Shaking while braking...

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Mitch
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Shaking while braking...

Post by Mitch »

i gotta problem. when i brake really hard from 200+kph to 60kph for a hairpin (eg turn 3 at QR) i get a whole heap of shake thru the forks. i am going to pull the brakes apart and redo them (sticking piston?)but should i be looking elsewhere as well?

some people suggest it could be warped discs but how do we check for that? i have wonky eye at the best of times!! others have suggested a p!ss poor suspension setup, any ideas :?:
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re: Shaking while braking...

Post by bonester »

Might be steering head bearings too. :shock:
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re: Shaking while braking...

Post by Barrabob »

sounds like turn 3 at willowbank its just a rough as hell brakeing area aparently the dirt on the side of the track is smoother.

If your disks are warped they will pulse, like grap harder every time the wheel goes around and it means you might need new disks or have them machined and its the only way you will get rid of the pulsing.


sounds like i might be time to do up the front end with a fork oil change and grease and adjust the steering head bearings while you are at it. :D
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re: Shaking while braking...

Post by redzedx7r »

:( sounds like warped disks, you wont see with the naked eye.
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re: Shaking while braking...

Post by Neka79 »

i agree with beryl..warped discs would give tight spots under braking...head stems would cause shake, as would an unbalanced wheel (ussually all the time tho)..check the wheel weight hasnt come offf??..maybe fork seals are dodgy (one only stuffed??)..fork springs?? tyre is stuffed (that can cause it)..def sounds front end..maybe as previously said, front end rebuild to a degree?? over haul it?
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Mitch
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Post by Mitch »

ok then here is an update on my shaking problem.

i went out to the Champions ride day on the 12th (very tall guy with green leathers on orange 6r) and had major problems with it every where as i had changed over my pads and bled the lines.

what was now happening was i lightly brake and all fine.
i get on them a little harder and i get the shakes
i get on them real hard and all is well

i asked Colin at champs and he said that my discs may have a stuck button or i may have a rasied bits on the disc but is nothing to worry about as his new gsxr1000 did the same thing and just to not to pussy aroud with the brakes just jump on them hard!!!
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Post by Jonno »

Ok I will have a stab since Iam no expert forgive me if Iam off track (excuse the pun) but have been reading alot about it recently so lets see.

Check the headstem bearings and brakes as suggested already.
Might be too much compression set for that particular corner or in general, this can only be set properly by adjusting and riding until you are happy with it. Or it could even be too much low speed compression damping if that comes into play, not 100% sure on the best way to adjust that but maybe check that oil height is correct, then decrease compression a bit at a time until chattering and shaking stops.

HTH and I am not sending you up the wrong path.


If you want some good web pages for setting up suspension try these:

http://www.sasbk.co.za/suspension_setup_guidelines.htm

http://home.earthlink.net/~alexcuster/m ... set-up.htm

http://www.gostar-racing.com/club/motor ... set-up.htm

http://www.sportrider.com/tech/suspension/
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Mitch
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Post by Mitch »

well Scotty the headstock bearings are on order. before i go to far in the suspension settings it is prob a good idea to have the both ends "refreshed" as both the forks and shock are prob stuffed (being 10 yr old!)

any body know of a good (but cheap) suspension guru?
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Post by Barrabob »

I used this bloke http://www.allsuspension.com/ and while he isnt the cheapest around he can rebuild your shock and change fork oil.

But being a ten year old bike maybe you could change the fork oil yourself and pull out the shokie and take it somewhere to be rebuilt that would be a way cheaper option.

there is a place at sherwood that does heaps of shokie rebuild work i think its called radchrome or something like that i will try to look it up for you.
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Post by Barrabob »

Here you go give these guys a ring they do fork rechroming and shokie rebuiding and i have heard there prices are quite reasonable, i dont know if they do revalving as well but they are worth a ring for a price.

Rad Hard Chroming

Unit 3014/ 496 Sherwood Rd Sherwood QLD 4075
ph: (07) 3278 5056 Motor Cycles, Parts & Accessories
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Post by Jonno »

Mitch wrote:well Scotty the headstock bearings are on order. before i go to far in the suspension settings it is prob a good idea to have the both ends "refreshed" as both the forks and shock are prob stuffed (being 10 yr old!)
any body know of a good (but cheap) suspension guru?
Good idea, also new or close to new tyres are the best to set up with, as old squared off tyres make it way to hard to get it right.
My $0.20

There is a good mob up here at Beerwah (near Australia Zoo) I will get you their name.
When I went there they were going to strip, re-valve with gold valves, re-oil, re-spring for my weight front and rear suspension for $800 which I thought was a fair price. Since I was fairly happy with my bike and certainly not 800 bucks unhappy with it I never did it.
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Post by NovaCoder »

Yep, might just be the suspension 'bottoming-out', stick a cable tie around the fork-leg and see how much of the travel you're using under hard-braking.


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