what the heck--my bike is pisssed

[FROSTY]

Ive never encountered this problem before.
As Im riding along on a straight bit of road the bike wobbles -its a slow wobble and isn't like a flop from side to side but a definite wobble. The steering head bearings seem ot be either stuffed or overtight and the rear disk is definitely bent
any ideas?

[merv]

Are your rims absolutely straight and the tyres on absolutely straight as well? If not that can cause the effect you are talking about too.

[FROSTY]

I only just aquired this poor ol beast so Ill add those to the list to go through--TY merv

[FzerozeroT]

when was the last time you're tyres were balanced?

[Posh Tourer :P]

there's one at each end, thats balanced....

[FROSTY]

when was the last time you're tyres were balanced?
Dunno--as I said -I just got the old beasty but ill add that to the list of possible problems

[Mr Skid]

Try riding it in the gutter.
By removing one phase of the waveform it'll only wobble half as much. :niceone:

[Blakamin]

or take one wheel off...... surely if ya dun a rollin stoppie or a wheelie youd no which wun was wobblin :eek: :msn-wink:

[sedge]

Check for play in the swing arm bearings... you get more of a weave than a wobble from that though...

cheers,

Sedge.

[Bonez]

Check ya wheel bearings.

[riffer]

Ive never encountered this problem before.
As Im riding along on a straight bit of road the bike wobbles -its a slow wobble and isn't like a flop from side to side but a definite wobble. The steering head bearings seem ot be either stuffed or overtight and the rear disk is definitely bent
any ideas?
Far be it for me to try and diagnose YOUR steering problems Frosty, but how tight is the steering?

When I overtightened my steering head bearings I got a similar result - it felt like a pillion on the back, rocking slowly left to right.

Rear disc bent? Should only give a shudder when you push on the brake with your foot...

or do you mean the back wheel? If that's bent, replace the sucker fast!

I would regrease the steering head, and torque down to the correct specs.

But what do I know? It all sounds suspiciously like my problems all over again... :(

It doesn't go 'click' when you loosen it off too does it?

[FROSTY]

When I get my racebike sorted out etc im gonna get into it.
I think the problem is super tight steering head bearings

[riffer]

When I get my racebike sorted out etc im gonna get into it.
I think the problem is super tight steering head bearings

Yes, but WHY are the bearings super tight?

Could be because its hiding something...
:disapint:

like worn race sockets.

Then again, it could just be because all the grease has dried up and the bearings are full of rust.

[FROSTY]

or -the previous owner was a total FU#@#@ and had no idea what he was doing. :angry2:
my poor ol baby

[F5 Dave]

Head bearings that are damaged even slightly will cause this effect. You can take them apart & look at them, oh yeah they’re not too bad, but if you can see or feel it with a fingernail then it is.

But I think the problem is just rear wheel alignment.

Especially if the bike has been crashed at some time in its life, but often brand new from factory,('specially 70/80s bikes) the lines on the s/w are off.

My old CBX did that slow wander weave in towns (but felt ok at 100) & we straight edge checked the wheel (we had to move it so the adjuster was ½ a position different between the left & right!) & the problem went right away.

[vifferman]

Yeah, sounds like overly tight head bearings to me.

Sometimes a tyre with a wonky tread / too low pressure will cause this, but not usually.

[Paul in NZ]

All the above... And possibly (as well as pressures) some bike just don't like some tyres....

It might have a steering damper too, alter the setting?

Is there any oil in the forks?

Usual stuff...

[keza]

frosty check the tyre were if the tyre is wearing uneven it could be the tyre also check tyre pressures the easy things are the easiest then the balance then the back wheel bearings as transters through the frame canshow up at the front but really the back if not check balance then steering head bearings

p s how the 750?

[FROSTY]

well guys I've found the problem. or should i say problems
First off the back wheel is bent -as in it has a 20mm wobble in it.
the rear disk is also bent -Im not sure het if its the wheel or the axle but Ill suss that later.
The sterring head bearings are buggered -super tight masked the bump in the middle.