headshake on deceleration

[Anonymous]

Why is it always me that will have to be different. Haven't noticed any headshake with neither of my 1150's. My 1100 F Honda had this problem, pretty bad, when I first got it, but a new set of good rubber & it hasn't happened since. Good luck

[earlfor]

There were a few reasons. Dink told me he had the best results without any air in the forks and everything Dink has passed on to me about the 1150 has been spot on correct, so I take him at his word. :-)
Also, the 1150 has in the top of each fork leg, a three position fork spring preload adjuster, so there is no need to use PVC spacers to adjust the spring tension, and the 1150 springs are progressive.

Earl

BTW....I do not use any air in my forks.

Earl

So you don't have any air at all in your forks.
So when I get my Progressive fork springs and new forks seals in, I should be able to run with no air?
Have you run air in the past and found a reason to not run it in your forks or what was your reason??

[cbxchris]

Been out tonight playing just to see if I can get it to stop before I changed rubber. No Luck. I have tried different everything front and back,air pressures in tires and got the front end up off the ground to do just a quick check for loose bearings. It shakes like h*ll. Honestly if I turned completely loose of the bars it would throw me off. But just a touch of brake or a slightly tighter grip on the bars completely removes it. Can`t wait for the tires. My dad has a car wheel balancer. I`ve watched many tires on car wheels go through the same thing on slowing down. I just do hope its that simple by changing tires.

[RacingJake]

Hey Chris does your bike still have the anti-dive system on the front forks, maybe that is causing the problem. I removed all that stuff from my bike sence it does'nt work any how. We have a bump at the finishline and my bike catches some air at 103 mph with no shake, go figure??.

I'm still thinking it's a tire issue

[Dink]

Chris, the headshake is a characteristic of 16" equiped motorcycles!
Jake 1150's dont have antidive!!! they have a variable damping setup, which is almost nearly like an antidive.
Yes the 1150 was banned from re-sale for a short period in Western Australia in 1985, yes it was because of the headshake.
The headshake almost allways occurs at approx50mph on a closed throttle, when the handlebars are gripped lightly.
It is possible to reduce it , but it is difficult to eliminate. Matched tyres are important! as is the freshness of the tyres as these bikes do not like worn tyres!!! Makes certain that the engine has been relaxed in the frame! this is done by loosening all the engine mounts and allowing the motor to settle, then retighten all the engine mount bolts to the correct torque specs, it is very important that you use a torque wrench near enough is not good enough, in fact this applies to every bolt on the bike that has a torque spec, even triple clamp clamp bolts, be certain that the steering head and swingarm pivots are correctly lubed and adjusted ( to torque specs) check tyre pressures every couple of days as a few pounds of pressure cna make a big difference.
A lot of people are amazed that they have never experienced this much rumoured (even legendary) headshake, and indeed it seems like engine vibes withthis model each bike is a bit different, the main cause of the headshake is the 16" front wheel it actually frequencies in the frame, the 16" front is capable of very fast steering, so much so that just frame harmonics are enough the set it to weaving.
BTW Australian delivery 1150's came ex-factory with an 18" rear wheel and no air adjustment on the forks, I personally hate air equipped forks, and hence have never added air to any motorcycle I have owned, I prefer to set it up correctly to start with rather than try and "band-aid" it .
Dink

[cbxchris]

Dink I noticed you had said earlier that he battlax 45`s were a good tire. Thats what I have coming. Did they eliminate most of the headshake in yours? I`ll go back over the engine bolts soon. I really want to try just the tires first to see if that alone fixes it. I just want to know what stops the headshake instead of throwing a lot of things at it then its gone and not knowing what did actually repair it. I know some of the later model honda sport bikes used a 16 inch front. Wonder if they had headshake problems? You describe EXACTLY what mine does. Starts at 50mph and will go crazy unless I tap the front brakes or grip the bars tighter. If I do ride with a firmer grip it doesn`t do it at all. I once had a 78 GS1000 in 78 go into a high speed wobble.(drag racing on the street :roll: ) I didn`t fall but had to stop and clean my pants out. I`ve never forgot that feeling. This is the first bike in 25 years I have had do this. Unnerving to say the least. 8O

[cbxchris]

Dink forgot to ask what air pressure do you recommend on the 45`s? Thanks again!

[oldschoolGS]

Honda CBR900RR had a 16in front but also came with a steering damper from the factory. Good Luck, Ed.

[cbxchris]

Guess i got to ask this....anyone put a steering stabilizer on a 1150? A ES model?

[Dink]

Dink forgot to ask what air pressure do you recommend on the 45`s? Thanks again!

I run 38 front 42 rear,but I do a Lot of high speed highway running, so you may wish to try 36/40 first.
Dink
BTW why would you want to put a damper on, try not releasing the bars as you slow down.

[cbxchris]

If it still shakes when I get done I will probably fit a damper. It bugs the crap out of me I guess. I used a 1150 based kosman top gas chassis once. That bike was quick and it never shook. Of course it was raked with a kosman front end and 18 inch drag tire. Thanks again for all the replys.