1981 GPz550 Steering Stem Tapered Needle Bearings Source 2025?

asphalt900 wrote:

I've never used them on a 550, only the Z1/KZ. Note the photo print of application on the SSK package. But all the aftermarket tapered bearings resulted in a slightly taller stacked height resulting in sloppy headlight ears, have to shim them Not removal of any material. But don't think your 550 has such arrangement? You might have a bracket, don't know would have to look that one up. 

Understood. Since the SSK bearing stack height is > OEM ball bearing stack height, the distance between upper and lower clamp increases and the headlight ears will not be firmly squeezed in a stationary position.

The 550 headlight ears use an odd combination of a cosmetic chrome ring on the bottom, followed by a flat washers and then a fairly thick rubber cylindrical tube 13169 shown in the fiche. If 13169 is still available I could use that to compensate for the slightly taller stack height.  

srsupertrap wrote:

asphalt900 wrote:

I've never used them on a 550, only the Z1/KZ. Note the photo print of application on the SSK package. But all the aftermarket tapered bearings resulted in a slightly taller stacked height resulting in sloppy headlight ears, have to shim them Not removal of any material. But don't think your 550 has such arrangement? You might have a bracket, don't know would have to look that one up. 

Understood. Since the SSK bearing stack height is > OEM ball bearing stack height, the distance between upper and lower clamp increases and the headlight ears will not be firmly squeezed in a stationary position.

The 550 headlight ears use an odd combination of a cosmetic chrome ring on the bottom, followed by a flat washers and then a fairly thick rubber cylindrical tube 13169 shown in the fiche. If 13169 is still available I could use that to compensate for the slightly taller stack height. 

Are your ears loose now with the bearings adjusted ? - if so you could use "O" rings as packers

As Wookie suggested, you can shim with an oring. You i believe have 35mm fork tubes so something like that. You can source those at your local hardware plumbing or oring selection store. But First have to establish if they will be required. And that is after final adjustment of bearings. I always loft the front wheel off the ground when adjusting, my personal preference. Easy enough to do if you still retain your centerstand? Use the spanner tool to tighten lock ring till turning begins to get stiff feeling then back-off till it "feels" right. A lot of times tightening the Center bolt will effect what you thought was correct so a few tries may be needed to get the results you desire. Look underneath the top bridge or triple and see if it's pressing down on adjustment bolt. If not then it Would be possible that it's backing out resulting in a progressively loose scenario. Anyway while it's where you want it, THEN check for loose headlight ears and modify accordingly.  

I did one of my 1981s in the exalted by every forum expert tapered needles. After that 100% bunch of malarkey, for nothing, I did the second one in OEM steel bearings and new races.

 

 

I don't know how you guys are having issues with tapered roller bearings, but... dang. 

So far I've done four of them - recently with All Balls bearings on a KZ440B - and they've been good. 

We've done a 79' CB 750F, 75' CB 400-4, 74' CB 550K, 70' CB 450 DOHC, 77' KZ 1000, 78' KL 250, 80' and 81' GS 1100E and maybe a couple other bikes with All Balls tapered roller bearing kits without any problems. The most important thing is getting the lower bearing stack height the same as stock. The first bike we did was the 75' CB 400-4 and I didn't get the stack height right the first time but was able to correct it. 

Disassembled the steering stem assembly and found the the lower All Ball outer race cage separated as shown. The top All Ball bearing (Lt) is not damaged and spins smooth.  I installed both Upper & Lower All Ball bearing and it was not in this condition when assembled. During the disassembly process, I checked for steering stem movement with the front wheel installed and later with just the forks installed in the triple tree. I did not feel any movement. Have removed the lower All Ball bearing from the steering stem and awaiting a couple of parts from Partszilla. 

 

 
 

 

If the bearings weren’t adjusted correctly then a bumpy road would have a “jack hammer” effect on the lower bearing which would break the cage

No one asked but I was actually questioning if I forgot to install All Ball bearing upper & lower races back in 2013. If I had left the stock Kawasaki ball bearing races installed and just installed All Bearing Needle Bearings that would explain why the lower All Ball bearing cage separated. This Saturday I removed the steering stem upper & lower races with the trusty Dremel, drift and hammer. Both races removed were marked All Ball Bearing. All the parts were All Ball bearing components.
 
Why did the lower Bearing race cage separate/fail? I am sorta stumped. If the lower bearing cage was damaged during install I would have noticed the roller cage had separated. The All Ball upper & lower races were fully seated and square in the frame. I have installed many bearings and like you know the mechanical sound of metal contact. During the 2013 assembly, I tightened and snugged the steering stem nut with a 5" spanner wrench, not with a torque wrench and spanner socket. Once the GPz 550 was road worthy, I was not practicing wheelies and it was not ridden on bumpy or construction dirt road. 
Here is a photo of the steering stem notches I made to ease disassembly next time.
 
Next weekend reassembly.

 

I’m confused, are you saying you installed taper inners to “ball race” outers ????

I was stating another possibility that could result in the lower bearing failure. The pictures show all the removed inner & outer bearings were All Ball marked parts. So much for that theory

So as previously mentioned, if there is play in the bearings every bump in the road will hammer the bearing rollers against their "stop". I guess 12 years of that was enough for it hence the broken cage. To be honest these are simple parts that either "work" or they "don't" in this application I would expect them to last a very long time if adjusted correctly (cars use this set up for wheel bearings and go for years without issue)