Front end wobble when take hands off..?

[ozigoo]

I sometimes take my hands off the handlebars comming down a hill slowing down, and with my other bike never had any problems. Today I did it with the Honda for the first time and the handlebars started to wobble side to side after a few seconds, so I quickly grabed the bars again...This doesnt seem normal, any ideas...the tyres are pretty new, no uneven wear..maybe headstem bearings? Strange as the bikes only done about 20,000km...

[zirconxi_imp]

Did you drop the bike before? Or had a top box installed at the back?? If bike drop before, check for triple clamp and forks alignment, if installed a top box at the back, try setting the rear pre-load to harder setting...

[ozigoo]

Did you drop the bike before? Or had a top box installed at the back?? If bike drop before, check for triple clamp and forks alignment, if installed a top box at the back, try setting the rear pre-load to harder setting...

Thanks Zircon, no topbox but will do the fork alignment and wheel alignment...

[jtopiso_imp]

What are your preload settings front and rear? They should be balanced.
Are your tyre pressures ok?

[the Ferret]

Actually it's a pretty common phenomenon and happens to every model of every brand of bike. Hit the link below and see how many forums they talk about it. Every forum I have been on.

[url=https://www.google.com/search?q=Handle+bar+wobble+at+40+mph+while+decelerating&rlz=1C1CHBF_enUS736US736&oq=Handle+bar+wobble+at+40+mph+while+decelerating&aqs=chrome..69i57.12447j0j8&sourceid=chrome&ie=UTF-8]https://www.google.com/search?q=Handle+b...e&ie=UTF-8

Various theories on why it happens. Some people swear it's tires, or tire pressures, or wheel alignment , or wheel weights or head bearings, or front end alignment, or weight added to the rear of the bike, or luggage rack added to the rear of the bike. No one can say for sure.

I worked in the industry from 1972 to 1989 and people complained about it then. Here 50 years later people are still complaining about it.

When we would contact the manufacturers, they would say "Don't let go of the handlebars"

[Gone in 60]

Every bike I've ever owned does it, even a BMW with the fancy Paralever suspension and steering damper. My Bonneville just had the whole front end replaced and aligned and it does it.

[Charlie Bravo_imp]

I've experienced this too, on several different bikes. Have you ever watched any motorcycle road racing on TV? After the last lap, those guys raise their arms in the air and do fist pumps, high fives, shake their fists in the air, all kinds of celebrating, and the bike tracks as straight as an arrow, but no one can answer why. I had argument with a guy once who said shaking and shimmying never happens on a normal straight bike.

[jtopiso_imp]

Here, Mr Foale explains how wobble is generated.

https://motochassis.com/Articles/Steer/STEER.htm

https://motochassis.com/articles/experim...-geometry/

(old stuff, but... probably right)

I wonder if wheel stiffness will also be a factor -I guess it is-, and if there is any significant difference between spokes or cast wheels.

My opinion regarding racing bikes not showing the issue: they are set-up perfectly in terms of damping for that rider, that tyre stiffnes/pressure, the whole bike is much stiffer than most road bikes (forks, frame, wheel), and caster angle and longitudinal trail are pretty small, so there is a short moment arm comming from the contact patch, so small "steering forces" are generated from the tyre, and they are overcome by stability that inertia provides.

[pekingduck]

Many years ago I saw an older CB750K on the freeway "ridden" by a guy standing on the seat, just surfing along past traffic at 70 mph. Didn't appear to have any wobble.

[Houtman_imp]

Many years ago I saw an older CB750K on the freeway "ridden" by a guy standing on the seat, just surfing along past traffic at 70 mph. Didn't appear to have any wobble.

I wonder how old he was when he died ….