The Wrong Kind of Rolling.

[Vince]

I has a very unpleasant handling fault startup recently, It was a general looseness and a weave-like I have a flat tyre or a blustery headwind. It started right after a new rear tyre was fitted. I couldn't detect any knock slop or movement. A couple of months back I had gone through the rear spokes with my Spoke Torque wrench and only 2 needed a slight nip to 4.5n or whatever the figure is and a slight nip on the steering head, both are tapered bearings. After doing this the bike went very well, nice and stable but it didn't last long as this looseness developed on the really bumpy last ride and was distinctly horrible heading home on the expressway. So off to Western Central Laverda Headcouters for a better set of hands than my cakness. The main issue was a leaking left fuel tap and that got sorted. 3 new plugs went in and the carbs were balanced and the Ignition got a fiddle and now the bike sounds like a dream. The next check was wheel alignment with a very special tramel and the rear wheel was out of aliment, maybe 2mm. That was sorted but hardly a smoking gun. Next, the steering head adjustment was checked and one definite smoking gun was found. It was substantially TIGHT. Either I had nipped it up too much or it had self tightened. Once eased off that rolling disappeared. I am a happy camper as I wasn't looking forward to the 4-day Snowy Ride but now I am really keen to go. BTW sorry I missed you, Tom, we passed mid-Blacktown. Don't you just love self-inflicted fuckups.

 

[Legs]

One of symptoms of over-tight steering head bearings can be a weave at around sixty kph, it takes a bit for the steering to overcome the stiction/friction and self-centre.

 

[Vince]

It wasn't pleasant on the expressway at 100ks

 

[piranha-bro2]

The usual cause is that the adjustment is made and deemed right THEN the top nut is tightened down to lock it - this compresses the threads and the result is eq to about 1/4 of adjustment on the tight side. Not saying yours was such, Vince, but it is very common. A lot of bikes use the double notched threaded rings under the top clamp, so then the top nut above the top clamp has no tightening effect.

Any time you feel that vague weave, correct, correct, correct imperceptibly trying to make the bike go straight, it's invariably either overtight or worn and notchy steering head bearings

 

[Ventodue]

The usual cause is that the adjustment is made and deemed right THEN the top nut is tightened down to lock it <snip>

Yup, contemporary Honda-Wondas used a double nut set up (as did Suzukis, I believe) AND a lock washer as well

But not Marzocchi or Ceriani.