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Offline artist

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Slight Head Wobble and Jitter
« on: May 23, 2018, 10:40:03 AM »
Hi Folks,

Please excuse me if I'm raking over old grounds here but I note similar issues with a jittery front end and head wobble. I see some posters are correct about loosening off on the handle grip as this does help but as I'm trying to hang on for dear life it seems understandable to hold on  :005: My issue comes in circa 95-105 in a straight or 80-90 if hitting the throttle and swinging out to overtake. I can virtually sort the straight line by slacking off on the grip but not when swinging the bike and giving it some welly.

I also notice Dynamic mode and a firm suspension mode helps so my thoughts are to go with an aftermarket damper like Hyperpro or Ohlins. I'll also go through the suspension setup guide in the manual to see if I can get it as close as possible for my weight but will have to get something sorted fast as I don't like the front end flying away whilst cranked over at 90mph

I've also got a track day booked at the end of the month so any pointers will be greatly appreciated
As sure as God made little green apples and bears $hit in woods

Offline SimonS1KR

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Re: Slight Head Wobble and Jitter
« Reply #1 on: May 23, 2018, 02:01:20 PM »
Assuming all the obvious stuff is OK (preload set up for your weight, tyres in good nick and inflated correctly, bearings not worn etc) and that youre gripping with your knees to keep the weight off the bars, the next step would be to consider an aftermarket steering damper.
« Last Edit: May 23, 2018, 02:02:01 PM by SimonS1KR »

Offline Simonr23

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Re: Slight Head Wobble and Jitter
« Reply #2 on: May 23, 2018, 10:46:41 PM »
How/what youre describing, sounds normal to me. This bike isnt an on rails bike under medium-hard throttle. It shakes its head and likes to buck about a bit as the rear tyre gets loaded up under diagonal(as in corner exit and pulling out to overtake) and rear-biased loads(just giving it 80-100% throttle in a straight line). It feels disconcerting at first, but if you can get confidence in the fact its normal, it becomes fun :)

At my last track day, I noticed it was heavily surface dependant(straight line head shake) as on the billiard table smooth tarmac there, it was basically non-existent. But when back on the back roads, it was very frequent(camber, bumps, surface changes)

Offline windyrun

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Re: Slight Head Wobble and Jitter
« Reply #3 on: May 24, 2018, 01:53:00 AM »
Multiple threads and posters recommending steering damper led me to install one even though I havent noticed the issue. May not ride as hard as others (have been into 3 digits on private roads of course), but adjustable damper does let one dial things in to how you prefer.

This bike has taught me to properly grip tank with knees though
and leaning forward in prep for hard accel has kept me on board as well :)
« Last Edit: May 24, 2018, 01:56:48 AM by windyrun »

Offline artist

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Re: Slight Head Wobble and Jitter
« Reply #4 on: May 24, 2018, 12:18:08 PM »
Thanks Guys. Interesting to hear you state this is "sort" of normal for the S1000R and I'll try gripping with the knees although surely fine in a straight line but on the bend I like to get the knee away and down and shift the weight slightly. I haven't set the preload yet so at circa 96Kg I'm going to go two clicks tighter on the rear and one on the front and then test. I'm also going to Race Lab in Bournemouth shortly to get a more accurate assessment and settings. I just don't like that loose head end so I'm sorting the "S 1000 R 14-18 - Hyperpro complete Damper Kit - RSC"  from OZ. I'm sure once I get the balance and damping right I'll feel more confident on the leans and letting rip with the throttle

I'll update you if I find the right settings or what best suited my needs

Regards
As sure as God made little green apples and bears $hit in woods

Offline artist

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Re: Slight Head Wobble and Jitter
« Reply #5 on: June 11, 2018, 11:04:05 AM »
UPDATE:

It turns out I was riding without any pre-load at all ....sweet, no wonder she's floating around like a ballerina with Porky the Pig on her back  :745:

* So I turned my rear mono pre-load all the way in and wound it back four turns. This now sits with the recommended sag!
* Front pre-load I wound in about half way. If you count the lines on the yolk bolt it has about six lines showing without any pre-load so I wound that it till it showed three. The sag on this is still a bit high but I didn't want to load it all the way in on the front as the rebound didn't feel too good any tighter.

The above removed the jitter and head wobble but I still felt the front end a little too responsive at times so I'm hoping the damper will do the rest.

....AND the Hyperpro RSC just arrived from OZ so I'll be on that this evening. Thank you Walter Preisig from YSS SuspensionShop.
As sure as God made little green apples and bears $hit in woods

Offline artist

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Re: Slight Head Wobble and Jitter
« Reply #6 on: June 12, 2018, 01:09:53 PM »
I fitted the Hyperpro RSC damper last night and apart from a slight problem with the box screw supplied being too short, all went well and took no more than 20mins. A quick trip to ML UK Ltd of Portsmouth this morning and the nice chap on the counter even opened the door to me at 7:30am and sorted me with a longer box screw, which i promptly fitted and I was soon out on the M27.

What can I say ....5 clicks in on the damper and she's as smooth as anything. Much more planted and steady through the bends and head rattle/jitter is completely gone.

« Last Edit: June 12, 2018, 01:11:54 PM by artist »
As sure as God made little green apples and bears $hit in woods

Offline windyrun

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Re: Slight Head Wobble and Jitter
« Reply #7 on: June 12, 2018, 01:34:10 PM »
Glad to hear your happy with the hyper pro. How many clicks total are available for adjustment? Just curious where in the spectrum 5 clicks in is.

Offline artist

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Re: Slight Head Wobble and Jitter
« Reply #8 on: June 12, 2018, 03:36:36 PM »
Hi Windy ... I'll check the max number of clicks to full load for you shortly and post the info back here. TBH I thought I'd read a few posts that said circa 20 clicks was full on and someone definitely mentioned five clicks was about right. I guess where I want to be for the road is just enough to damp the rough an uneven surfaces but not too much as to counter a quick response. Likewise when heavy on the throttle it needs to damp to keep things stable. Given that my Hyperpro is the RSC model maybe i should be able to push to a click or two higher than the CSC. Hot sure but I'll find the optimum shortly
As sure as God made little green apples and bears $hit in woods

Offline windyrun

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Re: Slight Head Wobble and Jitter
« Reply #9 on: June 12, 2018, 09:13:17 PM »
Thanks for the update. I think I remember the 20 clicks also so have an idea how much adjustment you're using so no need to mess about with your adjustment for me. but thank you regardless.

 


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