Hey gang.

Any tips for methods of checking for front brake rotor warpage?

Im noticing some pulsing through the lever at low speeds. 

I have a dial gauge with a magnetic base but cant figure a way of measuring the rotating disk and ensuring its spinning true on its axis relative to the dial gauge. 


more info:
I recently (6 months ago) purchased some new floating disks for my 1100 front end. I got the cheapest I could find and they were Chinese aftermarket jobs. Also got some cheap Chinese pads

I think I may have been a tad over enthusiastic during the bedding in phase and caused one to warp. 
 Today I removed and dismantled my front callipers, removed the pistons and cleaned everything. Replaced all the fluid with new stuff.

The new cheap pads needed some filing out of the holes that the mounting pin goes through, as they were not quite lined up properly. Now they slide more freely on the pins. 

The pulsing is still there but seems to be significantly less. 

Ive used a straight edge to check the rotors for general flatness and couldnt notice any warping. But this is far from an accurate method Id say....

Get a piece of 5mm x 50mm flat about 75mm long and drill a 10mm hole in one corner. You can then bolt it to the fork leg with one of the caliper bolts, no need to remove the caliper, and there you have a steel platform to mount the dial gauge that wont move in relation to the disc.

aye !...sounds like  plan rick

good luck Floyd

Axial cupping, is something to also keep an eye out for, (where the top of the disc leans in and the inner most leans out just by a smidge but combined makes itself felt) It may have come up in the clutch thread one time cupping that is, but I'm sure I read about it back in or around 2014 with brakes.

Have a look at this
http://www.k11og.org/forum/viewtopic.php?t=12756
(too lazy to retype   )

Cheers ya'll

Ricks metal plate idea sounds like a beauty! Will give it a go this arvo....

(n a side note - but related to metal bar...  - The other day I fitted a paralever rear end to my K100. This required fabricating a simple bracket for the rear exhaust hanger. Went to the hardware to buy a small bit of flat bar....it was $20 for the size I wanted. Bugger that! So I wandered up to the various brackets used for timber framing and pargola footings etc....Found the right bracket with enough metal for my project and bought it....was $4! for just as much steel as the $20 plain bar.....crazy!)

Corkboy: Cheers mate. The first post in the link you sent me is exactly what Im experiencing. And the fact its reduced somewhat by me cleaning the disks and calipers makes me think its not warpage....but will check with a dial gauge this arvo....

Few year ago, my back brake overheated and the disk was slightly marked.
As a temporary solution I removed the wheel, put the bike in first gear and when the wheel was rotating cleaned the disk with a wet stone.
Normally, these stones have to be used with oil, but I opted to use gas in order to avoid any greasy deposits. The trick is to slide the stone in multiple positions to keep a flat surface.
A very good cleaning of the disk is required after this treatment. You don't want to get grits embedded in your brake pads.

The temporary solution worked so well that after at least 5 years, the same disk is still on the bike.