Ok, tried a search on this but didn't get the answers I was looking for.

I have a bit over a gallon ran through my new Evader ST, and I've noticed something that concerns me a bit. At cold engine temps the pull start puts up a pretty good fight when trying to start it. Feels like I still have a very good amount of compression. But, when I take her out and rip a couple tanks through her, and drop the piston to BDC before she cools off, it seems like there's not nearly the same amount of compression. Is this a sign of an engine wearing out? Or am I just getting to the point that I'm well broken in? This is my first nitro, so I really have nothing to gauge it by.

As a point of comparison, with the engine at room temps I can lift 2-3 tires off the ground with the pull starter before the engine cycles. At warm temps she'll pretty much stay right in place maybe pulling the 2 side tires up with the pull starter.

She still runs great, but it appears at warm temps she's not nearly as tough to pull on as she was during break in.

Any tips, or info would be greatly appreciated!

Thanks!

that is normal. as you heat the sleeve it expands faster than the piston and loosens up.

It's just metal expansion. Metal expand at higher temps and this is normal. The sleeve os made from a brass/chrome and the piston is made from a forged aluminum. The brass sleeve with the inside of the sleeve being chrome expands more then the piston does. Dont be worried with with just over a gallon of fuel through it you have some time till you start to loose compression if you broke in the engine properly. I have over 7 gallons through my one and it's still going good and has a ton of compression. So you still have a while till you start to loose compression to the point where you may consider a rebuild.

Awesome, thanks guys! I've always thought it never hurts to be a bit paranoid on things such as this.

The sun is out, and it's dry for the first time this week. Time to melt some rubber!! [8D]

The only "NEWB QUESTION" is one that goes unasked.

One of the best(In a good way) questions I've herd.

The science behind it is..... actually not the sleeve expanding and a looser fit, it is in there at the same fit, because the piston also expands and is engineered to expand at the same rate. its is much easier because the metal is softer and can be compressed easier. It is completely normal and not to be worried about.
and yes, very good newbie question, i am SOOO sick of "can i stick a os 30 and a 12 speed in my evader?...."

Dann

Looks like my Avatar got highjacked! [>:]

i thought it WAS you when i first glanced

Dann

You've been de-hijacked! Now I'm sure I've probably hijacked someone else!