motorway riding for a newbie

tpp · Borekit Bruiser Joined: 27 Dec 2005 Karma :

I bought a kawasaki Z 750 two weeks ago.
been on the the bike about 12 times, mainly in town and the odd dual carriageway ( speed around 65,70 mph)
took the bike on the M40 between wycombe and denham
got up to 70 and the bike felt it was snaking or moving from side to side a couple of inches,
my mate says the rear tyre is really square and could cause this
the tyre is Bridgestone bt012
can anyone explain it to me,or i am just panicking because i am not used to motorway riding ( it was touching cloth material) by the way i am 42 and drive a car and passed my das

Bendy · Mrs Sensible Joined: 10 Jun 2002 Karma :

You got a flyscreen or anything non-original on it?

R4nger · World Chat Champion Joined: 05 Jan 2005 Karma :

This should be in the newbie section Razz

bish777 · World Chat Champion Joined: 11 Nov 2004 Karma :

bikes can follow the ruts in the road left by lorries-try the middle lane or stick to the centre of the left lane.

Lighter bikes suffer worse. My FJ1200 barely noticed them, but my GSXR is badly affected by ruts.
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tpp · Borekit Bruiser Joined: 27 Dec 2005 Karma :

Normal screen that comes with the bike, although i have just bought a vario screen

Rookie · World Chat Champion Joined: 09 Feb 2005 Karma :

Is this not just aquaplaning? What was the weather like?

tpp · Borekit Bruiser Joined: 27 Dec 2005 Karma :

Weather was dry ,the road appeared dry
there was no wind,except from a*se

nrml76 · Brolly Dolly Joined: 05 Nov 2005 Karma :

Was this mainly when decelerating using engine braking? If so it could be due the torque. Use the brakes to slow down instead and it should disappear. This is not so much of a problem on smaller bikes such as those used for DAS training. You notice it when you hop onto a big bike directly from DAS.

kwacky · Nitrous Nuisance Joined: 28 Dec 2005 Karma :

a BT012 is a very soft compound. It'll square off quickly.

Rookie · World Chat Champion Joined: 09 Feb 2005 Karma :

Yeah if it was dry I'd check out your tyre, and your tyre pressure.

tpp · Borekit Bruiser Joined: 27 Dec 2005 Karma :

Would a square tyre cause this
the tread is thin in the centre and has a few wear bumps

Mongrel · Scooby Slapper Joined: 29 Sep 2005 Karma :

A badly squared tyre may cause this....by I'd be more inclined to look at tyre pressure personally.

Did it worsen with speed or weight shift?

As has already been pointed out you can 'track' in the ruts you can get along the inside lane caused by lorry tyres repeatedly compressing the same bit of tarmac.

tpp · Borekit Bruiser Joined: 27 Dec 2005 Karma :

kwacky · Nitrous Nuisance Joined: 28 Dec 2005 Karma :

sounds like you need to change your rear tyre

xploitation · Nitrous Nuisance Joined: 29 Sep 2005 Karma :

[quote="bish777"]bikes can follow the ruts in the roadquote]

i know what you mean!!! was going alone to day when my bike drifted to the right! looked down and my wheels were in the grove between the new and old tarmac!! give me a fright!! Laughing

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stinkwheel · Bovine Proctologist Joined: 12 Jul 2004 Karma :

A lot of the GPZ/GPX series kawasakis were known for getting a bit twitchy feeling on a worn (<2mm) front tyre too. Don't know if yours is the same.

Shouldn't be getting a speed wobble at that sort of speed in any case. Check tyre pressures and tread depths. Also might be worth checking wheel alignment, and seeing if the steering head and wheel bearings have any play in them.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

stinkwheel · Bovine Proctologist Joined: 12 Jul 2004 Karma :

Something else that you might not be aware of since you did direct access is that some heavy vehicles trail a mass of 'dirty air' behind them. I find box vans, skip lorries and tankers are the worst. If you get into the vortex of air coming off the back of them, the bike can land up being all over the place.

You never learn about this properly until you have had to ride about on a 125 for a long time, using the slipstream of the wagons to give you a 'tow' up to the heady heights of 68mph. Wink

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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

Finglonga · World Chat Champion Joined: 27 Jul 2004 Karma :

Tankslapper Alert Shocked

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greenmeanie · Trackday Trickster Joined: 29 Dec 2004 Karma :

try stiffening the rear shock. if it is too soft it will cause the bike to move about especially noticable at speed. Thumbs Up

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Barney · Spanner Monkey Joined: 17 Jun 2005 Karma :

Shaun · Likes 'em bent Joined: 17 May 2003 Karma :

If you aren't doing 120mph by the end of the slip road you're a pussy.

Wave2k · G's Stalker Joined: 06 Apr 2004 Karma :

tpp · Borekit Bruiser Joined: 27 Dec 2005 Karma :

Shaun · Likes 'em bent Joined: 17 May 2003 Karma :

Jeeze lighten up it's a joke, although I do try it every time anyway. Wink

Irezumi aka Reuben · Carrot Top Joined: 28 Sep 2004 Karma :

Although you said there was no wind something to watch out for, connected to stinkwheel's large vehcile scenario is gust's of wind catching your hand/hand's. A large gust will catch you unaware and push your hand back, something to be wary of.
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