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1Back to top Go down   Steering Head Bearing Keep Coming Loose Empty Steering Head Bearing Keep Coming Loose on Tue May 12, 2015 2:14 pm

bettyswolloks

bettyswolloks
active member
active member
Hey All, as the title says. The steering head bearing keep coming loose on me, never had it happen to Me on any of the other bikes I've fitted new bearings to in the past, the once or twice after fitting is normal but this K is doing it constantly. The next time I do it it's going to be around the 6th maybe 7th time!!

Slacken off the pinch bolts and the top yoke nut then get a grip of the big knurled cover underneath the top yoke and tighten, finish by tightening everything back up.

Am I missing something?

http://ranfog.co.uk
    

92KK 84WW Olaf

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Did you do a head bearing job recently and maybe the bottom bearing isn't fully seated or the top bearing is not fully seated downward? I have had that happen on a bike years ago. Methinks the most likely cause.

The alternative is triple tree coming apart, check that when you are tightening the knurled nut that its not pulling the tube out of the bottom yoke. It's unlikely and shouldn't happen though....unless you get a less than expert machine shop to pull the whole lot apart.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011171 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 37,190 miles
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles.
    

Crazy Frog

Crazy Frog
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@bettyswolloks wrote:
Slacken off the pinch bolts and the top yoke nut then get a grip of the big knurled cover underneath the top yoke and tighten, finish by tightening everything back up.

When you slack the pinch bolts, are you sure that the fork tubes can freely move into the top tee?
My way to do is:
slack the top yoke nut(#4). Remove the two pinch bolts(#6) and insert a wedge (A screw driver works) in the slots (both sides). The top tee should be able to move up and down freely.
Adjust the big knurled nut(#7) and tight the top yoke nut(#4).
reinstall the two pinch bolts and this should be OK.
The knurled nut is kept in place by the pressure of the top tee on it. If the fork tubes are binding on the top tee, you may not be able to push the tee far enough on the knurled nut.

Also, check that the center tub is not coming apart from the bottom tee.

Steering Head Bearing Keep Coming Loose Triple10


__________________________________________________
Steering Head Bearing Keep Coming Loose Frog15Steering Head Bearing Keep Coming Loose Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

BooG

BooG
Platinum member
Platinum member
I have just done my steering head bearings! The biggest challenges were getting the front mudguard off: bolt and nut had rusted on, and, I managed to strip the thread of the soft ally brake pipe union with the banjo! Gonna do a thread repair shortly and see if that solves it! I've heard it said that "slightly tighter" is better than "slightly looser" re adjustment? While I'm here, does anyone happen to know the thread size of the banjo bolt in question?
Thanks.

    

BooG

BooG
Platinum member
Platinum member
Thread repair size is what I'm actually after, if that wasn't clear!
Shocked

    

sidecar paul

sidecar paul
Life time member
Life time member
The K brake fittings are threaded M10 x Imm pitch.

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

BooG

BooG
Platinum member
Platinum member
Thanks! Is the thread insert I need a M10x1 spec?

    

sidecar paul

sidecar paul
Life time member
Life time member
Yes.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

Crazy Frog

Crazy Frog
admin
admin
Standard 10mm is 1.5mm pitch
Standard fine thread 10mm is 1.25mm pitch
10mm x 1mm is also a standard fine thread but not as common as the 10 x 1.25
It may be difficult to find a tap.


__________________________________________________
Steering Head Bearing Keep Coming Loose Frog15Steering Head Bearing Keep Coming Loose Logo2101986 k75, 1985 K100rt, 1985 K100rt/EML GT2 sidecar, 1999 K1200lt/Hannigan Astro Sport sidecar.
    

RicK G

RicK G
admin
admin
I would not use a thread repair insert on anything to do with the pressure circuits of a brake system, it's looking for trouble.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

Dai

Dai
Life time member
Life time member
BooG - PM me. I've got a good condition headstock brake pipe you can have. I hated the damn thing and replaced all of my lines with braided hose that runs outside the headstock.


