ESR 310 topend

[smokinwrench]

Have any of you guys that own one of these checked squish? If so what did you get? Mine has right at .090, that is way to much.

[riverrat]

Had not checked mine, but did you call ESR and ask what the squish is supposed to be? It may be different than stock.
What is your compression?

[smokinwrench]

Compresion is 155 and it hasn't been started yet

[riverrat]

I guess that should go up, once the rings seat. Stock compression to run on pump gas should be about 175. I would break it in, and do another test. Don't forget to re-torque all the bolts.
Then if your compression is good, I wouldn't worry about squish. People measure squish to see how mauch they can mill, and get more compression. I am guessing you are running the pump gas dome, so you shouldn't be worried about milling.

[smokinwrench]

I'm sure it should be WAY less then .090. Why leave it so wide it will hurt performance. People measure squish to eliminate that area around the edge of the piston, the fuel doesn't fire good on the outside. All of the firing needs to be done in the dome for best performance. So you measure squish, cc the dome, mill off dome to get proper squish, then mill out dome to regain proper cc for correct compression. I know its being nit picky but I want it to be in top tune. And yes I want it max for pump gas, I hate buying race gas.

[DixiePlowboy]

You're right , wrench....squish has more effect that just the compression ratio.

I've been thinking of ordering an ESR 310 w/trx9 porting. I'll be watching this thread closely to see what's resolved before I decide.

[dansvan]

Is it running a head gasket or o-ring?

[smokinwrench]

Oring

The porting is really just a clean up mine has trx9 porting. Supposidly the port work has been cast into them.

[JohnR.]

That sounds like its a bit on the big side to me too. I'll have to measure mine on my ESR motor when I take it out. I've read in a lot of places (not just here) that they don't put very much work into their portwork and that if you want to use the engine to its potential that you should order it without porting, save some money, and put it towards a proper port job.

John

[DixiePlowboy]

Oring

The porting is really just a clean up mine has trx9 porting. Supposidly the port work has been cast into them.

That's what I was afraid of and what had me hesitating. Sounds to me like the CT kit(with CT porting) would be a better deal. OR, better yet, send the Pro-X cylinder to FTZ.

[JohnR.]

I had an FTZ ported stock jug at 270cc on mine before the 330 and it was fast. I think the 330 is only faster because it is so much bigger and the ports are a much better starting point right out of the box.

John

[DixiePlowboy]

I've been a fan of FTZ for years. They definitely put out some good stuff.

That's where mine will go.

[riverrat]

There are so many factors in putting together a good running motor. Not just the piston and cylinder. For $600, you can't go wrong with a 310 kit. It is a great starting point.

[smokinwrench]

Yes it is a great starting point. Before the 310 mine was a full on drag ported 250 and it was unreal fast, but I wanted something more rideable with a 11 year old following me. Tough to ride trails when your shifting every 5 seconds.

Maybe I can get time to call ESR tomorrow, but from everythign I have ever known about a 250r is that .035-.040 is the perfect squish so I know the 310 can't be to far from that.

As far as porting I think I would send mine to C-leigh racing, he has noting but great reviews on exriders, r central.

[NOS_350X]

Really need some more setup infomration.

You running the long rod? a spacer plate? short rod? Which dome do you have in it?

I havent worked too much with the new ESR cylinders. The compression numbers there seem low too. If you have a spacerplate are you sure its the right plate and thickness gaskets in there?