We are trying to upload pictures of the "testbed" (ref "testbed trauma" thread in airplane crashes). It's actually a homemade 1.20 size "stick" with a McCulloch 32 cc chainsaw engine converted and installed, that my son calls "frankenstein". It has about 1-2 hours actual flight time on it, with nearly every flight ending in a "deadstick" landing (still working on that), and of course one "emergency landing" from about 60 feet, which resulted in minor damage to the airframe, and required an "engine change" due to severe damage to the engine impacting the ground upon separation. The project is still under the engineering process,,,trying to decrease a severe vibration problem, and of course the idle thing. This has been an excellant project for me and my son that we have enjoyed immensely. So.....here goes (I hate computers, and have a very hard time getting them to do what I want them to do). Hope you enjoy

I have a Bridi Stick with a Homelite 30 that is very much like your set-up that I've been enjoying lately. I also have two 32 McCullochs that are not presently on a plane. I'm just a sport pilot so I've only done the loop and roll type stuff with it. It certainly is different flying a bigger heavier model. Most of the time I can grease it on with either a 3 point or a tail high main wheel touch down. The engine will idle handily at 1700 so at idle the 18-8 acts like a brake. You have to bring it over the fence with a little power and then chop the throttle. I must be lucky, it's never quit on me?

I'm sure you enjoy yours very much. And may there be many more hours to come.

Jim

I run a ryobi on a bandito grande. Had lots of problems at first with dead sticks but finally solved it with the fuel mix. I was originally running with 50:1, real bad idea. Was ok until it was cowled. Worked it down till I got to 28:1. Runs great in the cowl and have'nt had a dead stick in about 20 flights. I also use a 18x8. Will definately do some more coversions.
Edwin

We modify engines in several ways fundamental to carburetor operation.

The most serious is the removal of the air filter and air box (plenum chamber). Two stroke engines are always pulsing air at the carburetor inlet. The prop wash and air flow across the carb inlet carries a large portion of the fuel charge away. The fuel charge is not carried away in chainsaw configuration. On a high humidity night shining car lights on an idling engine will allow one to see the halo (looks like a smoke ring) being forced out and back in the carb. It is an interesting phenomenon to watch. It is entirely possible that the engine cannot be richened enough to compensate for the loss of fuel charge. Making a very temporary air filter out of scrap foam might help lower the loss of fuel charge. Engines with cowls probably don’t loose as much charge. A velocity stack helped my engine, which is also open to the air stream. You might also consider that the airflow around the carb inlet is different on the ground than in the air. It might be necessary to set the carb adjustments for in air operation rather than best ground settings.

Is the engine going dead at low or high throttle?

Hope the information will be of some help.

Hey BILLS...
The engine runs fine in the air, and even idles nicely in the air. The only time it actually dies is after roll-out on landing. Seems like the more I run it, the better it gets....Thanks

That one is easy. Occasionally my gasser takes a spell of wanting to quit after landing. I simply assumed that the throttle was set too low and the wind was turning the prop. When the wind stops the prop stops.

When it starts doing that I cheat and throttle up two clicks immediately after the tail touches down. Works every time.

Sure it's funny that Frankestein, it looks a very good idea to test your engines!

It is a great testbed....gonna eventually pull off the mac 32 and put on a homie (something bigger than a 25 cc though). Still looking in pawn shops....

12-01.....bought homelite "super II" chainsaw from pawn shop, have mounted and running already, hope to fly today.....

12-03....Flew today, See "New Homie for Frankenstein" thread.....