HBOL and head bearings.

So,

I've just gotroundto fitting the new head bearings [1] in this 86
GPz550 and I believe the only reference I have (the HBOL) tells me to:

1) Torque the first adjuster nut (castellated ring) down to 29 ft/lb
[2]

2) Check the steering moves smoothly end_to_end and with no tight /
loose bits.

3) Back off said nut till it's fairly slack.

4)Tighten it back up until you *just* start to feel some resistance in
the steering movement.

5) Fit the other nut/ring and lock them together .. etc

Now 2-5 seem pretty reasonable but I'm not sure of the point of 1)
(assuming it's correct in the fist place). Is it to ensure all the
races are fully seated?

[1] I can't remember ever changing taper roller headset bearings
before.

[2] HBOL talks of making a torque wrench from a 'C' spanner [3] and
spring balance. Luckily, car mechanic mate happened to have some
special 4 pronged 'tool' for some car lower ball joint or summat that
I thought might fit (and it did, perfectly) and a 35mm 1/2" sqdr
socket to suit. ;-)

[3] A couple of double ended C spanners on their way from the net.

 

Yes, pretty standard with any bearings that you have adjustment on [1]
& have a locknut/split pin, especially taper roller bearings.

Tighten it tight, spin it once, and back it off, just nipping it back
up gently to take up the slack.

Cheers,

Paul.

[1] i.e. not a radial ball or roller bearing

 

Brilliant, thanks.

I just felt a bit uncomfortable going to 29 ft/lb considering they
were tapered rollers (or any active bearing and as opposed to a plain
bush for that matter). It seemed an ideal way to 'pre notch' the
bearings but I assume (hope) they are too hard for that and will
probably get that sort of pressure and more in normal use?

I even heard a 'click' and that could either have been something
settling down or numerous other things. :-(

 

Not with 29 lb/ft. That's a reasonably gentle pull on a 3/8 breaker
bar.

80 lb/ft (a good pull on a 1/2" breaker bar) is tight.

Considering where they are (headstock) there's a much better chance of
notching it by hitting a pothole at speed, rather than when
installing !

Cheers,

Paul.