Wildguzzi.com
General Category => General Discussion => Topic started by: Rough Edge racing on January 08, 2017, 05:38:26 AM
-
Since the 1970's almost all bikes were using tapered roller steering stem bearings...Recently, around 2005, many sports bikes have changed to caged ball bearings...This includes some or all Ducati models, Triumph and many Japanese machines...I don't know about Guzzi...
Why the change? Is it for steering feel? Or following racing trends? It seems to me the tapered rollers offer more contact area than caged balls so it doesn't appear to be a durability issue????
-
Cost and, theoretically, less resistance to motion and therefore steering precision.
-
By the time those ball bearings have created a notch in the races, the bike is well out of warranty. Not a problem....for the factory.
-
Maybe the engineers also wanted to lessen the maintenance errors, cadged bearings are set by spacers, tapered are set by feel and experience
-
And there is no fun in it if they are caged. I like back when they would all drop out on the floor and you had to chase then around.
-
And there is no fun in it if they are caged. I like back when they would all drop out on the floor and you had to chase then around.
Just changed them on my Breva.
(http://up.picr.de/27958687rp.jpg)
Caged, no fun :azn: They are less sensitive if adjusted too tight, I think as well that manufacturers
want to avoid maintenance / adjustment errors.
Happy new year to everyone :boozing:
Kai
-
Maybe the engineers also wanted to lessen the maintenance errors, cadged bearings are set by spacers, tapered are set by feel and experience
On many Showa forks with roller bearings, the bearing preload is set by measuring pull on a fork leg with a scale. I have done it on my Buell and Ducati 900M.... But as you say there is a risk of error by those not following procedure...
-
I forgot about the loose balls and was only thinking of tapered with the wide range of adjustment so that throws my theory out. Maybe in a production line it's faster with the cadged.
-
Both ball and taper roller bearings in a steering application have to absorb radial as well as thrust loads. As such they both require a bit of care in setting the proper preload. In the steering application you will not see the ball bearing preload established with a spacer. It is usually radial bearings (like Guzzi wheels) that have their spread established with a spacer. All they require is an equal spacer for the inner and outer race, or clamp one and float the other. Guzzi wheels clamp inner races on the axle and float (a bit) the outer races in the hub. Bet ball bearings are cheaper to manufacture.
-
I installed a grease fitting in the head tube of my Kawasaki H2 when I got it, which was in 1978. I've kept the ball bearings greased since then, and it still feels like new. This leads me to believe that lubrication is far more important than bearing type in that application.
-
They are caged so that they cannot run away.
-
I don't know why caged, un-caged or tapered. Caged are definitely easier to work with.
My ST1100 (1990 to 2003, 750 lb. 100hp/74'lb torque) came with the same caged ball bearing part num. as a 250cc/350 lb. dirt bike. I usually think Honda engineers know their stuff. My conclusion is the bearings aren't that big of a deal. Change them out when you think they're bad.
-
While on the subject of bearings, have you heard of the greaseless ball bearing?
http://newatlas.com/greaseless-ball-bearings-coo-space-adb/37689/
-
They're claiming the only reason ball bearings need grease is because of the cages? That's ridiculous.
-
While on the subject of bearings, have you heard of the greaseless ball bearing?
http://newatlas.com/greaseless-ball-bearings-coo-space-adb/37689/
To quote "a groove in the outer race" ????
That sounds like a failed bearing to me :undecided:
-
I replaced the original roller bearings in the steering neck of the 84 Cali I owned.....Do the newest Guzzis still use rollers?
-
I replaced the original roller bearings in the steering neck of the 84 Cali I owned.....Do the newest Guzzis still use rollers?
My 1994 California and my 2004 EV both are tapered rollers.