearings and remove the belt squeak.
Edit 12 October '18
This is my turbo now after belt tension has been reduced. The noise is still there but much reduced .