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Discussion Starter · #1 ·
I'm noticed the steering on my 1978 K1000a is notchy. I pulled the triple tree and see wear on the race. Is there a new style bearing for this bike. The original is individual balls, with no cage. I don't see anything like that on Z1 Enterprises site.
 

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Balls with no cage is normal. A good clean and regrease should see you right (top and bottom obviously).

Fialing that, you could fit taper roller bearings. All Bslls Racing will no doubt have a suitable kit for your bike.

You’ll need a 30/48 (12) too bearing and a 30/52 (16) bottom bearing. If you can’t get the correct thicknesses (12 and 16mm), you can work around that.
 

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If David's advice does not fix the problem then likely someone has overtightened the preload nut and the balls have dented the races. An impact from a hard hit in an accident could also dent the races.

The only fix for this is to replace the races and balls or do as David suggested and look for a supplier of tapered roller bearings.
 

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Z1Enterprises has the AllBalls tapered bearing set. Z1Ent #AB22-1014.
Enter your model, choose suspension & steering, then choose steering.
Z1Ent provides the actual measurements. unlike amzn which has the very important & helpful package size measurements. and yes, that was sarcasm.

link disabled. delete the x, then copy & paste into your browser.
xhttps://www.z1enterprises.com/steering-bearing-kit-kz550-kz750-kz900-kz1000-z1.html?fits-motorcycle=Kawasaki/KZ1000%20Early/KZ1000-A2/1978
 

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I have found that the cause of many bearing failures of this type are due to lack of proper adjustment. The individual ball type steering head bearings are not ideal but also are not as bad as their reputation would suggest. The bearigs become loose allowing the steering stem to chuck and the races to become slightly out of alignment. This prevents an even distribution of load and results in point loads on just a few balls which dents the race. I have found the same type of failure in automotive differentials. Diff is whining, pinion shaft is loose due to improper preload, inspection shows the same type of damage to the pinion shaft bearing opposite the ring gear. New bearing, race, crush sleeve and proper rotational preload cures the problem. Once the damage is done replacement is necessary but for those still running individual balls keep them properly adjusted and you will likely get a long service life. One of the advantages of the tapered bearings is vastly greater contact area making them more tolerant of point loads.
 

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Excellent point gpz550. I never considered that too loose was also a bad thing but it makes perfect sense.

When I was a young apprentice learning about bearing maintenance it was impressed upon me how bad it was for ball bearings to be adjusted too tight. The cardinal rule to remember was that "nobody likes to have their balls squeezed too tight". That stayed with me for life. ;)
 

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Ball Bearings kept well lubed, and a steering stem adjusted as part of the tune up, you could get away with never changing them. Mine were still good, but the tapered steering bearings definitely gave the front steering a very solid feel. If you don't keep them lubed, and appropriately tightened, those pins will wear long channels in the race. Bearings, especially ones exposed to weather have to be maintained. ;)
 

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"nobody likes to have their balls squeezed too tight"
That depends on who's doing the squeezing! :)

The ball bearings on my Honda were mounted in a cage. I doubt you could get those, but why would you? A sheet of rubber cut properly will act as a seal, and the needle bearings packed with grease will last for longer than the bike. :)
 

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There has been some consolidation of the smaller bearing wholesalers but in our town (pop ~75,000) we still have a couple of major suppliers who keep a really good stock of bearings. It helps when you have a major oil refinery and a paper mill right in our town.

And for those less fortunate, there is always amazon.
 

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Living next to industry has it advantages. There is nothing but stores allowed in our little town of 26,000 people. You have to go out of town for everything. Thankfully, the next town over has loads of industry, and a "Graingers". ;)
 

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Discussion Starter · #19 ·
I did install the AllBalls tapered bearing setup in the 1978 KZ1000a. As far a photos, I didn't get many. After pulling the upper and lower triple trees, I used a long copper tube to knock the top race out. It popped right out - too easy. The bottom one however didn't want to come out. I ended up using a 2 lb. solid iron "chisel end" prybar to get it out. It took 1/2 an hour of careful controlled dropping of the iron pry bar (chisel end) onto the lower race that was protruding into the neck space. It finally relented. Installing the upper race went in fairly easily with some nudging from a plastic hammer. The lower one was a bit harder. Finally, I heated (not too hot) the inner side of the neck tube - coated the inside with grease, and used a socket of the same size to send the race to it's home position. The lower taper bearing needed to be pressed on to the lower triple tree shaft. I used the old "ball race, which would bear down on the inner collar of the new bearing - and not against the roller bearings or cage"" to drive the new tapered rollers down to the bottom of the triple tree shaft. I used an, "I think: 1.5" piece of pipe to slide hammer against the old race to seat the new one. I then greased the upper and lower bearing and race with marine grease, and reinstalled the triple tree - then torqued.
 

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