It isn't going to hurt your fork.

A slightly loose headset will not make a rattle... it will just be less stiff than normal. Make sure it is as tight as you can make it without restricting motion.

Is the issue happening only once per wheel revolution, or more often?

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formerly rruff...

Yep, I did that - there was a tiny bit of pulsing/shuddering under brakes, but quite nelagible. Her carbon/alum fork is nearly 200g heavier than my full carbon fork. Perhaps that extra heft adds to it's stiffness

@MileHighMark
That would be a good cheap solution! Nice - ill give that a go before I do anything drastic. Thanks!

Cool, I rechecked and re-preloaded the headset bearings - still pulses.
I can't ascertain it's pulse frequency - it only pulses at higher speeds, so it's difficult to perceive. I'll see if I can grab an old tyre, paint a nice large bright reference mark in one spot and do some trial runs....

What were your thoughts to to the pulsing frequency?

If the pulsing is due to the brake track being uneven in width in one spot (usually at the joint) it will be very noticeable at low speeds. Try it on a steep downhill while going slow.

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formerly rruff...

I had this same problem with a set of 7801 wheels I bought off ebay (now we know why he sold them). Both the front and read pulsed and I tried sanding the rims, etc. I finally decided that it was a variation in the hardness of the brake track. I found a new front rim on ebay that I guy bought for a project and never even laced it up. I relaced the front and it was fine. The rear pulsed less than the front and I just live with it. The wheelset has several thousand miles and the rear still pulses.

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For certain parts stiffer is more important than lighter.

Double check that you don't have something sticky like Coke (dried) on the rim.....Wash it with lots of water and a few drops of detergent. BTW....Kinlin rims are Scandium enhanced, aren't they??...Cool stop SALMONS dude!!! (NOT Black!)....these pads (salmons) look after your rim. After you've tried water as your solvent, If this doesn't work, try a non-polar solvent (Benzene, thinners etc) and see if there is any difference.
Don't laugh re the coke....I had a mate who darn near killed himself with a sticky front rim......it took us ages to figure it out!! the rim looked (and felt) absolutely normal when having a look at it.

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Used to race....got too wrinkly and old Updated: Racing again! Thought this was unlikely! Eventually, I may even have a decent race!

I think the 7801 rims were scandium enhanced also. I even wet sanded mine with a diamond whetstone (from my ski tuning tools) and there was no change. I wonder if scandium has issues with this?

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For certain parts stiffer is more important than lighter.

Niobium.

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formerly rruff...

I think the pulsing is occurring more than once per revolution and decreases in severity when I'm going less than, say, 10kph...

The pinned joint is actually very very smooth without any sharp edges, so I'm pretty sure that's not the cause...

Reckon I should still use Salmon pads?

Another update, I swapped with a mate's Ksyrium Elite front wheel, did a few Kim's and a variety of stopping pressures: nice and smoooooth... My mate also reported that there was a bit of pulsing from his Speedvagen ( with my front rim), but definitely not as severe as when he rode my bike with the shitty rim. So it sounds like that the full-carbon Specialized fork that I'm running, is also a bit flexy....

I didn't have great joy with Koolstop Salmon, on American Classic rims though. Plain black Swiss or Shimano pads are a good baseline, if they don't work, Salmon won't do any magic, as far as I experienced. Doubt the choice of pad will affect the shuddering much, in any case.

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Bikes: Raceur, Beateur

I'd be happy if I could source AC 420 rims by themselves... I've had a set before and they weren't too bad...

Agreed regarding the AC420s, but there are lots of interesting (wider) alternatives these days.

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Bikes: Raceur, Beateur

Salmon pads are recommended for Kinlin rims.

Have you thoroughly cleaned your rim and pads?

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formerly rruff...

I cleaned my rims (hot water and Meguires car wash) and gave the brake pads a bit of a scuffing with some 100-grit and it alleviated the pulsing a little, but it's definitely still there. I've got a set of salmon pads coming soon - hopefully that'll help a little more...

As long as my full-carbon Specialized fork isn't going to snap on my and send my front teeth into the road, I'm relatively happy in just tolerating the pulsing since I like my White Industries hubs so much.. If worse comes to worse after a trial ride of Hotham at the end of Feb in preparation of 3 Peaks, I'll borrow a mate's Ksyrium wheel..

Really wish I had read more reviews regarding Kinlin rims BEFORE I bought them....