i think someone said 8 or 10% oil

understood,
much appreciated.....

I'll try to jump back in here with my lean issue. Acouple of questions were asked.
1. What engine = GX-5R orange head
2. Running temps = 180* to 200*

im useing a losi 4 shoe clutch, 2 composit shoes and 2 aluminum shoes, green and gold springs, mess with it for a while today trying to get a better tune and heard a bunch of rattleing noise, 4 loose fins on the head., what next

dude you should of let us know how much $ you were putting into that 3 port before you got $500 into it!...we could have hooked you up with a crank, piston/sleeve/rod set, and the orings ALONG time ago and you could of had a GX5R by now!...

im not a quiter!!!!! lol...if i was i would have stopped working on this long ago, are the fins coming loose a problem with these? ive seen a few go motors forsale on here and alot of them say they have loose fins but not interfere with the performance of the engine....bla...bla...., i did pull the carb out today and noticed the bottom o-ring in carb opening was torn and sticking out. i threw a nova head on it (dint like the rattleing noise) also bought some p3 and od97t today, also tossed a new rod in it just incase, im not giving up on it! thanks alot all for trying to help out, and as grizz said in past post "just being silly" well i can tell him what is silly and it's not me!!

once you get those orings i can 90% guarantee that your problems tuning will stop!...there was a good amount people who had problems with these motors and it was all mostly the OLD orings!...thats why the new GX series motors have the new orings!...you want to change out ALL of the old BROWN colored orings and put in the new black ones

sounds good, ill give it a try when i receive them

The torn O ring in the base where the carby goes wouldn't have helped thats for sure.
New O ring on the cards.
Put a little bit of after run oil on the very base of carby when you replace it and are putting carby back in so carby not pick up on it and be slow and gentle,

will do! thanks for the tip!

the broken cooling fins won't effect your performance, just cable tie them up to the top fins for now to stop them rattling like mine

Just noticed mine last night and one of my fins is broken.

Whats the cause of this??

Thanks
Simon

High resonance vibration from the motor.
Cut 4 x pieces of fuel tubing and fit them between the middle most fins on the front, rear and both sides.
The middle fins are the most affected by this vibration. The fuel tubing will stop the fins coming loose 80 - 90% of the time.
This is not an uncommon thing, and happens on a lot of nitro engines.
Another thing that can influence the fins breaking is if the body is touching the fins anywhere. Make sure your body is cut well away from the cooling head.

leave the front & rear tubing out to allow air flow through the fins, just the 2 sides need the tubing, something like this :-

Got my 2 66X's on their way from Mark, very excited to get these bad boy's broken in