Home ported heads question...

[xr50racer]

I think its funny all the people who claim to do port jobs on their heads but in really have no lcue as to what they are doing.



I wont even send my head off to a well known engine builder if they cannot show me a dyno graph of a head they have done and perfected to gain maximum power.



Call up any reputable engine builder and if you ask about a motor they are not familiar with, they will tell you and in most cases tell you who can build one good for you.



If an engine builder says ya ill do it for you no problem. I would be very leary of what he does. Hes probably making a quick buck.



Granted on these little heads it would not hurt to clean a little up here or their, but in all reality porting the stock heads still leaves you with super tiny valves.



Its like one of the engine builders who advertise for 50s saying they 3 angle grind the valves blah blah blah. That will not improve crap on the stocker head.

[PlanetMinis.com]

[manwhore]

I think its funny all the people who claim to do port jobs on their heads but in really have no lcue as to what they are doing.



I wont even send my head off to a well known engine builder if they cannot show me a dyno graph of a head they have done and perfected to gain maximum power.



Call up any reputable engine builder and if you ask about a motor they are not familiar with, they will tell you and in most cases tell you who can build one good for you.



If an engine builder says ya ill do it for you no problem. I would be very leary of what he does. Hes probably making a quick buck.



Granted on these little heads it would not hurt to clean a little up here or their, but in all reality porting the stock heads still leaves you with super tiny valves.



Its like one of the engine builders who advertise for 50s saying they 3 angle grind the valves blah blah blah. That will not improve crap on the stocker head.

dont you have a dyno i will be up there for the vegas race i will put my money were my mouth is will you??? i just did a 6 hour port job on my Takegawa twin spark head how much money you want to put out on the table against my porting and we can post it on Plenetminis.com also well!!!!!!

[cyclerider57]

I think that would be cool. You should do that. We plan to dyno my quad when the motor is back together and even my 50 sometime soon. FYI: a 3 angle valve job is not done to increase a lot of horsepower. It is done to make the head flow better past the valve. It will help a stock head, because you have to do it (at least redo the valve seat) after a motor has had a lot of time on it or you will get blow by past your valves. All heads start stock at one point in time (unless something like ultra head). My crf450 head is stock so are you saying that a valve angle job will not help it even though we increased valve size and ported it? You are wrong if you think that. I don't think that is what you mean, but I figured I would throw it out there. (I think you mean if you keep the valves, ports, etc stock then you would be right.)



EDIT: I reread your post and you were talking about a stock xr50 head. My bad.

[NoBars]

its a fifty for gods sake, i did all i can.

that .015 maybe didn't do much but it allowed me to mill it as much as possible, flycutter touched both seats...its not like i paid to have it done, there are advantages to being a machinist, pay is not one.



by doubling displacement it is almost impossible to hurt flow, you may not help it but...



I have some clue what im doing, right after I was done with the 50 I put my 1428 cc GS Suzuki together,. went 8.80s right off the trailer, all muscle street bike. spraying it will run in the 7s

[crf50kid]

in the 7s no way r u serus?

[LogiKal]

Spell check.

[crf50kid]

in the 7s no way are u serius? u happy

[NoBars]

fifteen thousandths of an inch.



in a chamber that small it probably makes a difference. If it doesnt who gives a shit? its funny to say, like it was some big time build.

I have some seriously fast bikes, this is just a little POS to get me around the pits. i wanted to make it fun to ride.

I milled the head .035 (Thirty five thousandths of an inch)

[LogiKal]

Nope.



"In the 7s, no way, are you serious?"

[NoBars]

yeah 7s at 180 with an old fat bald guy on it, street tire no wheelie bar.

(shootout bike)

built in my 1 car garage.

[cyclerider57]

Got a time slip? What is your best time? Must have to roll on the throttle so you don't spin? Is it a street legal partial drag tire? I bet it is also hard to keep the front end down on that thing. I love the drag scene. The action is intense. We have two Harley's running on nitro.

[NoBars]

yeah, i got a lot of em.(time slips)



best so far on last years setup is an 8.18



you gotta ride it, you dont just hold it wide open like a bar bike. the m/t street tire hooks almost as well as a 7" slick so traction is not a major concern. it does carry the front wheel to around the 1000 foot mark sometimes. last year on one pass it had the front end around 3 feet off the ground at the top of 4th and was rising. I ran out of nerve and chopped just enough to get the front wheel down and still ran a 8.208. the incrementals showed it shoulda been a 8.0

[bansheedude]

do any good porters that no what they r doin live in northern california around sacramento?

[Ozzy_Fiddy]

This is an old thred...........

[mxracer728]

This is an old thred...........

lol, captain obvious /\

[bansheedude]

i decided to try to port it on my own can some one tell me exactly what to do from beging to end because im confused . thanks