I agree that WD40 is not a lubricant. It does un-seize rusted parts, but those are the type of parts which should have had grease on them in the first place. WD40 will tend to deteriorate plastics, causing them to crack etc. So i’d keep it away from my bearings (because of the seals).
I’ve ridden my KH 24 up in the mountains on an overnight camping trip, which happended to rain the whole time and was terribly muddy. But when I got home I just popped the cranks off, carefully levered the cover off the bearings, cleaned them with $2 aerosol degreaser and rinsed with water, and repacked with a mountainbike bearing grease. (car axle grease is fine too) They go back together as original and last a lot longer than if they weren’t serviced.
Bike phycho
Those bearings would have lasted longer if you left them alone. The lip of the seal fits finely around the race. The inside is packed with grease from the factory. This will repel water, keeping it out of the bearing, even if submerged.
To check your uni bearings, remove the wheelset from the frame. Spin the outer part (race) with your finger. It should have some drag, because it is filled with grease. But it should not have sticky spots. On a motorcycle, any stick, no matter how slight, is cause to replace the bearing. On a uni, this is your call. You are unlikely to need to have it run another 10,000 miles before you can check it again, as is the motorcycle wheel bearing check interval. Failure will not be sudden and dramatic, instead, gradual, and noisy on a uni. This is why these strange rumors about how to service uni bearings can take hold. These bearings are very tough, and you can do all manor of bad things to them. and they will hang in there on a uni. On a motorcycle, no one ever takes a chance with a bearing. No one ever talks of messing with the seals. These bearings are the same on both motorcycles and uni’s. But on a motorcycle, the idea that you would do a 200$ tire change and 50 $ labour, and then pry the seal off a dodgy sticky 8 $ bearing and re grease it , when the certain result would be a high speed failure… Trust me. No competent mechanic ever services sealed bearings. If they stick when the outer race is turned by your finger, they are replaced.
KH has never made a bearing. Honda and Kawasaki order the same numbers from the same bearing makers. All sealed bearings with the same number, always marked on the side, are interchangable. Never pry the seal off. Unless you are curious. Then replace the bearing. It’s cheap !
Oh, and the lip of the seal keeps water out because it’s greased inside, and grease is water repellent. WD40 is a grease solvent, and will remove the grease around the seal. This allows water and dirt in. So leave your wheel bearings alone! Spray the uni off with a garden hose. Triply so if it has been near salt water, cause salt is terrible. But leave the bearings alone until they feel sticky. 
Ok, cheers man. I’ll save myself the effort next time!!
I guess my desire to service something on the uni took over, as my mountainbike needs a lot of attention after a good mud bash 
Except the ISIS hub bearings, which are an odd for KH, Nimbus and Qu-ax ISIS hubs. I don’t know if you can get hold of them from a standard bearing place, I have a feeling they were ordered as custom sizes from somewhere.
Joe
i suggest soakage in WD40 or petrol it eats all the crap outta them, then if the covers are removabl and you cen get to them to put grease on them, well do so also if you put grease aroudn the gaps it will water proof the bearings, but quite abit is needed for that
I couldn’t find the torker size
So maybe torker special orders them. I don’t know why they would want to use a non standard size, but they do.
Here is a link for KH bearings. Why would you want to spend an hour screwing around getting solvent and grease on your hands when a new bearing is 2$ ?
In the past I believe it was a pain in the @$$ to get ahold of the Torker bearings. You had to go directly through the supplier in Seattle.
UDC sells them now for $15 each: http://www.unicycle.com/shopping/shopexd.asp?id=1001
UDC says the size is 21X40, which I guess is 1 mm larger inner diameter…
Hmmmm
I can’t find a bearing house that has 22x42 either. This is the ISIS size. Maybe they do this to open another revenue stream. They get the bearing maker to whip up a batch in a unique size for 1$ each. Then their customers must order it from them at many times as much. I can’t think of another reason to not pick a common size, like the 05 KH used. Oh well. So now it’s 8$ for a ISIS bearing instead of 2 $, and worse, you won’t find it locally.
Thankyou for all your advise and great response, I never exspected so much from the questions I asked.
I notesed that when I banged my wheel set on the ground quite abit of water came out from behind the ruber seals ie. from around the berrings. This making it clear water had found its way in. After reading all the posts, Against most advice, I flicked out the seals, cleaned up the berrings, sprayed them out with an air compressor then mixed up some good quality waterproof grease repacked them and slipped the seals back. I havnt bin out on it much as I had a high speed downhill mountain board accident and I am now lacking skin and movement but I believe my wheel spins more freely than ever before and seeing as I didnt damage the seals is in a better state than before.
I learned a lot to, I was sure I Knew it all
I have replaced 100’s of these things over the last 30 years. Mostly in motorcycles. Always the bearings were of a standard size and number. I think it’s a bit of a crock of SH&$ that there is a mysterious need for a unique size bearing in a unicycle. Pile of crap that the motorcycle industry doesn’t have to deal with. That motorcycles can be built in all sizes and purposes for all recorded history with standard bearings, and yet uni’s need a unique size bearing is a plotted rip off. We are being jacked deliberately.