ESR 330pv water passages?

[trx250scar]

Does the passages above the exhaust port look to need milled?  I am going to ship back to ESR. I tried a lrd big bore pipe and it still ran 200 and it was only 60 outside. At a loss. Don't know What I am looking at there but there is barely any opening there. Hope the camera captured it.

[udontknowme]

if esr does any more design changes i recomend they look at the ktm250 for ideas. i dont think i seen mine get above 130* last summer

[C-Leigh Racing]

Kinda hard to tell from the pics, but looks like that cylinders coolant jacket, is closed up a bit more than normal.
What some are doing, taking a long shank carbide & opening up a bit more down under the head stud casting & a bit just above the PV part, so more flow can pass over the top of the exhaust port.
Lets see a pic of the head as well, make sure the head only has small holes at the rear over top of the intake area.
Neil

[rsss396]

The last picture makes the cylinder look OK, IMO

[F-Red]

Oscar, that looks very familiar to others, that have had cooling issues. I opened that area up, over heating problem, solved.

[trx250scar]

Kinda hard to tell from the pics, but looks like that cylinders coolant jacket, is closed up a bit more than normal.
What some are doing, taking a long shank carbide & opening up a bit more down under the head stud casting & a bit just above the PV part, so more flow can pass over the top of the exhaust port.
Lets see a pic of the head as well, make sure the head only has small holes at the rear over top of the intake area.
Neil

I have already shipped it to ESR so I cannot take any more pics but the head has the same pattern of long holes to match the cylinder. No small holes.

[trx250scar]

Thanks for all the opinions. Talked with Eddie and He seems to think the water passages will not effect it. Idk What to think. I just want it fixed. I will keep u posted on What He replies to me.

[etccb]

I am 98.9% sure that all esr billet heads have smaller passage cut to the rear over the intake, always have. There were other companies that did oring style billet different but it wasn't esr. Take a look at this area and under the dome again trx250scar and you will see it. I think all that ever searched for added cooling over the ex were the non pv with pv like yours not needing more flow there. Solid casting vs being cut out for the pv related to expansion or something like that. But esr did start opening that up 6 months ago or so when they started to cut the base nut seats. I think they got a new tool or something and while playing with thier program made those changes if I remember right. Anyway it deffinatly would never hurt to open it but don't know if it is a problem for you.

[rsss396]

I responded to your first question which was "do you think it needs milled", it hard to say with the pics you took but the 3rd pic looks like there is enough water jacket around the stud to feed enough water near exhaust port area.
But after rereading you then state that the bike is running hot, well milling out the water passage over the exhaust port will NOT fix overheating, infact it should add more BTU's to the cooling system. When have not enough cooling around the exhaust port like you asked about, you will normally have piston heat problems but that will not be seen on a gauge that will be seen with piston scuffing or seizure

[trx250scar]

I am 98.9% sure that all esr billet heads have smaller passage cut to the rear over the intake, always have. There were other companies that did oring style billet different but it wasn't esr. Take a look at this area and under the dome again trx250scar and you will see it. I think all that ever searched for added cooling over the ex were the non pv with pv like yours not needing more flow there. Solid casting vs being cut out for the pv related to expansion or something like that. But esr did start opening that up 6 months ago or so when they started to cut the base nut seats. I think they got a new tool or something and while playing with thier program made those changes if I remember right. Anyway it deffinatly would never hurt to open it but don't know if it is a problem for you.

maybe i just dont remember what it looked like in the head. i wasnt really focusing on that so i may have missed the different hole sizes.

[etccb]

Cool, no big deal you will see it. The cut outs in the billet are just smaller in the rear for less flow then the front. I didn't read the other thread but I assume the new large stinger style bb pipe ran the same temps as the b. I hope you find what is keeping your temps up soon.

[trx250scar]

Cool, no big deal you will see it. The cut outs in the billet are just smaller in the rear for less flow then the front. I didn't read the other thread but I assume the new large stinger style bb pipe ran the same temps as the b. I hope you find what is keeping your temps up soon.

the lrd bb pipe ran 200. my trx5b ran 220+ if i let it but it was 95-100 out when i ran the trx5b and it was only 60 out when i ran the lrd bb. so i am sure if were the heat of the summer the lrd bb would have had the same 220+ temps. like i said eddie says he is willing to help me figure out my problem. thats why i shipped him my cylinder. i guess we will start there. i am deffinately not saying there is something wrong with my cylinder just want to rule that out of the potential problems. the thing that gets me is how are so many guys running these esr motors with no trouble and only a small few of us see these issues. bad luck i guess.

[rsss396]

Can you measure the stinger size on the 2 pipes, is the ESR pipe actually 1.25 o.d. Like the LRD

[trx250scar]

The ESR pipe fits inside the lrd bb. I think the lrd is 1/8" bigger id. However I cannot measure it as I sold it.

[zcarlson12]

This is what my head looked like when I took it off before I did a complete rebuild on my motor for reference. Hope this illustrates the holes they are talking about.