Just in the process of replacing the head bearings on my 1979 GS750, but could use some advice. I ordered a set of All balls bearings, but have been scratching my head a bit !. I assumed the top and bottom races are the same, but the packaging for each bearing have different numbers. The set number is 22-1005, but one bearing pack has on it 99-3505-1 while the other is 99-3508. The dust seals both have the same number 33-1006. Just made me wonder if one bearing is for the top and the other the bottom, or whether they are the same. No instructions with the kit, but says info on installation on their website, could'nt access for some reason though. So, just wondered whether anyone has installed these and might be able to advise. Any help much appreciated. Oh, forgot to mention a PO had fitted tapered races before, pig of a job to get them out !.
-
Required reading for all forum users!!!
Welcome!
Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.A note to new registrants...
All new forum registrations must be activated via email before you have full access to the forum.A Special Note about Email accounts!
DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.A note to old forum members...
I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.
Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...
-
Returning Visitors
If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.
If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.
Steering head bearings
- Thread starter tomo
- Start date
I cant really say about your 750,
but on 1100G the lower set was noticeably larger diameter
(which also made it harder to knock out the lower one since was no edge accessible from the inside-top. Had to cut the inner race with a dremmel tool).
but on 1100G the lower set was noticeably larger diameter
(which also made it harder to knock out the lower one since was no edge accessible from the inside-top. Had to cut the inner race with a dremmel tool).
Bearings are different. I just googled and found the specs and for your bike they're listed as 27x48x14 and 25x48x15
Thanks guys. Just had a look at the old cups, seem to be the same outer diameter, but will have a good look at the new ones tomorrow. On my bike, there was no way to knock the cups out as at both top & bottom there is a bit of a radius of the headstock just before the bearing seats, so no way to get a screwdriver or chisel under the cups. I tried the dremel trick, cut the cup about two thirds deep then whacked with a chisel but no luck. So called a mate who is a mechanic and he came over, welded in a steel rod in the top cup then was able to knock out from below. Bottom one tried same but for some reason weld did,t hold, but he built up some weld blobs so he could knock it out using those !. So got there in the end. Anyway, I will have a good look at the bearings tomorrow, bit cold in the garage tonight, must be getting old !!. Thanks again, I,ll let you know how I get on. Any ideas on those sizes Hampshirehog, I,m guessing 48 is OD, 25 ID and the other depth ?.
I believe the stem needs a modification for tapered bearings to fit. There is a ridge on the stem which must be lowered about 6mm for the top bearing to seat low enough to allow bottom bearing to be pulled up into the lower cup.
The Z1 site has the modification details, click on "view technical documents"
The Z1 site has the modification details, click on "view technical documents"
Last edited:
Another way of removing the old bearing cups is to..... wait for it..... drill through the steering head at the angle point between the head and the cup seat. Then use a tiny drift to tap the cup out from behind. Fill the drill hole with a dab of silicon. No harm, no foul.
Last edited:
Thanks for all the advice everyone. Feeling a bit stupid this morning !. Took a look at the headstock this morning and a light clicked on in my excuse for a brain !. Pretty obvious as the stem thickens out in two places, 1" or so down from the top then at the base, the inside diameters of the bearings have to be different. So sorted out now, just have to fit them. Kept the old cups & centre piece of the old bearings to use as drifts. I read about the stem mod as well, think that must have been done by the PO as he had fitted tapered bearings. Thanks again everyone, I've been a bit dense on this one, posting before thinking things through !.
And if keeping the bike long-term, grind an access slot into the shoulder above the bearing cup, so you can get a drift in there, next time you do them and don't have a welder to hand. I've had a couple of bikes that had two access slots cut from the factory, so it's not a new or dodgy idea.
