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After two years, 2x broken tab on the axle and still hanging up frequently despite several attempts at rounding off the brake cam and careful reassembly the right brake still grabs hard enough to lift the tail from 2-3 mph. Two tires have been replaced early due to flat spotting on the right side.

I tried to order the brakes on-line but this did not work so I called Sonex. They told me that I could not order the brakes as I was not on file as being the plans owner. I do not mind doing this (aside from the $100 fee) but the brakes are clearly on the list of Aerovee items that they will sell to the general public. Apparently the person on the phone does not understand this and had to ask her supervisor. I am for now refusing to pay the $100 because I am cheap!

In any case they should arrive soon and I hope to have smoother brakes soon. I tried all sorts of fixes to get the right brake to work and it still grabs very badly. The left side got better and better and is working well but the right side will never be 'right' it seems.

Is the bearing surface that the brake cam pivots within lubricated well? I don't think I lubricated mine at all (not sure if I overlooked the instructions to do so or if it isn't mentioned) until one started getting stuck during engine run-up. Disconnecting the brake cable and manipulating the arm manually made it pretty obvious that my problem was due to surface corrosion and lack of lubrication in there.

I've never completely understood the need to round off the brake cam--do the go-cart guys have to do this also? If so, why don't they come pre-rounded? Unfortunately, despite my skepticism, I also rounded mine (but only enough to knock down the point), so can't claim to know one way or the other. But, I'm pretty doubtful that your problem is caused by not being rounded enough.

Think the $100 to transfer registration with Sonex is an expense well justified, but if looking for options, put GP's brakes on mine before Sonex was offering their hydraulic ones. Work great. fit on Sonex axles. Made new backing plate that integrates caliper mounting and wheel pant mounting.

David A.

Brakes came today! Yea!! UPS took like a day or two for std service and Sonex got it shipped right after I responded to their estimate. I agree the $100 transfer fee is 'OK' I guess, but some of their products you DO NOT need a plans number and the brake kit, areo inj, hats, books etc are in that category and the person who took the order on the phone seemed unclear about the policy, or maybe I am wrong? I keep saying next month for the $100 transfer fee, some day I will want what it provides I hope.

Anyway I looked at the kit and it looks like it is all there. I read all the posts on here about the Sonex brakes and most seemed good with the kit. Some (maybe many) mentioned having to put in a 1/16" washer to keep the
brake pads from being too tight against the discs. I where would this shim washer go? It seems it must go on the axle. Anyone know. I would like to have one ready if it needs it. A few mentioned leaks or bleeding problems but I have worked on brakes enough that hopefully will be ok with this.

Started installing the brakes today. Got the old ones off. Changed the tires to Dresser Aero Classics. Mounted the hydraulic brakes and got the wheels back on. It seems the spacer is not used and the hold in the axle for the cotter pin is now out past the nut. Some of the small hardware is not included. Spent some time cutting the angle pieces and next session will try to run the hydraulic lines and get the handle and master mounted. 90% done and 90% to go on this project. At this point I am leaving off the plates to mount the wheel fairings.

Made the angle brackets from the plans in the shop on Friday and Sat mounted the master cyc to the aircraft. I drilled out five rivets from the angle on the left side of the plane and put three rivets in the outboard plate and then replaced the two other rivets. The inboard bracket is riveted directly to the floor. I did notice that the looking down installation view on the plans shows mounting the outboard angle bracket with 4 bolts. The full size plan view however shows three rivet hole. The rivet mounting feels secure enough but will see when it is actually working. Still need to install the hyd lines. I will probably use the routing of the cables forward of the firewall but it would be possible to mount then on the cabin side of the firewall. This might be cooler but more in the way of feet.

Today pulled the cowl and routed the nylon hydraulic tubes where the brake cables were. Bled the brakes and tested them a bit by rocking the plane. They seem to be working well. Hope to get the cowls and gear leg fairings back on tomorrow.

Added some spacers to the axles so the cotter pin holes would line up with the castles on the wheel nuts. Put the cowl back on and am ready to test.

I have all the mechanical brake parts in a box if anyone is interested in paying the shipping for them. Flat rate box will be not too much anywhere in the USA.

Test flight with new Brakes today. It was weird not to be afraid to pull the brake lever. They work as supposed to, nice and smooth. Somewhat stronger. Not sure it is worth it if your drum brakes are smooth enough for you, if not it is a good upgrade.

Great write up, thanks. I have a tri gear and brake install is coming up soon on my build and have been deciding if I should just go straight to the new hydraulic brakes. Sounds like there isn't a huge difference and maybe I should save my $400.