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

K75cster

K75cster
Life time member
Life time member
@Crazy Frog wrote:
@bettyswolloks wrote:
Slacken off the pinch bolts and the top yoke nut then get a grip of the big knurled cover underneath the top yoke and tighten, finish by tightening everything back up.

When you slack the pinch bolts, are you sure that the fork tubes can freely move into the top tee?
My way to do is:
slack the top yoke nut(#4). Remove the two pinch bolts(#6) and insert a wedge (A screw driver works) in the slots (both sides). The top tee should be able to move up and down freely.
Adjust the big knurled nut(#7) and tight the top yoke nut(#4).
reinstall the two pinch bolts and this should be OK.
The knurled nut is kept in place by the pressure of the top tee on it. If the fork tubes are binding on the top tee, you may not be able to push the tee far enough on the knurled nut.

Also, check that the center tub is not coming apart from the bottom tee.

Steering Head Bearing Keep Coming Loose Triple10

Cf when I did this I had the forks bottomed out so as to keep everything inline


__________________________________________________
Keith - 1987 K75c with r100rt replica fairing and half of a 1984 K100rt 1992 K1100LT a blue one

The Clever are adept at extricating themselves from situations that the wise would have avoided from the outset - QUOTE from david Hillel in Out of the Earth.
    

bettyswolloks

bettyswolloks
active member
active member
Had to tighten them again today, as the mark I put in the big knurled nut is going further round I can only assume the bottom bearing wasn't fully home, even though it looked like it was. If it wasn't it must of only been by a couple of points, and I cant imagine a couple of points taking up this much space on the thread.

http://ranfog.co.uk
    

92KK 84WW Olaf

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Life time member
king youbettyswolloks wrote:Had to tighten them again today, as the mark I put in the big knurled nut is going further round I can only assume the bottom bearing wasn't fully home, even though it looked like it was. If it wasn't it must of only been by a couple of points, and I cant imagine a couple of points taking up this much space on the thread.

Don't be kicking yourself on that. The object of checking it after a bit is in case it wasn't fully seated, among other things. Far less risk of damage to the bearing too, some methods of driving them home can be heavy handed and end up damaging the new bearing. Can be scary but when you think of the pitch of the thread on the nut even a quarter turn feels like a lot but in fact is very little.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011171 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 37,190 miles
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles.
    

Dai

Dai
Life time member
Life time member
There's a knack/procedure for fitting taper rollers, assuming you haven't bought/made the tool for doing it.

The first one is to tap the outer race in as far as possible, then fill the inner race with grease. Reassemble everything as necessary (in your case, refit the yokes), tighten it down until you think its fully home, then give it another 1/8th turn; no more than this because you don't want to brinnell the outer. You'd be surprised how often there is still movement in the outer race. Continue until you are certain that there is no more movement, then back off gently until you have free movement but no play.

The other is to save an outer race from the previous bearing change and use that as a drift. There is a complete and distinct change in tone when the new outer race seats correctly. If you want to make life really easy then weld a bar across the old outer race and weld a handle to that. Voila - a factory tool for the sake of spending half-an-hour, rather than half a fortune.


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

BooG

BooG
Platinum member
Platinum member
bounce Thanks for all the advice so far! Regarding the thread repair on the brake circuit; I'm gonna wrap the thread on the banjo bolt with ptfe tape, as well as the insert itself. If it leaks, then its "get a replacement" time! Won't be able to do it till next Saturday now so I'll tread water till then.

    

BooG

BooG
Platinum member
Platinum member
Some research tells me it is Ok to use ptfe on brake circuits. It will not brake down on contact with DOT4, and will resist temperatures well above what a caliper will subject it to.

    

RicK G

RicK G
admin
admin
Some experience tells me not to use PTFE on any brake circuit, It can and usually does break up and foul the seals and cause leaks which ultimately lead to failure.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki
    

Dai

Dai
Life time member
Life time member
I'm with Rick. Sufficient pressure and the whole lot will just fly straight out.


__________________________________________________
1983 K100 upgraded to K100RS spec, 1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

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