Cornering Question

[FastJohnny]

I am a new rider, I just started this year, and have logged about 2000 miles. I bought my bike used from a guy in NH who had put about 6000 miles on it.

Anyways, I've been pushing myself to lean further and further over, and have shrank the 2" chicken strips that were on my tires down to about 1/2". I was going around this curve yesterday, and came in hotter than I would have liked:



I was going about 40 mph, and this is the kind of corner you would take at 15-20 mph comfortably in a car. So I approach the corner, start leaning, realize its not enough, lean more, and more, and more, until I am pretty uncomfortable and just praying for it to end when my bars start to shake from left to right. This scared the piss out of me and all I wanted to do was roll off the throttle, but I didnt. I pulled out of the corner with my heart pounding and a massive adrenaline rush.

What made my bars shake like that? Is that what bumps in the road feel like when you are leaned over that far?

[neuthunder]

last time i had a shake like that in my handlebars, it was when I truck suddenly stopped in front of me and I had to brake real hard.... next thing I know I'm on my the ground in the middle of traffic on 93 so when that question is answered It might shed some light onto mine.

[richw]

God

You have had your warning !


I have never heard an adequate explanation. Glad to see you did the right thing. Lean Lean LEan

[neek]

that will happen with some bikes, going hard thru a turn. this is where a steering damper will help...

[FastJohnny]

Originally posted by neek
that will happen with some bikes, going hard thru a turn. this is where a steering damper will help...

My bike has a steering damper. Is this because of too much weight on the front end? I catch myself getting lazy and putting too much weight on my wrists, could this have caused it?

[NinjaSwan]

sounds like you got lucky! Is that pic the turn you're talking about?

[Tabby]

I don't have a good answer for you. Don't know you, the bike, or the road. It could have been ripples in the pavement. Anyhow, you ought to consider some schooling. I don't know if you have had any, but if you have, consider more. Trying to find limits on the street is very risky. Take it to the track. I'm sure others here will chime in soon.

[Ken C]

First, SLOW DOWN!. Scairn yourself will set you back, not progress your effort. Stretch your comfort level slowly.

Second, pushing hard on the street with unpredictable surface conditions is a recipe for disaster.

What caused your handlebarsto shake is likely your tension from panic. Good for you for resisting nature and staying on the throttle and keeping your lean. Most riders chop the throttle and lose the front or if they don't slide, will stand the bike up and go off the road leaving a big skid mark from their rear tire (bad braking technique).

At full lean on a road with even a little dirt or broken pavement, traction is at its limit. Even a twitch of movement at the bars will cause the frnt tire to squirm or skip.

The best place to push your limits is at a track day. You're ready.

tonystrackdays.com

[Honclfibr]

My vote would be too much mid corner correction combined with a death grip on the bars. You're upsetting the bike's suspension making significant steering inputs, then fighting it as it tries to correct.

I know when I first started track riding I had too much weight on the bars, and any mid corner changeswould cause the bike to do bad things. I thought it was the limits of my motorcycle, turns out it was the limits of my riding.

Relax, let the bike do it's thing, and work on gradually increasing lean angle and speed through corners you know while letting yourself get comfortable with how the bike feels. Of course, the best place to do this is on the track

Edit: or listen to Ken C, who is clearly both a better motorcyclist and a faster typist than I

[legalspeed]

Check your damper.

No, it is not the way it is supposed to work.

I don't think you had head shake, I would have your fork oil changed, air bubbles, spring rate, etc.

Take it to the track if you want to push it. Your physical and legal well-being will thank you.

Peter Kates at GMD Computrack is a good resource, one you can trust. If you take your forks off, shipping is not that expensive.
See his banner in the suspension section.

-D

[FastJohnny]

Wow, thanks alot for the very technical explanations guys! Way more than I was expecting. I want to get into track days, but they're going to have to wait until next year. For the mean time I'll just slow myself down, and try to be smoother.

[benVFR]

For the experience/racer/technical people..

What is the actual cause of this? Would not enough throttle do this? Or is it likely just the death grip on the bars? I had always assumed the only time you'd get oscillations which test the steering damper was when you were very hard on the gas and the front was getting unweighted.. which sounds like it was clearly not the case here.

I have really never had this happen, I've slid the front and rear, etc.. but I've never really had a death grip since I had already been through all this on my mountain bike.

The only times I've ever had anything like this happen were with my SV650, which had never had the suspension set up properly.. if I hit a series of bumps/ripples at maximum lean the front end would definitely get up set but the bars still didn't really wiggle. I could also get this effect when I grounded parts out but again it didn't really feel like the bars shook.

The VFR suspension is not exactly world class but it has been good enough I've never really had the same symptoms I got with the SV.. I've pretty much touched everything down (at the track) that I can without crashing and that and/or the bumps never make the suspension get really upset. (The extra 4 years experience can't hurt either of course)

[richw]

My ancient kawi used to oscillate in turns until I stiffened and gusseted the frame.

I have also heard of tire breking and regaining traction.


I have seen pitures of racers usually TT's head shake then explode of the bike in a flying W

Obviously to check all the usual suspects in head and swingarm

Surpisingly if the head bearings are too tight you can set up poggoing which leaned over may be this


Best advise is back off a tad and don't do that no more.

[Ken C]

Not that a discussion about steering dampers, traction, etc. isn't good, but focusing on the bike is more than likely barking up the wrong tree and is probably not helpful. Unless there is something really wrong with the bike (doubful) then the place to look is the rider.

A new rider enters a corner faster than he's comfortable= problems.

When it sounds like a zebra, looks like a zebra and smells like a zebra, it's probably a zebra.

[rjh200]

Is that rt2 ?

[JeffL]

Originally posted by rjh200
Is that rt2 ?

Doesnt look like anything on Rt. 2. Not the western side of 91 anyways.

Definitely relax yourself on those bars.

[Awesome]

Don't hold so tight, get off the bike and start the turn from the outside taking it wide.

[TTD]

My vote is DEATH GRIP at the bars not allowing the front wheel to do it's thing.

As Ken said... blaming the bike at this point is not going to do anyone any good.

If you can reproduce the shake regularly ... when you're NOT crapping your pants... then we'll talk bike mods.

[FastJohnny]

Thanks for all the input guys.. I really don't think it's the bike either, Im pretty sure its something I did wrong. Im thinking it was some type of combination of too much weight on the bars, not enough throttle (it was steady) and maybe some wavy road.

Yes, that was the curve.
No it's not Rt. 2.

It's called Porter Lake Rd, its the last street on the right on Dickinson Street in Springfield, and runs onto Converse St. In Longmeadow. I used to live in the apartments that are at the beginning of it, and no one uses it but the people who live on it. It's a really twisty minute of fun.

[TTD]

That's funny.

I used to do Porter Lake Road all the time.

I was such a squid.

[legalspeed]

Originally posted by richw
poggoing

air bubbles in a do it yourself fork oil change. or from another source