Head Tube Bearing Replacement - Front End Maintenance

[smokey9lives]

Hi,

I have a 2003 DRZ (actually a KLX400) and the head tube bearings are shot.  I ordered a new set to install but I'm wondering if anyone has any recommendations on other parts I should replace while I have the front disassembled.  I was thinking about new rubber fork protectors, but are there other things that wear out on the DRZ front ends that you can only get to when disassambled?

I also broke off a replacement key that I got for the steering lock.  I must have been made of cheap pot-metal.  Should I just remove the whole lock mechanism?

Any tips or tricks for getting the old bearings out and the new ones in would be welcome!

Thanks!

[74jimbo]

Interested in this also. I don't know that my head brarings are bad, but I do have a set of all balls head bearings that came nib when I got my bike

[smokey9lives]

1 minute ago, 74jimbo said:

Interested in this also. I don't know that my head brarings are bad, but I do have a set of all balls head bearings that came nib when I got my bike

Yeah, all balls is what I got in the mail today!

[74jimbo]

I have actually heard that all balls is blah in quality.... so only time will tell if I put them in.... there is no better than oem

[GuyGraham]

The bearings are easy (ish) to replace

The top bearing will come out no problem as it is a loose fit in the frame and on the stem

The bottom bearing can be a bit more of a challenge. You need a long drift to insert into the top of the frame, down onto the bottom outer race and knock it out with a hammer

The  bottom inner race is difficult to remove from the stem. the best way is to use an angle grinder and grind a flat on it almost through to the stem. Then a qucik sharp blow wit h a hammer will cause it to break and it will drop off. Trying to knock it off is almost impossible

 

Fitment wise, is a question of warming the bottom bearing (in the oven for example) and it will just drop on. Fitment of the bottom outer race into the frame is easier if you freeze it in your freezer and then fit it to the frame

[Erik Marquez]

1 hour ago, GuyGraham said:

The top bearing will come out no problem as it is a loose fit in the frame and on the stem

Then your frame was worn/damaged. The bearing outer race is press fit on both top and bottom in the same press fit clearances. When the bearings are run loose, it is the top one that takes the biggest hammering and that does "stretch" the frame at the bearing race fitment.  Using a product like Loctite bearing mount 680 would be a good idea if you find the steering head bears race is not a tight fight (tight= equal on both top and bottom if you have no other reference in how they should fit)

[Erik Marquez]

6 hours ago, smokey9lives said:

Hi,

I have a 2003 DRZ (actually a KLX400) and the head tube bearings are shot.  I ordered a new set to install but I'm wondering if anyone has any recommendations on other parts I should replace while I have the front disassembled.  I was thinking about new rubber fork protectors, but are there other things that wear out on the DRZ front ends that you can only get to when disassambled?

I also broke off a replacement key that I got for the steering lock.  I must have been made of cheap pot-metal.  Should I just remove the whole lock mechanism?

Any tips or tricks for getting the old bearings out and the new ones in would be welcome!

Thanks!

There are no other "must service" items just because the steering head bearings are being done... As you will have the front end apart anyway, you might take the time to service the forks, check the wheel bearings and seal, ect.

Steering head lock are only there to stop honest people from being dishonest, they are snapped off with a good swift kick or otherwise forcing the bars. That said, theft prevention is about making the bike more irritating to steal then the one down the street...because if the thief wants yours or both yours and the one down the street, they are taking both.  So replace that lock, keep it lubed and use it along with other deterrents.

To remove the lock normally you need the key....if you can still turn the lock cylinder with the broken key in it, your good, if no key or it will not turn, it will need to be drilled out and NOW with the steering stem out is a great time to do that so the bearings are not contaminated with cutting fluid and swarf

[GuyGraham]

36 minutes ago, Erik Marquez said:

They your frame was worn/damaged. The bearing outer race is press fit on both top and bottom in the same press fit clearances. When the bearings are run loose, it is the top one that takes the biggest hammering and that does "stretch" the frame at the bearing race fitment.  Using a product like Loctite bearing mount 680 would be a good idea if you find the steering head bears race is not a tight fight (tight'= equal on both top and bottom if you have no other reference in how they should fit)

Was going from memory as its a long time since Ive done head bearings and never on my drz as i keep them well serviced so they dont fail from water ingress

Makes more sense for the top outer race to be an interference fit in the frame though.

[Erik Marquez]

44 minutes ago, GuyGraham said:

Was going from memory as its a long time since Ive done head bearings and never on my drz as i keep them well serviced so they dont fail from water ingress

Makes more sense for the top outer race to be an interference fit in the frame though.

Id say even chance your memory is spot on its not all that uncommon to find the upper race a looser fit on a well used bike. But its not by design, just wear and use.

[jjktmrider]

8 hours ago, smokey9lives said:

Hi,

I have a 2003 DRZ (actually a KLX400) and the head tube bearings are shot.  I ordered a new set to install but I'm wondering if anyone has any recommendations on other parts I should replace while I have the front disassembled.  I was thinking about new rubber fork protectors, but are there other things that wear out on the DRZ front ends that you can only get to when disassambled?

I also broke off a replacement key that I got for the steering lock.  I must have been made of cheap pot-metal.  Should I just remove the whole lock mechanism?

Any tips or tricks for getting the old bearings out and the new ones in would be welcome!

Thanks!

If you have easy access to a MIG or TIG welded you can do a quick weld bead on the inside of each outer bearing races in the headstock and they'll slide out without a punch or drift needed . It's sometimes an easier method if the headstock bearing stop inside completely blocks the race from being punched out normally, or easily . If there is good access to the outer race a punch or drift (or better yet ,puller) is the preferred method . Anytime I have the races out I take a die grinder and put a couple notches in the stops to allow good access to the races with a punch the next time .

 

.

Edited October 14, 2018 by jjktmrider

[Erik Marquez]

22 minutes ago, jjktmrider said:

If you have easy access to a MIG or TIG welded you can do a quick weld bead on the inside of each outer bearing races in the headstock and they'll slide out without a punch or drift needed . It's sometimes an easier method if the headstock bearing stop inside completely blocks the race from being punched out normally, or easily . If there is good access to the outer race a punch or drift (or better yet ,puller) is the preferred method . Anytime I have the races out I take a die grinder and put a couple notches in the stops to allow good access to the races with a punch the next time .

 

.

The DRZ frame has a bearing shoulder smaller in diameter than the bearing, ....not sure I have seen a frame otherwise actually. Yes some with less overhang then others, but they all have one as far as I remember..
You do need a race punch or drift with a good square edge to it....or a puller of the right size. So dress up that 1" brass drift or your nice shiny snap on race punch before you start hammering 

[jjktmrider]

No kidding ?? .

 

.

[Erik Marquez]

2 minutes ago, jjktmrider said:

No kidding ?? .

 

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Perhaps im forgetting the bike model that has a shoulder larger then the bearing and leaves no access to the bearing race for removal? Thats for sure possible. Or your thinking of a bike I have never worked on, lots of those too..

So just referring to the ones I have done steering bearings on (and that would not be but a fraction of all the bikes modes I have had come though the shop..so its very possible many of those had the issue you have seen)

Its something I'll pay attention to though now..even if not replacing the bearings but have the lower triple out.