My RB C6 tuning help?
 

after a few runs and with my motor at operating temp i bring it in and it idles high for a few seconds then idles low.. then if i let it idle too long it really loads up, i get on the throttle and a big huge cloud of blue smoke and a lot of spitting a sputtering, one time it cleared itself out then the next 2 times it stalled. I was able to fire it right back up. what is going on that my idle is quircky? i have tried to lean it a tick, didnt really seem to help but after a few runs i can hear the low end, the dreaded ZZZZZZ that these engines make when running lean. I immedietly richen'ed it back up. i even tried to fatten up the low end a little but the high idle still is there then it falls to a low idle.. what are your thoughts? It is a RB C6 BB 7T with a 2045 pipe and a 192 header. I run 30% odonnell fuel.
also forgot to mention, It has brand new ceramic bearings front in back just installed. and no the front bearing isnt leaking.
other than this idle situation this engine is an animal!!

its a C6 it wont ever hold a tune!! i had one and threw it in the trash hated that engine!!

but all joking aside it sounds like you have the top to lean and the bottom way to rich!! try leaning the bottom and richening the top, that should solve the problem. also run a P3 plug and check your bearings, they are bad for going threw the inside bearing.

what about the c5 does that hold a tune, i just got the hobby 9 5 port same thing as the c5.

never had a C5 or even seen anyone with one, personally im not a fan of RB with the turbo button head, they are harder to tune for some reason, but the standard plug ones are amazing. but i heard once you get about a gallon to two gallons on the hobby 9 it looses its tune completely and you have to start over then it holds its tune for forever.

well thats great to know ! its a standard head by the way.
i only use one # glow plug all year though , i dont switch to a cold plug i use a meduim hot plug.

youll like it, i thought about getting one for my buggy but im liking my Alpha so ill get another one for my buggy.

woops also forgot to mention, I am running P3 plugs..

im using it for my truggy by the way.

I have a RB s7 that i bought used, it ran pretty good then i put a turbo head on it along with new ceramic bearings. now it runs sweet! almost thinking of running that this weekend?! however i am getting the runtime with the c6 though.. just if i can figure out the idle thing...

the C6
also i had the sleeve pinched about a week ago, this is my 4th tank of fuel through it since the pinch.. the entire engine has about 2-2.5 gallons through it, i even put a new rod and ceramic bearing in it along with the pinch.

You shouldnt be running such a hot plug in the C6
Try something colder like a RB or Nova 6-7 or an O'donnell 97-99


Why did you have the engine pinched after just 2gal?

Ive had afew C6's now and mine are only stating to wake up at the 2gal mark. i have 15gal on one of mine and its still got compression

I love the C6

simply put, anyone who says they don't hold a tune simply does not know how to tune and setup the engine ! They are picky on plug/pipe , but once you have that right these engines are excelent ! Everyone always wants to blame the engine, never do they question if maybe they might be doing something wrong...I have tuned dozens of these engines and never had a problem.....

lol, most offroad RB's ive seen had the same result. guys were chasing tunes in 90deg weather, simple plug change to the P3 was the remedy.......maybe thats why my lhss cant keep em on the shlef

yeah the C6 i had was making me mad, i have never had problems tuning an engine!! engine tuning is easy except for that engine, the WS7 with the turbo button wasn't that hard to tune but it constantly needed to be tuned an hour here or there with the change or temp out side. i liked the power and runtime of the C6 but hated tuning the stupid thing, i would get it perfect and then i would shut it off and crank it up for the next race and it was off tune again. switch from an RB 6 plug to a P3 helped.

My C6 USA wasn't difficult to tune, just different than my other engine brands. I use the 2045 pipe and a OS P4 plug. My speed tunes one way, JS is different, FMS different, and on and on. Most of the problems stem from having the idle gap way off. When the idle gap is set correctly, the top end is easy to tune for upper rpms and the low speed can then be set to idle. When i was taught that all my motors became much easier to tune.

it cant be any harder than tuneing a novarossi, i mean rb are made in the same factory.