It may be the swing arm bushing but...

I have a '78 KZ650. Lately I have noticed a weird pull to the right of the back wheel. It has been progressivly getting worse. It happens during shifting and braking. My husband and I took a look at it and he is telling me that it's probably the swing arm bushing. The rear tire has over a 1/2" of play side to side when up on the center stand. When I checked at the local Kaw dealer, I was told that each bushing was 46.99. I was also told that there were after market bearings that were 9.99, but the parts guy couldn't tell me if they were basically the same thing or not, or even if it would work on my bike. I have had the bike for over 5 years but I'm still pretty green as to alot of the mechanical workings and I know the bike had seen a few ditches and such up close and personal before I got it, so I'm kinda worried about what I may be getting into. I am soon to be tearing the rear end off to get a better idea and will follow up, but any additional info is greatly appreciated. Y'all think it's the bushing as well? Would the bearings be the same and/or cause me more to have to replace? Thanx much!

im not sure about 650s but kz1000s had double needle bearings in 78.if you are sure its the bearings it might be cheaper just to find another swingarm im sure theres plenty of good 650 swingarms on here to be had.

Wireman puts out a good idea: I went with a used swingarm and it has done me well for a year now. And it was relatively plug and play.

For the other bearings on my motorcycle, I have pulled them, did a measurement check on them with a pair of digital calipers, and searched online and at local stores for them. The measurements read: outside of the bearing, inside of the bearing, and the width of the bearing. I never did figure out if there are different "grades" or weight bering capacities, maybe someone else knows.

Good luck, you and your husband are on the right track.

Whenever you need parts it a good idea to check with Jeff at Z1 Enterprises , he is a member here and it's tough to beat his prices and service.

For instance, Swingarm bushings are $31.82 a pair (out of stock at the moment though). It's well worth giving him a call.

cherny_grrrl wrote:

...Y'all think it's the bushing as well? Would the bearings be the same and/or cause me more to have to replace? Thanx much!

Hi!
The other guys gave great advice, but I just wanted to clarify one thing I read in your post: Some bikes came with bushings, some have bearings.

And, though it may be possible to replace bushings with bearings in some cases, the internal components of the swing arm swivel will be different.

For instance, my '78 750 was the first year of the 750 twins to have bearings instead of bushings. It requires a swivel shaft that goes *inside* the bearings, and the swivel bolt goes inside the shaft.

By the way, replacing bearings can be a bit of a bear (I just did it recently), but should give good longevity when maintained. Replacing bushings seems (I've never done it) alot easier. Just keep PLENTY of grease in there! I hope your swingarm pivot has a grease nipple. If so remember to fill it with grease 'till it oozes out the sides.

About your 1/2" of play... is it just the wheel that does that or does the swing arm move with it? I shudder to think that the wheel bearings would move that much!!

Good luck...

Thanx everyone for the advice. I plan on tearing the rear end apart this weekend.. so now I have alot more info as to what it may be. As to Biquetoast's reply, I went and looked this morning and it appears to be the whole swing arm along with the wheel that's moving. But I didn't have the time to throw her back up onto the center stand and really give it a good shake. So would that make it more of an arm problem or still bushing or both?

cherny_grrrl wrote:

...So would that make it more of an arm problem or still bushing or both?

Well, the bushings are actually designed to wear. I kinda was suprised about 1/2" though. They must be pretty worn, like with no grease for a couple years...

Well, like I said, it's still kinda new to me. I'm still learning all the little things that require more upkeep than what they tell you in the motorcycle training course. Not to mention a bike that was put thru the ringer well b4 i got it. We took the wheel off this evening and the bushings are okay... the bearings tho.... ooooo bad. They are needle bearings and on the left side of the bike, the bearing's tin ring is split and open by about 3/4" and most of the rollers are broken, sitting sideways, or missing all together. Judging by the damage, it appears that when I would shift or brake, I was moving the swing arm bolt alot further than just within a worn bearing. I took a couple of pics but they didn't turn out, will try again tomorrow when there's light. It seems to have plenty of grease but it looks really "mucky" so i'm sure it contaminated at this point. SO that's all getting redone this weekend hopefully. As much as it sucks to not get to ride, I enjoy getting to work on it. So thanks everybody again! Hopefully, I won't have anymore "little things" creep in and bite me, and then I can give it a good overhaul in the off season.

cherny_grrrl wrote:

...the bushings are okay... the bearings tho.... ooooo bad...

Ok, so I finally went and looked at your bike's parts diagram on buykawasaki.com . Now I understand. Your bike doesn't have "bushings", it has the needle bearings (or it *had* bearings ) you discovered. Your '78 C2 was the first year with bearings, and the C1 had bushings. You also have a grease nipple which helps to explain why it's well-lubed.

A great place to get replacement bearings is z1enterprises.com.

Note: check the swingarm sleeve VERY closely. On mine, the lack of lube from the P.O. had detroyed the sleeve, and new bearings alone (without a replacement sleeve) would have just destroyed the bearings in short order again...

Note the parts in the picture below in little boxes, #30 and #31. Those are your bearings and sleeve, to replace parts #3 and #6 from the '77 C1....




Post edited by: Biquetoast, at: 2006/09/01 08:48

Biquetoast, you're my hero. I had no idea where to find that parts diagram. I had seen it at the Kaw dealer and was attempting to explain it to my hubby via drawings in blue sharpie.... LOL! And Thanx for the extra info, Very Very Much! The plan is to get the parts (#30 AND #31) this weekend or just after the holiday. Yippee,I'll get to ride again soon! It's been killing me....