Normal to have to change tuning after pipe?

[SmokinAl]

I had the stock muffler on my 26cc 001 and tuned it a little rich as it's still in break-in mode. I ran it around then changed to the tuned pipe (love the sound difference!!). Anyway, I had to really lean it out to get it to run after installing the pipe. Its still about 1 1/16 out so I think its ok but it wanted a lot more with the stock muffler. Is this normal to have to change the tune so much just from a pipe?

 

[atom3624]

Simple answer - YES.
Once set, it should stay +/- the same - not like nitro.

I've found with a tuned pipe I had to make a bit richer as the engine's breathing better (anti-clockwise a smidgen).
I would be surprised if you have to LEAN for a tuned pipe - screw clockwise a little.

Al.

 

[SmokinAl]

Ya, I definitely had to lean it out; maybe 1/4 turn. And I'm liking not having to fiddle with it so much like my old nitro!

 

[Whoduh]

If you were running it rich during break in (which is normal), you should have to re-tune after break-in.

 

[crankestein]

It would be "on most instances", normal to retune.
But not like nitro which is fluctuates with humidity, fuel, etc, although I still got my 1/8th buggies.

Contrary to what many say, I use airplane fuel, 5%, and is more than enough, regular castrol lubricant. Easy to tune, temps stay happy...