Author Topic: Can an Oil cause fork juddering on braking?  (Read 2337 times)

Offline RoyC

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Re: Can an Oil cause fork juddering on braking?
« Reply #15 on: 20.01. 2018 09:31 »
I'm a little sceptical that coarse emery paper will remove any appreciable amount from a well-seasoned, work-hardened steel brake drum. *conf*

It worked on my iron drum.
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Online KiwiGF

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Re: Can an Oil cause fork juddering on braking?
« Reply #16 on: 20.01. 2018 11:28 »
Hi everyone,

I'm resurrecting this old thread hoping for some advice. My 59 GF is back on the road and I'm now working through the little gripes to make it nicer to ride. One of the issues I have is the front brake juddering. The head races, wheel bearings and bushes/stanchions are all good but I've checked the drum with a dial gauge and there's about 0.10mm ovality - is this within tolerance, or should I get it skimmed? *????*

Cheers

Tim

Just my opinion but 0.1mm is just 004” so pretty round. Maybe check there is a chamfer on the on the leading shoe before looking at skimming.

I’ve managed to get good brakes without skimming just by making sure the leading shoe contacts the drum first, I’ve got pretty out of round drums on both my bikes, and not had juddering yet.
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Offline worntorn

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Re: Can an Oil cause fork juddering on braking?
« Reply #17 on: 20.01. 2018 15:29 »
I'm a little sceptical that coarse emery paper will remove any appreciable amount from a well-seasoned, work-hardened steel brake drum. *conf*

It worked on my iron drum.

Good to hear that this worked for you Roy.

Ive been suggesting this method for awhile after it worked to fix my SR 2ls brake judder.  Since then the Emory method has  improved the front brakes on the Vincent and the 650ss.
The more common method of drum trueing, skimming in a lathe, also works well, however the emery removes the bare minimum of material. Sometimes the lathe operator might chop off a little more than necessary.
The other benefit to the emery method is its DIY, some cost savings.

Glen
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Online TimK

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Re: Can an Oil cause fork juddering on braking?
« Reply #18 on: 21.01. 2018 06:50 »
Thanks everyone,

I'm going to try chamfering the leading shoe first and see if that works. I'll get back to you and let you know how I get on.

Cheers

Tim
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Tim Kerridge
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Offline wortluck

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Re: Can an Oil cause fork juddering on braking?
« Reply #19 on: 28.02. 2018 21:57 »
You use the brakes *eek*
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Online TimK

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Re: Can an Oil cause fork juddering on braking?
« Reply #20 on: 14.04. 2018 01:52 »
Hi everyone

I finally got around to chamfering the leading edge of the brake shoes and it's transformed them - no juddering and they work! I love a cheap fix.

thanks for the advice.

Cheers

Tim
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Tim Kerridge
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Re: Can an Oil cause fork juddering on braking?
« Reply #21 on: 14.04. 2018 10:17 »
Good one Tim.
No reason not to go here. https://sites.google.com/site/shoalhavenclassicmc/home
Lots of trophy's on offer (they took me ages to make).
Cheers
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Online Triton Thrasher

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Re: Can an Oil cause fork juddering on braking?
« Reply #22 on: 14.04. 2018 11:50 »
I'm a little sceptical that coarse emery paper will remove any appreciable amount from a well-seasoned, work-hardened steel brake drum. *conf*

Abrading ferrous metals is kind of what it’s made for.
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Offline Rex

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Re: Can an Oil cause fork juddering on braking?
« Reply #23 on: 14.04. 2018 12:55 »
Which is true, in the sense that "abrading" could describe the use of emery etc in engineering to clean the metal's surface of rust and mill-scale, remove burrs etc etc.
Unless M-S has got somehow "softer" or emery cloth upped it's performance to new heights over the decades that still holds true. What it never did was to appreciably change the dimensions etc of the parts it was used on, hence it's use on finished machined pieces etc.
Chuck up a test piece in a lathe and use emery/sandpaper/whatever for a period and see how much it's altered dimensionally.
Good luck to anyone who thinks emery etc would clear a ten thou ovality from a drum with a few passes. I suspect they'd run out of emery or arm muscles long before they reached the target of a true drum..
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Online Greybeard

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Re: Can an Oil cause fork juddering on braking?
« Reply #24 on: 14.04. 2018 21:30 »
So, could the emery be working by smoothing out the different diameters so the brake shoes are sliding without juddering?
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Online TimK

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Re: Can an Oil cause fork juddering on braking?
« Reply #25 on: 14.04. 2018 23:08 »
Musky said
Quote
No reason not to go here. https://sites.google.com/site/shoalhavenclassicmc/home
Lots of trophy's on offer (they took me ages to make).

Musky

is there a prize for 'The best not very original, totally wrong colour, oil leaking A10 with unmatched engine/frame numbers'? - I might be in with a chance!

 Cheers

Tim
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Tim Kerridge
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Re: Can an Oil cause fork juddering on braking?
« Reply #26 on: 15.04. 2018 01:42 »
G'day Tim.
You'll have stiff competition from my A7 plunger.
Cheers
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Offline coater87

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Re: Can an Oil cause fork juddering on braking?
« Reply #27 on: 15.04. 2018 22:04 »
 10 thousandth with emery paper?

 Sure, monks carve rocks with paint brushes too.

 I wouldn't want to do it, but the phrase "forever and a day" does come to mind. ;)

 Lee
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Offline worntorn

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Re: Can an Oil cause fork juddering on braking?
« Reply #28 on: 16.04. 2018 01:31 »
My SR had the judders bad. I probably spent a couple of hours grand total to get the drum trued with the Emery.
That didn't seem like a long time to solve an annoying and dangerous problem.
Didnt have to pull off tire, drive the wheel to some shop in town to turn drum, wait one week, pick up and remount tire. I've gone thru all of that a couple of times with other bikes.
In that context, 2 hours with the Emery strips is pretty quick.
And free. Almost.

Glen
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