Tires and Brakes
This post is out of chronological order, I drafted it about a year ago but forgot to post it.
The 13×4.00-6 2-ply wheelbarrow tires that came with the kit are, in my opinion, too narrow and too weak of side walls. Two other sizes are frequently used on this airplane, 15×6.00-6 and for people wanting a “bush” tire an 8.00-6. Carlisle makes both sizes the bush tire is their “Turf Glide” golf cart tire and the 15×6.00-6 is available with many tread patterns. I went with the 4-ply 15×6.00-6 ribbed tire.
After mounting the wider tires I discovered that they were rubbing on the brake caliper. To alleviate this I used a couple washers between the rims and the rotor adapter. But that caused the rotor to rub on the caliper slide pin.
To fix the side pin I drilled out the caliper mount so the slide pin spring retainer washer can fit inside the mount.
Next I put a washer into the slide pin under the caliper mount.
Now the slide pin is recessed by the thickness of the washer giving enough clearance for the rotor. Another solution would be to modify my custom caliper mounts. I think they could be moved back about 1/8″ Also a wider rim would likely eliminate the need for the washer behind the rotor adapter and the caliper mount modification. But changing to wider rims would require replacing the axle and adjusting the length of the wing struts, not something I want to do at this point.
After a few taxi tests I’m happy to report that the brakes are working and holding up great. When using the brake lock on the lever I can run the engine up to around 3000 RPM without moving. With full pressure on the lever I’m able to run up to max RPM without moving.
Ultralight Builder 