Wobbly bike

[Grinch]

My wifes M600 tend to wobble a bit when at speed of 70+mph and sometimes when braking or rolling off the throttle. The bike had been lowered to the max to allow her to ride it. I'm just trying to get some ideas as to how I could smooth the ride out a bit more, I don't think the head bearings are stuffed.

[rxtim]

Start with tyre pressure before anything else. Once you have eliminated that, move on to suspension. As long as the bike was lowered evenly that in itself shouldn't cause a problem.

A 600 monster is going to wobble a bit at above 70 anyway, the difference between the monster and a faired bike is huge. I can sit at 190+ on my Busa on an RAF runway and feel no wobble, all quiet. Above 70 on the Monster is hard work, well in a straight line anway!

[Fosse Foxfight]

My wifes M600 tend to wobble a bit when at speed of 70+mph and sometimes when braking or rolling off the throttle. The bike had been lowered to the max to allow her to ride it. I'm just trying to get some ideas as to how I could smooth the ride out a bit more, I don't think the head bearings are stuffed.
Sounds almost certainly like summat at the fron if braking (both brakes and engine) are bringing it on. When you say lowered to the max, what do you mean?

Sean

[DesmoDog]

Since I changed to the clip ons I'm getting a little shake at brake. Hadn't thought about any of the above rather than it being the new set up. Now I'm worried. RAF runway eh?

[rxtim]

RAF runway eh?
Yep, 190 thru timing lights showing about 215 on the clocks for those like to think they show how fast you are going! Speaking of which, the speedo on my 916 is amusing!

[norrie]

I would try raising the bike very slightly at the front.
It sounds as though the rear is higher than the front which makes the bike unsteady.



Norrie.

[slob]

Yep, 190 thru timing lights showing about 215 on the clocks for those like to think they show how fast you are going! Speaking of which, the speedo on my 916 is amusing!

I've compared my speedo to a Garmin GPS on the bars and reckon my '02 620ie only reads about 4% fast, at SLIGHTLY lower speeds obviously.
As rxtim says, start with tyres(pressures/wear/are they matched?) then move on to suspension.
I find 1/2 turn on the rear spring makes a huge difference to stability at motorway speeds even though the effect is felt at the front.

[Grinch]

I'll have a look at rasing the forks a tad. When I mean lowered to the max, I mean forks dropped though the yokes, and all the suspension set as far down as it will go.

[Mrs Soup]

The bike had been lowered to the max to allow her to ride it. I'm just trying to get some ideas as to how I could smooth the ride out a bit more, I don't think the head bearings are stuffed.

Does the bike shakes its head on fast bends and generally under a feathered throttle ?

I have been through this myself, if you have done as I did and wound off all the pre-load on the shock to lower the ride height, that's the trouble.

Cure - shorten the suspension U bracket to allow some pre-load back on the shock, or change your riding style so you take fast sweepers on an opening throttle to put some load back on the rear end.

Hope this helps

[Phoenix]

A 600 monster is going to wobble a bit at above 70 anyway, !

Nope it shouldn't - mine doesnt! - it has done in the past but it's certainly not something thats acceptable. Mine eventually turned out to be weak fork springs and incorrect weight oil.

After the tyre pressures as stated then don't forget to check the rear suspension - front end stuff can often be attributed to the rear.
As stated - check the rear ride height too.

[M600TED]

I'll have a look at rasing the forks a tad. When I mean lowered to the max, I mean forks dropped though the yokes, and all the suspension set as far down as it will go.
My forks are showing 5 rings and i get the same simptoms? so would this be half my trouble? sorry for the hijack :o

[Jason]

Have you checked the steering head bearings for wear? This can give the symptoms you describe.

[Mrs Soup]

I'll have a look at rasing the forks a tad. When I mean lowered to the max, I mean forks dropped though the yokes, and all the suspension set as far down as it will go.

Grinch - This is how mine was set up before it was lowered. Leave the forks where they are and put a couple of clicks on the shock. Should sort it out, it did for me. :D