TOPIC:

Pretty sure that's a 1977 kz650 C1 with the mags, dual front discs and round master cylinder ??..... and if it does take 2 bearings instead of 4 it seems like it would have a step where the bearing would stop when you put it in the swingarm ?.... maybe thats why , the inner two are jammed up from it ...... not sure I've had mine off and cleaned and re packed em but never took em apart.

Edit......I just looked up swingarm parts at Partzilla and they showed the 77 C1 with the bronze bushings and not bearings..... maybe some one changed em out ?

The needle bearings were a upgrade. When I did mine back in the day, they were pricy and new. I went with the bronze. 30 years later, I'm due for new ones. If my swing arm mod works out I won't have to. It has double needles in it already.
Steve

That's what I was thinking Steve and maybe the guy that changed em out went with 4 instead of two like your suppose to ??? I know my 78 has em from the factory but have never taken them out.

Old saying, pay me now or pay me later.
Steve

KZB2 650 wrote: Pretty sure that's a 1977 kz650 C1 with the mags, dual front discs and round master cylinder ??..... and if it does take 2 bearings instead of 4 it seems like it would have a step where the bearing would stop when you put it in the swingarm ?.... maybe thats why , the inner two are jammed up from it ...... not sure I've had mine off and cleaned and re packed em but never took em apart.

Edit......I just looked up swingarm parts at Partzilla and they showed the 77 C1 with the bronze bushings and not bearings..... maybe some one changed em out ?

My bike is the 78 b2

Ok no problem but if you want you could goggle the 2 models and look at the pics and descriptions. I have a 78 b2 with spoked wheels, single front disc, drum rear etc........ Assuming this but......(If the bike in your profile is not your bike then never mind)

And my Clymer and factory shop manual does show 4 bearings for the 78 KZ650 b2..

But hold on now! The needle bearings in the bikes swing arm are delicate little buggers.

First, let gets one thing strait. The pivot tube will when fitted be squeezed fixed in the frame when you tighten the swing arm bolt. Therefor we need bearings that will let the swing arm to pivot around the swing arm bolt.
So the swing arm which is made of ordinary steel is not hard enough to act as a racer for the bearing, therefor the needle swing arm bearing is fitted with an outer racer made of hardened steel and leaving the needles open on the inside. The needles are then supposed to use the pivot tube as the inner racer, there for the pivot tube is also hardened.

So when replacing them you need to dismantle the swing arm, pull out the old bearings, clean everything including the inside of swing arm tube.

Check the old pivot tube for rust, wear and pitting where the needles has been riding. If pitted or badly worn you will need to replace the pivot tube otherwise the life span of your new bearings will be short.

When everything is clean you try to fit the bearings on to the pivot tube in order to make sure they fit, they shall slide on nicely without use any force and you should be able to rotate them without force.

When you are certain they fit you can pull them of the pivot tube and fit the bearings in to the swing arm. Again no real force shall be needed, just a lite tap with a plastic hammer. You can use one of the old bearings as a mandrel. If they get stuck you haven’t cleaned out the swing arm tube properly. Pull out, re do it right and start again.

Whacking the bearings or pivot tube in place makes me curious about what profession you are in.

Needle bearings should always be handled with care, they are as fragile as your best friend.

/A

Well put
Steve

Well I bought new bearings again and gently put them in by using a threaded rod,nuts, and washers. I made sure the bearings slid on the sleeve before installing them but once again when I get the bearings in the sleeve only goes in like 2 inches and then stops. Wtf seriously Idk what to do anymore it's not going in

Grease, wiggle, turn, wiggle, turn.
And you are sure the pivot is not damaged? Or still some thing in the swing tube?
/A

Sounds like it. Spacer too long? Does the pivot bolt go through smoothly?
Steve

swest wrote: Sounds like it. Spacer too long? Does the pivot bolt go through smoothly?
Steve

The bolt is not the problem it's the sleeve I think. It won't rotate in the swing arm around the bearings. If I tighten down the pivot bolt then lift up the swing arm, it'll stay up. My understanding is it's supposed to move freely