Steering head bearings

[Rod.s]

This topic came up on Facebook and will be lost to the either in two weeks so I'm sharing it here..
Yamaha and almost all other manufactures use/used crowded balls in the steering head for over a hundred years and there is absolutely nothing wrong with them, if (like any bearing) they are serviced.
Tapered bearings are being used for a select few bikes due to the ease for manufactures to install them and they come from the manufacture already greased for the intended use.
Tapered bearing are a radial caged bearing that is, by its design intended to spin, not sit still or rotate 20-30deg back and forth. What happens is the needle sits in the one place and chatters on the outer race causing it to wear a groove, resulting in notchy feel through the bars, manufactures love this as there is no service schedule apart from replacement, money in their pocket.
Crowded bearings move around the race as they are not confined by a cage so will not create a divot etc- If serviced as per the manual
so clean and polish the race with 2000 grade paper and some metal polish and fit new balls, they are dirt cheep. Use water proof grease and adjust as per the manual.

[osbxrt]

I haven't seen crowded ball bearings used for ages,[except on push bikes] These have mostly been replaced on UJMs by OE 'caged Angular Contact bearings' which are still in use on some of my motorcycles now, TRX included.

[Snod Blatter]

The original bearing on a TRX keeps the "loose" balls in place with a plastic cage, the worst of all worlds!

Personally I'll stick to tapers, they don't seem to wear and I definitely am not servicing those bearings any more than is strictly necessary. Why aren't there a grease nipples on the headstock anyway?

[cobbadiggabuddyblooo]

So why is it the worse of all??
In what situation???
It's job is purely retain the balls because the balls sit against each other laterally and the cup and cone will surround the balls in all other directions. there is no integral pressure upon the plastic cage correct???
The steering head bearing wouldn't move at any great speed so heat would not be an issue????

[Rod.s]

Crowded balls are still used on most modern bikes even the GP bikes use them, even the latest MT09 uses them! Taper bearing were never used on the TRX by Yamaha

[Snod Blatter]

Oh dear, I seem to have enraged the fanatics Here are the original bearings, note how the balls are held in place:

"Crowded bearings move around the race as they are not confined by a cage so will not create a divot etc- If serviced as per the manual" - How are these supposed to move around the race??

[cobbadiggabuddyblooo]

No not enraged, just wondering why the plastic is worse of all???
I’d assume heat would be an issue to cause issues with plastic cages but wouldn’t be an issue here???
Maybe steel cages aren’t nessesary like a grease nipple???

I suppose it’s each to their own or prevention is better than cure.

[osbxrt]

Crowded balls are still used on most modern bikes even the GP bikes use them, even the latest MT09 uses them! Taper bearing were never used on the TRX by Yamaha

Thats right, they are called Angular Contact bearings and were fitted as OE on the TRX850, they are not taper rollers.

[Trx envy]

So, whats the oral of the story? That its easier and cheaper to service the existing bearing than whack a new one in?

[cobbadiggabuddyblooo]

Yes, in my eyes plus their design fits the purpose.
That’s why Yamaha use them.
Mechanics now days get very little time to complete a full service so things like re packing the grease in you steering head bearings becomes.
Oh your steering head bearings are stuffed and you’ll need to book in to have them replaced to rack up another couple of hundred $$$ from you.

[Rod.s]

Crowded balls are still used on most modern bikes even the GP bikes use them, even the latest MT09 uses them! Taper bearing were never used on the TRX by Yamaha

Thats right, they are called Angular Contact bearings and were fitted as OE on the TRX850, they are not taper rollers.

Are yes too true, my mistake