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Bad head shake

After installing Hannigan Astro 2+2 on a Triumph rocket and after a great many adjustments, and many road tests, some at high speed , I took off on my first worry free ride. Three miles down the road the worst high speed wobble,done at low speed [25mph] it was very violent. After inspection nothing broke, all attachments .tight and did not move. all attachments are factory except a couple I grew in size for added strength. any thoughts of what might have happened would be appreciated. Thanks in advance ,seabum

Do you use a steering damper? Some bikes with excessive trail need them.

Lonnie

Not saying this is the case with your rig however we have seen where Hannigan hangs their lower mounts with all thread having to take lateral loads flex and as such either need to be redone better thought out which some of which you already figured out for your self other wise you will have to hide the shake with a steering damper. In general if your steering head bearings are not loose, tires are in good condition, the mounts do not flex you usually can get most if not all of a head shake to go way by adjusting your toe in slightly. BTW, we do make triple tree's to lower the steering effort on the Rocket and you can run an automotive tire on the stock rear wheel.
Jay G
DMC sidecars
http://www.dmcsidecars.com
866-638-1793

Jay G DMC sidecars www.dmcsidecars.com 15616 Carbonado South Prairie RD Buckley WA 98321 866-638-1793 Hours Monday - Thursday 6-4:30

many thanks for advice, I don't understand why it was working so smooth, then all of a sudden all hell breaks loose. all fittings tight ,nothing moved . Will take advise and start over with adustments.

Seabum,
That is just part of life in a rig.
They all tend to go to head shake at low speeds due to physical forces fighting each other, (some more, some less, depends on adjustments, loads and geometry if it happens at lower or higher speed typically somewhere between 15 and 30kmh = 10 to 20mph)...specially when you go downhill over road bumps. ...Go faster or go slower, but GET OUT OF THE SHAKING SPEED FAST AND DO NOt ATTEMPT TO PLAY HERO BY TAKING OFF YOUR HANDS IN THAT MOMENT: GRIP HER HARD AND PULL THE THROTTLE or let it off.
Once above that speed your baby becomes a sweety again. and below too.

I remember one occasion when the tiny 350 Jawa hit my right wrist so hard it ached for half a week.

Once upon the time I started to push rigs without any theoretical base...I got the German manual fast after my first ride home. 3 times into the pasture on 145km 90miles and next day a road side plock got shortened by my sidecars front fist and my knee...
Read, understand and practice the advices from the manuals in the link section:
http://sidecar.com/links3.asp
We have many people here who would like to teach at least the basics, perhaps someone is close to you so you can learn under guide. Later participate in a STEP course.
Good luck and wellcome in the club of the uncurable rig virus.
Sven

PS: By the way on none of my 3 rig I ever passed mach speed and got into high speed wobble. The occasion I had to jump off my Solo Norton Commando the wobble was due to multiple problems and over load, but not high speed.

Was the car loaded differently when the head shake occurred?

Once again many thanks for help and advise. Had fork oil changed to heavier mix, damper added and more air added to tires. Will try again. Car was unloaded at all times.