Introducing the new - "QZ" RR-1

Mudhen wrote:After Kim ran his RR-1, a bug was put in my ear. It’s ready to fly, me thinks.
Kind of a lengthy post, but I thought some might enjoy it.
Lates…
Mud
BTW - just so you know, I blame Kim for all of this. Crummy bug in my ear!

Mudhen wrote:Thank for the nice comments, folks.

andrew wrote:Too much heat and fuel boiling becomes a problem, unless it can be dissipated.

And how. On a couple of occasions the engine abrubtly stopped. As if someone flipped a switch. Fuel starting popping out the vent tubes and I could hear fuel/oil sizzling on the inside.

fit90 wrote:They are still slowly getting better even after the initial five ounce break in.

This one is getting better too. When I started taching the engine it barely made 12k. Now it steadies at 14, with only 10% nitro. I think it will continue to improve.

Kim wrote:Bwahharhar...dark laughter from "Kim the Bug Chucker"

That's funny. But on a serious note, Kim, have you checked your meds? I can't be the only one here wondering about you.

Mud

Mudhen wrote:I had to do another teardown and overhaul on the "QZ RR-1." But I think it was worth it. I was shocked to discover just how much exhaust residue formed on the cylinder wall and piston. This informs me that although the upper engine was designed for a muffler, once pressure builds inside the chamber, it just can’t efficiently remove the spent fuel and oil. This, of course, increased the wear on the engine, (I had to replace the crankcase and crankshaft,) and severely reduced performance. I believe the RR-1 was designed to “get up and go.” It may have been a novel idea to install a muffler, but in the end I’m only restricting what could be pretty cool design performance. On the upside, I switched fuel to Power Master 20/20 and running temperature was radically diminished. I could touch the engine at low rpm without getting burned. I think I’ll leave the muffler installed, but run it wide open. It was a fun project and lesson learned. Next?
Mud

Admin wrote:Not an image host issue. Some years back, Mud went through and edited out most of his posts for reasons which are still unknown.

Boats13 wrote:I was staying quiet in reply. I feel bad that I brought it up, now. That is a lot of work. Something must have really angered or hurt him. His posts seem brilliant. Not as prolific as some, but always a good contribution, at least all that I have read.

CT