GSX1400 Owners .org

General => Bike Chat => Topic started by: KiwiCol on Sunday, 12 February 2023, 01:43 PM

Title: Speed wobble
Post by: KiwiCol on Sunday, 12 February 2023, 01:43 PM
I took the bike out fir a bit of a run this afternoon,  95% sedate, but there are some nice, unemcumbered straights in our local environ, so let her rip for a bit on one of them. Around 200 she got a wobble on, not a tank slapper wobble the whole bike was going.
Gently throttled off n it stopped around 140ish.

Was wondering if wind turbulence could cause this at that rate of knots?  I had a loose top on n it was blowing / flapping about at the time, so guess it was that, but just asking if anyone else experienced similar.

Oh, it was a private road I was on at the time . . .  Yeah right.
Title: Re: Speed wobble
Post by: Kiwifruit on Sunday, 12 February 2023, 02:07 PM
When I was down your way last I complained of same to a mate who sent me to the guy that rides his race bike. First checked wheel alignment, was bang on then he said front could be too soft. Stiffened up front end preload. Problem solved.
(I had panniers, topbox, tent and tankbag so we most likely weighed about the same)
:hat:
Title: Re: Speed wobble
Post by: VladTepes on Sunday, 12 February 2023, 03:35 PM
Yes my experience is that my GSX goes 200 (2 up with luggage) on similar 'closed roads' ;)
Title: Re: Speed wobble
Post by: KiwiCol on Sunday, 12 February 2023, 04:19 PM
Cheers Col, I'll give that a go.

I see you're getting a bit of wind & drizzle up your way . . Hope the homestead stays safe.
Title: Re: Speed wobble
Post by: GSXKING on Sunday, 12 February 2023, 04:22 PM
I've never suffered a wobble at Highspeeds & most of that was at trackdays 😈😈
Tyres grow taller when they're spinning that fast so pressure is critical 👍👍
Title: Re: Speed wobble
Post by: Kiwifruit on Sunday, 12 February 2023, 05:33 PM
Quote from: VladTepes on Sunday, 12 February  2023, 03:35 PM
Yes my experience is that my GSX goes 200 (2 up with luggage) on similar 'closed roads' ;)


My rear mounted cruise controller starts going apoplectic over 130kph. No such problems from the tent, topbox or panniers though.
Trying to pick the right time to mention my latest speedo margin of error. Am sure the speedo read 100 when for a fee of a mere $80 it was confirmed to read 115kph.  :facepalm: not again.

All good so far thanks Col. Have been securing anything that might take flight without permission.
Title: Re: Speed wobble
Post by: grog on Sunday, 12 February 2023, 06:05 PM
First sign of a speed wobble and would be sold. Mines solid as a rock, been to 240 closed road, ok. My old Kawa 900 got sold real quick, 3 of us had them, all scary. We spent hours trying to fix, there was no fix.
Title: Re: Speed wobble
Post by: SwiftandBold on Monday, 13 February 2023, 03:05 AM
This happened to me and it was a tyre pressure issue- easy check

Title: Re: Speed wobble
Post by: Almost on Monday, 13 February 2023, 04:07 AM
Unbalanced  wheels?
Title: Re: Speed wobble
Post by: KiwiCol on Monday, 13 February 2023, 05:13 AM
Thx guys, there's a few things I'll be investigating, the front pre-load, the tyre pressures (which were fine that day, but dunno about for those speeds) and just keep the speed down to subsonic levels.   Thinking about it today, I remember there's an issue that needs attn on one of the fork legs, so that def won't of helped.

Wheels are balanced & I have my own wheel balance rig & weights, so all good there.
Title: Re: Speed wobble
Post by: Hooli on Monday, 13 February 2023, 06:54 PM
Fork bushes? a bit of wear there makes the front a lot less stable.
Title: Re: Speed wobble
Post by: KiwiCol on Tuesday, 14 February 2023, 04:46 AM
Quote from: Hooli on Monday, 13 February  2023, 06:54 PM
Fork bushes? a bit of wear there makes the front a lot less stable.

No, oil leak.  Will have to get around to putting new seals and fresh oil in.