Forks

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DJWALKER
Posts: 58
Joined: Mon Sep 14, 2020 6:10 am

Forks

Post by DJWALKER »

Hi anyone feel forks juddering under low speed
Braking obviously using front brake.
Is this a common issue ?
Thanks and enjoy the sun .
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8541Hawk
Posts: 1847
Joined: Sat Jul 21, 2012 4:21 am
Location: Bella Vista, AR

Re: Forks

Post by 8541Hawk »

More information please.......so confused :lol:
They call me "Mr. Flat Earther"
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MacV2
Posts: 15809
Joined: Sun Jan 21, 2007 12:07 pm
Location: Grain

Re: Forks

Post by MacV2 »

It's either loose/worn headrace bearings or worn fork bushes...

First port of call, check to see if you have any movement in the headrace... Get the font end off the ground, from in front of the bike, grasp the fork legs & pull towards you. There shouldn't be any movement. If there is then that'll be the headraces... Remove the top yoke & the top lock nut, has a thin locking washer that you have to bend the tab's down. Top one should be easy to remove. Then you could try to tighten them up by tightening the lower one...However... It's worth removing the bottom nut to reveal the actual bearings... The bottom one either drift it loose or C-spanner if you have one that fits.

If the headrace bearings are ball races then they are probably in there from the factory. Best to re grease anyway & the lower ones, If your going that far you may as well replace with Needle roller bearings.

https://www.ronayers.com/oemparts/a/hon ... ering-stem

That i'll be a fork out job.

If its not the headraces then it might be worn fork bushes...Thats a fork strip...

https://www.ronayers.com/oemparts/a/hon ... front-fork
Lowering the tone since 2007...
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Pete.L
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Location: Bristol

Re: Forks

Post by Pete.L »

Or wheel bearings.
Probably best to check the whole front end.
If it moves check it, if it doesn’t move check it anyway 😊
My new ride is a bit of a Howler and I love to make her Squeal
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Cadbury64
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Location: Auckland, New Zealand

Re: Forks

Post by Cadbury64 »

A shudder under brakes is more likely to be a disc that is not running true. The discs are easily tweaked by knocking them e.g. during a tyre swap. In my experience it is not the steel disc that bends, but the soft alloy carrier that supports them, and this can be very carefully tweaked back true with a bit of care and a pry bar. You need a dial indicator gauge set-up off the fork legs to find the high and low spots and figure out where to pry. Don't pry on the discs themselves! YMMV and all that.
2017 MT-10SP, 2019 Vespa Primavera 150
VTR_FIN
Posts: 6
Joined: Fri May 14, 2021 10:12 pm

Re: Forks

Post by VTR_FIN »

Cadbury64 wrote: Tue Jul 20, 2021 11:45 pm A shudder under brakes is more likely to be a disc that is not running true. The discs are easily tweaked by knocking them e.g. during a tyre swap. In my experience it is not the steel disc that bends, but the soft alloy carrier that supports them, and this can be very carefully tweaked back true with a bit of care and a pry bar. You need a dial indicator gauge set-up off the fork legs to find the high and low spots and figure out where to pry. Don't pry on the discs themselves! YMMV and all that.
This is exactly what I did to fix my front brake shudder. I measured 0.20mm of axial runout on the RH front disk, I corrected it by inserting a round steel bar to floater rivet/pin holes and prying them until runout was 0.03mm. Shudder gone, didn't have to buy new discs.
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Duffy1964
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Location: Orpington Kent

Re: Forks

Post by Duffy1964 »

I have just read on another forum that someone else had brake judder, it seems the cause was a worn wheel bearing, so worth checking


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Duffy1964
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Cptorange
Posts: 12
Joined: Fri Jun 11, 2021 12:56 pm

Re: Forks

Post by Cptorange »

There is very little tolerance in the brake 'buttons', so they easily warp and give the pulsing through the lever. Put light machine/penetrating oil on the buttons and stick them in the oven on your missus's best baking tray for an hour/ gas mark one. This relaxes the metal, and sometimes unwarps the disc. Worked on my old race bike before I went to race discs.

Remember to let cool before you burn your hands, and obviously leg it from the wife when shes spots whats gone on.
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alanfjones1411
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Re: Forks

Post by alanfjones1411 »

Cptorange wrote: Thu Jul 22, 2021 11:40 am There is very little tolerance in the brake 'buttons', so they easily warp and give the pulsing through the lever. Put light machine/penetrating oil on the buttons and stick them in the oven on your missus's best baking tray for an hour/ gas mark one. This relaxes the metal, and sometimes unwarps the disc. Worked on my old race bike before I went to race discs.

Remember to let cool before you burn your hands, and obviously leg it from the wife when shes spots whats gone on.
Or put a bolt through buttons and tighten a nut up on the other side and use an electric drill to spin them.
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