330 esr pv overheating please help?

[ledperformance]

Make sure the inner o-ring is not leaking. Any scratches on the head can cause the o-ring to fail. Run only race gas. Detonation can cause o-ring failure.
 Do a pressure test to make sure you have no air leaks.
A one inch id tail pipe will cause it to overheat at full throttle. If you are lean around 3/4 throttle opening it is because you are using a DGH needle. Change the pilot jet to a 50, try a DEJ needle in the 4th from top clip position and start with a 182 main jet. a 182 should be plenty rich. We usually end up with a 178 main jet.
It has been my experience (only about 30 years) that the combination  of pump gas, DGH needle and a 1" tail pipe would give you exactly the result you are experiencing.

[jcs003]

sounds like an air leak.  wont idle and overheats rather quickly.

john

[The Phantom]

What octane Did they recommend for your application.

When I asked Tom for a pump gas dome with my +4 stroker he recomended against it.  He said "you dont want to run pump gas" He originally told me that I could mix 50/50 (pump gas with race fuel) but then called me back about an hour later and told me that I needed 100% race fuel.  Now when I got my kit I seen they put a race dome in my head.  Tom recomended the vp110 or the c12 fuel.  I run the vp110 and run around 200-205 degrees.  Takes about 2-3 minutes (warmup before ride) to get to 150 and then SLOWLY climbs to the 200 degree mark.  After checking your o-rings as mentioned above I would get yourself some race fuel.  Even if you mix 50/50, if in fact it is a pump fuel dome you have, it may make a difference.

Also I thought the water jacket issue was more on the non-powervalve engines because of the extra alluminum that was not hollowed out in that area.  At least thats what I had read somewhere about that. The small stinger issue is not an issue IMO.
Becarefull when you put the o-rings on your cylinder deck.  Do not roll them into the groove they need to be set into the groove.  Dont want them twisted sitting in there.  If you tried all thats suggested and nothing works I would definitely call Eddie.  My guess is he would want the oppurtunity to make it right than have bigger problems down the road like a p.o. customer.

[trx250scar]

OK guys Thanks for all the great info and response on this. I work a lot during the week so this weekend i will be tryingpthese suggested fixes this weekend.  Will give updates as I eliminate potential problems. .

[trx250scar]

Make sure the inner o-ring is not leaking. Any scratches on the head can cause the o-ring to fail. Run only race gas. Detonation can cause o-ring failure.
 Do a pressure test to make sure you have no air leaks.
A one inch id tail pipe will cause it to overheat at full throttle. If you are lean around 3/4 throttle opening it is because you are using a DGH needle. Change the pilot jet to a 50, try a DEJ needle in the 4th from top clip position and start with a 182 main jet. a 182 should be plenty rich. We usually end up with a 178 main jet.
It has been my experience (only about 30 years) that the combination  of pump gas, DGH needle and a 1" tail pipe would give you exactly the result you are experiencing.

should i perform pressure test with exhaust off and plugged there and carb off with the gauge at the intake boot? i also forgot to mention in first post i am running br9es and castor 927 32:1. i will pull the head inspect dome for any markings indicating pump or race fuel. either way i will try some race fuel. i currently use only ethonal free 93 but will try some 110. also will go ahead and order some o rings in case they r damaged when i get in there. any suggestions on were to pick up a dej needle? also was thinking how would i know if the pv was not opening properly while the rpm increases? could this be an issue?

[ledperformance]

You must plug the exhaust, the power valve and the spark plug hole. You can pressurize though the intake to 12 psi. I should hold pressure for 15 minutes with little or no loss of pressure.
If you have a good compression tester you can check cranking compression. I need to be a good gauge, I prefer Snap-on compression testers. With the engine cold, hold the throttle wide open and kick until the gauge needle stops going up in pressure. Anything over 180 psi should be straight race gas. many of the engines like yours have the piston coming out of the top of the cylinder, because the cylinder is made for a 72mm stroke and is to short. This give a very poor combustion chamber. I think good fuel is important even if the compression is not high on that type of engine.
We stock DEJ, DEK, DEL needles.
If the power valve is not raising the engine will not have much top end power, or rev out.
You may want to call me so I can better explain how to proceed in trouble shooting this issue.

[Langbolt]

You say you've got the Clip in the top groove in the Needle ? That's the LEANEST setting.....move it down to the 3rd or 4th position

And Like Arlen & Jon Suggests.....do a Leak-down test....if you can't hold 12 psi for 15 min then you've got an air leak and that will make you run LEAN - and raise your operating temps.

Good luck & keep us posted

[C-Leigh Racing]

Make sure the inner o-ring is not leaking. Any scratches on the head can cause the o-ring to fail. Run only race gas. Detonation can cause o-ring failure.
 Do a pressure test to make sure you have no air leaks.
A one inch id tail pipe will cause it to overheat at full throttle. If you are lean around 3/4 throttle opening it is because you are using a DGH needle. Change the pilot jet to a 50, try a DEJ needle in the 4th from top clip position and start with a 182 main jet. a 182 should be plenty rich. We usually end up with a 178 main jet.
It has been my experience (only about 30 years) that the combination  of pump gas, DGH needle and a 1" tail pipe would give you exactly the result you are experiencing.

I dont think this thread will spin off in the wrong direction as some do on .net, but I would like to point out to all of you, just above where Arlan states (only about 30 years) that means we all need to take note of what he has to say, because in those years of working on 2 strokes & TRX250R engines, a man can learn a lot & more than likely hes speaking from what his hands have touched & not what is read from a book.
The only other person that I would put up beside Arlan when it comes to knowing a TRX250R engine, Allen at CT Racing, both those men are like 250R Gods in my book. If I just knew 1/2 of what they have forgot over the years, I would be pleased to no end.
So, lets take notes what he replys, cause you can trust it works.
Neil

[ledperformance]

Thank you Neil for the vote of confidence. Means a lot coming from a man of your experience.
There is more than one way to build an engine. I am sharing what I have learned doing it my way, and what I have done to solve problems I have seen. Hope my advise helps.

[kt23]

Allen - very smart but would lie to u in a heartbeat. I have zero respect for him. Just my .02
Arlan- straight up guy and always willing to talk.

[trx250scar]

thanks for all the input guys

[C-Leigh Racing]

Allen - very smart but would lie to u in a heartbeat. I have zero respect for him. Just my .02
Arlan- straight up guy and always willing to talk.

I know thats right about Allen, but Allen needs to be understood, like when you call its like if you cuss at him everything goes smooth. I never did cuss & still got good help from him like we were on the same wave link.
Now miss Roxann, Allens wife, heck with Allen, just let me talk to her every time cause shes just as good as he is at answering questions.

Thank you Arlan for what you add, but far as my experience, well, all I know is from hard knocks trying this or that to know what worked & what didnt & really climbing into everything I touched, but being poor, most of the time I had to take nothing & then use that to make something out of it.

Thank you as well for the AMA/ATVA EDT sponsorship at Busco Beach. Was good to see a quad with L.E.D grafics on it competing this season, so hope you'll be back next year.
Neil