'81 GPz steering neck bearings, any tips?

My bearings are shot in my '81 GPz550, I've ordered a set of tapered bearings to replace the standard ball bearings in the steering neck.

I will follow the service manual and have access to a lift and my brother who has been working on bikes for over 40 years so I hope things will go smooth.

Any advice or tips for this specific application?
The kit I ordered was from All Balls Racing.
Thanks!

They're good quality bearings. Unlike ball bearings you need to set preload. Not much and you'll notice they will get loose as they settle in. Just adjust it again and you'll be good for a long time.
Steve

Yes. that is a good kit. I have them in all my bikes. But it is critical to set the axial play correctly. On my first set, I had them a bit tight and the rollers left notches. Removing the races from taper-roller bearings is a bitch and a half, so get it right, and you may never have to replace them again, hopefully.

Remove any wiring and cables etc. Jack up the front of the frame and make sure nothing impedes the rotation of the steering. Then set it for ideally zero play or slightly loose, since it will tighten when locked down. Then lock it down per manual, and double check there is no additional drag in the rotation. Rotate back and forth a few times to work the grease and check again. When everything is torqued down, and there is no play, but still freely rotates, it should be good. After installing the forks and wheels and riding a bit, it may loosen up a bit, so go through it all again in a few months (just as Steve mentioned).

But you cannot judge the rotation freeness with cables and wires, so it's a long process to remove them and re-install them. I learned the hard way, and had to spend a better part of a day removing the bad taper races with a dremel. If I had to remove them again, I'd probably weld a pipe to the race and bang them out.

(Obviously, the stock ball-races just pound out like the manual says.)

I put an All Ball's kit in my 750E but there was no upper seal. I wound up taking a spare lower seal and putting it on the top as well to create a seal but I'm not sure why they don't include a seal out of the box.

Same here. I think I reused the old seal.

Well my kit came with both upper and lower seals, so far so good on the install. Everything came apart without much of a fight and thanks to the lift the forks and wheel were able to stay together. It was amazing how bad the ball bearings felt once the weight was off and all the cables were removed, the was a HUGE notch right in the middle and it required a fair bit of effort to overcome it while just grabbing the trees.
The old races came out without much fuss and we got the neck cleaned up and the new races pressed into place, at that point it was freezing in the garage and getting dark out so we called it a day. I hope to have it reassembled tomorrow as long as I didn't get pneumonia from the ride out to my brothers when it was 34 degrees :ohmy:

MadShad wrote: Well my kit came with both upper and lower seals, so far so good on the install. Everything came apart without much of a fight and thanks to the lift the forks and wheel were able to stay together. It was amazing how bad the ball bearings felt once the weight was off and all the cables were removed, the was a HUGE notch right in the middle and it required a fair bit of effort to overcome it while just grabbing the trees.
The old races came out without much fuss and we got the neck cleaned up and the new races pressed into place, at that point it was freezing in the garage and getting dark out so we called it a day. I hope to have it reassembled tomorrow as long as I didn't get pneumonia from the ride out to my brothers when it was 34 degrees :ohmy:

You are lucky that "notch" did not give you bad case of tank slappin' head shake!!

The 81 Gpz550 gets a pretty noticeable headshake when accelerating hard over uneven surfaces, especially since the front end gets very light on hard acceleration. That is not like a tank slapper, which is a resonant oscillation, but a head shake is a single violent jerk one direction or the other, and possibly followed by a second swing or two as the steering recovers. For this, a steering damper is used. But in order to use the steering damper, the steering rotation has to be limited (as they are in modern sport bikes).

If you are considering a steering damper, now is the time to install a larger stop for the steering.

I would not ride a gpz hard without it.

Here is the stop I add. The set screw is only to hold it in place while welding. The set screw will not hold it in place by itself, permanently.

On this bike I used the steering damper that came on the 2 strokes. They still sell them brand new.

Loudhvx, looks like a great solution. I think it would be overkill for the way I plan to use the bike but good to know. I'd like to think that I'll ride with more sense than what I did when I was younger, we shall see.

I did get the bike buttoned back up yesterday, took a short test ride at speed then went and did some low speed tight figure eights in a parking lot and it felt much better!

I can see how getting those tapered races out of the neck would suck, I'll be sure to recheck after I put some miles on it.

love your exhaust set up. what muffler is that?
I have a mac 4 into 1 header I'll be using and am looking for a similar muffler.

MadShad wrote: Well my kit came with both upper and lower seals, so far so good on the install. Everything came apart without much of a fight and thanks to the lift the forks and wheel were able to stay together. It was amazing how bad the ball bearings felt once the weight was off and all the cables were removed, the was a HUGE notch right in the middle and it required a fair bit of effort to overcome it while just grabbing the trees.
The old races came out without much fuss and we got the neck cleaned up and the new races pressed into place, at that point it was freezing in the garage and getting dark out so we called it a day. I hope to have it reassembled tomorrow as long as I didn't get pneumonia from the ride out to my brothers when it was 34 degrees :ohmy:

carwash wrote: love your exhaust set up. what muffler is that?
I have a mac 4 into 1 header I'll be using and am looking for a similar muffler.

I've got no idea, it was on the bike when I bought it.
I don't even know what header I have, I can tell you the tip on the yosh can isn't perpendicular to the ground the way its setting and it bugs me a little. That little detail is at the end of a growing list of things to do!

Cool. Any chance you could post or pm me a full side pic of the bike?
Thanks!

MadShad wrote:

carwash wrote: love your exhaust set up. what muffler is that?
I have a mac 4 into 1 header I'll be using and am looking for a similar muffler.

I've got no idea, it was on the bike when I bought it.
I don't even know what header I have, I can tell you the tip on the yosh can isn't perpendicular to the ground the way its setting and it bugs me a little. That little detail is at the end of a growing list of things to do!