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New guy from Maine with a Rotax 503 engine who needs some knowledgeable help.

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Joined
Dec 26, 2013
Messages
11
Location
Maine
Hello My name is George Gallagher from Maine.

Now I do not have a Ultralite, but I do have a Rotax 503 engine, with Mikuni carbs, freshly rebuilt, belt driven in my SCAT hovercraft.

Well I need some tuning help on my 503. I have no one to help me besides the internet. My craft is very boggy/lagging on the bottom end. Once past that it seems ok.
Here is a link to my youtube channel so you can see what I am working with.
SCAT 1 503 Rotax Water running! - YouTube

Any idea what I should be idling at?
What is max safe running RPM?
What do you all typically run for jetting, and where are you needle clips at?
I mix my fuel 40:1
Right now I am running 300 jet n the ear, and 280 in the front f I remember right.
I think all of my problems are just to not having the motor tuned correctly, it always seems the motor has to be run at WOT to provide enough power to propel the craft, It should be able to carry two full size men, in the winter it will, due to no friction. In the summer on the water t will not.

I have adjusted the props for pitch to get the right rpm, (which I can not remember what that is)

Anyway I hope someone can help. very frustrating. I get t tuned right, I think I will be golden.

Thanks everyone

George
 
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