250x ported head ????

[Fordtrax]

Ok, Ive just recently rebuilt the top end on my 92 250x and used all stock components except for a mildly ported head with larger valves i purchased off ebay.
When i recieved the head i compared the intake ports and i dunno if id call it a mild port job?lol
And the reason i know the valves are bigger is because i had to take some meat off the rear allen key bolt in order to pass the top of the intake valve.
This bike has a stock pipe and muffler and stock air filter with no holes drilled in the lid and i didint even touch the jets in the carb other than cleaning them.

Well i fired it up last night for the first time and it runs real whisper quiet but doesnt like to idle right.
I can set it to idle either too high or if i just turn it just tiny bit it idles perfect but eventually dies.
I thought at first it was because the rings havent fully seated yet but i messed with it for a few 20 minute intervals and still doesnt want to idle right.

My question is with this head should i change the jetting in the carb?
Or is this head not gonna work with out bigger cam,aftermarket filter and exhaust?

I dont really want this bike to be some obnoxious sounding machine so im wondering if its possible to use this head or not?

Thanx......Marc

[maddmatt02]

Id guess the jetting would need to be richened, you got the possibility for more air flow with the larger valves and ported head.

and I am not sure if I uderstand right, you installed larger valves into the head, or you bought it done, because i dont know a whole lot but i thought yo had to get yor seats cut to utilize oversize valves.

[Fordtrax]

Yeah i bought the head with the valves already installed.
And i dont know much about valves and such so your prolly right! lol

[maddmatt02]

im almost sure they have to cut, because I dont thinik an opversized valve would sit right in a stock seat, plus if the hole isnt larger then there wouldnt realy be an increase of flow with the larger valve cuz when it opened the hole is still the same size.

I was reading it as you bought and installed larger valves into a stock head...

my bad.

but I know when you change the intake/exhaust part of it you need to change jetting, and although you still got the same exhaust, and the same intake system, airbox/filter wise but you still got a chance at more airflow with the headwork.

and now that thats done, you would really benefit from a pipe and maybe no airbox lid and a high flow filter.

and fresh rings shouldnt have anything to do with why it wont idle.

[Fordtrax]

Hey thanx Matt! Yeah I think im gonna just tear it apart again cause now im noticing and smelling a lil oil smoke so im thinking the head even tho everything looked like new probably needs the new valve stem seals installed. (which i skimped on) And while im at it i may just pay to have my original head rebuilt and sell the ported one.

[maddmatt02]

the oil might be from the rings not being broken in and seated yet? Id play with the carb and get it running right and then ride it for a while and see how you like it before you sell the head. unless you really think something is wrong in there and need to pull it apart to double check? and then of course if the oil burning doesnt go away youd have to tear into it.

[sadinkins]

do you want to sale the head or trade for good stock 1?