Hi Joel,

I just happened across the latests posts here just now. The innertubes you ordered are about to get dropped off at lunch today. You should have let me know you had one with a bulge, I would have just sent a replacement out for you. I will provide a partial refund for the order you just placed.

On a similar note, it was common that you could inflate these to 10", the quality has been slipping among all the inner tube manufacturers (it doesn't matter inside a tire like they are intended to be used, but it shows when just an inflated innertube). I recommend inflating them over a ruler until you get to 9" diameter, I haven't seen any lumps/bulges in my tubes under 9". At that point you can go a 1/4" at a time on each tube and double check for any areas that look like they are going to get swelled up and stop or even let out a bit of air. If you over-inflate the tube and cause a bulge, it will likely be there somewhat even if you let air out, so it is important to inflate in small increments after 9" diameter and do both tubes at each increment. You could feasibly have one tube that makes it to 10" perfectly and the other which will start showing some tendency to bulge at 9.5", if you let out the air from the 10" tube to match the 9.5" tube you will probably notice the tube you let the air out of being "softer" or less "firm" as the smaller one. Inflating them stretches them like you would stretch a ballon to make it easier to blow it up.

Your Duck is looking good, Keep it up!

Greg

P.S. Stefan, I was looking forward to seeing you at NEAT, I assume you couldn't make it. We got the Sport in the Sunday afternoon demos and flew our new electric CricKit as well. Unfortunately with all the kits I packed I couldn't fit my Agri-Duck.