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mixxer

CRF230F Port Work Considerations

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Tough question....
There really aren't "levels" to a correct port job...
They should all touch on every detail ... From Port texture to taper to valve seat cuts to short side radius design to guide cut and shape....
It's actually one of the biggest return for money spent mods when done right....
The only thing out of the ordinary on a correct and completely detailed port job would be the cutting for bigger valve setups....
My problem has always been with the rapist pricing charged for the work.... I can do a head from start to finish on most anything in 3 hours min to 5 hours max ( a bit longer for epoxy work ).…. I think the industry norm is to charge for port work on a scale that equates to "prison sex"... And yet most of those port jobs are hack jobs... Fact...
As Guy mentioned , Frank does very detailed quality work... And as far as I know it's his full time job...  I don't want to steal any work from anyone...
Keep in mind you DON'T need special valve guides or magic seat material.... That stuff Jack's prices up for zero measurable gain...
Give Frank a look up at www.xr100.com
Thank you for thinking about me though.... Appreciate it..
 


My two cents;

Well Mixxer there is “My level” and there is “Your Level” and I suppose that “Franks level” is some where in between...

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1 hour ago, adnohguy said:

 


My two cents;

Well Mixxer there is “My level” and there is “Your Level” and I suppose that “Franks level” is some where in between... emoji848.png

 

Lol...

What I mean by "levels" is that so many places will say things ranging from 

"Port cleanup"

To 

"Full asphault assault drag shredder agression port"

And it all doesn't mean shit...

You either match the port angles and shapes to get flow based on the carb size and valve size... And hit it all correct.. or you don't... Simple as that...

The real range in layman's terms of what most shops are selling is this:

Beginning

"Fluff n Buff" =  sand everything a bit and polish stuff for no reason...zero gain...but head is not ruined since nothing much was done...

All the way to:

"Sewer pipe hog port"  = where everything is done wrong and you can't fix it if you tried.. performance killed and head casting is wasted...

 

Edited by mixxer
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I'm sure that Frank's level is every bit as good as mine...

Plus he has better valve cutting equipment... 

So Frank wins!

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IMG_0121.JPG

IMG_0122.JPG

IMG_0123.JPG

IMG_0124.JPG

Mike Coe work from 2004 for a cam with .380 intake lift.

I have a head from/done by Frank but I never did a mold/sample for it yet.

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IMG_0005.JPG

IMG_0006.JPG


I purchased this used head on E-Bay and sent it to TM way back when we first started doing business together, he cut it up and sent me these photos.

Hopefully you “Do it your selfers” Like me, can get an idea of “ What not to do” when these photos are studied closely?

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IMG_0005.thumb.JPG.3811495bc6dc406cf48250a70980987d.JPG

IMG_0006.thumb.JPG.4451d879b5aaba443f5af703e7d1a0c7.JPG


I purchased this used head on E-Bay and sent it to TM way back when we first started doing business together, he cut it up and sent me these photos.

Hopefully you “Do it your selfers” Like me, can get an idea of “ What not to do” when these photos are studied closely?

I was about to do the same cut head with the one that was destroyed last year. Thanks for posting that pic Guy.

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Where would one consider to open up on these pics?


Just read every “Mixxer” post you can find and try to duplicate what he says.
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It's really too bad how little material there is between port roof and intake valve spring seat....

And look at that shitty short side radius on the Intake too....

Need to:

Raise the floor ..

And ...

Raise the roof...

To solve everything on this intake port....

What you would need is someone to weld up and re machine the valve spring seat area .... Find a source for a several mm shorter spring assembly with proper spring rate and travel....

And epoxy the floor and move that whole port "up"... Make it more downdraught / down draft style....  Fix that whole short side feed....

That's what I would do... If I could.... 

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Or possibly install one of these:

 

IMG_0498.JPG.69d425cffe95bd262ccb8a8c4f2b9826.JPG

 

1999 Suzuki DR 350 cylinder head.

 

(Nope cam chain is on the wrong side, won’t work. My Bad)

 

 

 

 

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13 hours ago, mixxer said:

It's really too bad how little material there is between port roof and intake valve spring seat....

And look at that shitty short side radius on the Intake too....

Need to:

Raise the floor ..

And ...

Raise the roof...

To solve everything on this intake port....

What you would need is someone to weld up and re machine the valve spring seat area .... Find a source for a several mm shorter spring assembly with proper spring rate and travel....

And epoxy the floor and move that whole port "up"... Make it more downdraught / down draft style....  Fix that whole short side feed....

That's what I would do... If I could.... 

So really there’s not much a back yard mechanic can do for himself but polish the ports some and call it a day?

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10 minutes ago, Titanman said:

So really there’s not much a back yard mechanic can do for himself but polish the ports some and call it a day?

No, there is a lot you can do, pretty much exactly as I outlined and photographed....

It is a really terrible port as cast... No performance consideration in it's design at all... Just utility....

Nobody does the port raise/ spring change.... So you wouldn't get the ultimate port from anyone...

Don't polish anything that flows intake charge.... Surface tension slows the flow like raindrops moving slow over a fast moving windshield... You break the sticky boundary layer with a rough surface.... More flow through same size port because now it flows closer to walls...

Polish = BAD....

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  Mix knows what he's talking about as demonstrated by his "venom" CRF250r build thread from a few years ago. Also verified by the transformation of the 'carbed'  CRF 250's port transformation from 04 thru 09. The ports got smaller with a higher floor and the power went up across the board. By the 09 model the intake port was virtually oval in the valve guide area. Which gets me to thinking:

  Since there's not much room to raise the 230's port roof then maybe widen the port to maintain sufficient area, then raise the floor with epoxy. You would end up with something similar to the 08-09 CRF250R's port. Nice radius on the short side, blend the oval into the bowl area, high velocity.  Hmmm? Maybe????

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There is just so little room to work in that torturously confined port...☹️

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All the action on this forum makes me jealous! I'm building Suzuki DR/DRz125-200 engines, and there is zero activity related to those happening on that forum. 

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Frank sent me straight to his source at Engine Dynamics for the large valve 230 head.  Mike at ED wanted $850 to do the job with a 34mm Intake and a 28mm exhaust valve.  Told him I didnt want to fool with the exhaust and it ended up being $426 for valve/spring kit and machining with me doing the assembly.  I believe I will hold off on that one for now.  

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1 hour ago, Titanman said:

Frank sent me straight to his source at Engine Dynamics for the large valve 230 head.  Mike at ED wanted $850 to do the job with a 34mm Intake and a 28mm exhaust valve.  Told him I didnt want to fool with the exhaust and it ended up being $426 for valve/spring kit and machining with me doing the assembly.  I believe I will hold off on that one for now.  

Holy Christ!!!

Who charges that freaking much money for a 2 valve head??

What's the shop rate?? $300 per hour??!!

When I was still doing work commercially on mostly 450s...

I would completely port with the more expensive / time consuming epoxy raised floor on a 5 valve Yamaha... Cut all seats for +1mm oversize... Fit the bowl dimensions to match...

And think I was so happy with the $550 I charged ($275 porting without big valves or epoxy).…. I was making about $100 an hour and happy as a clam at high tide....

Now I feel like a cheap hooker..

Lol

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Holy Christ!!!
Who charges that freaking much money for a 2 valve head??
What's the shop rate?? $300 per hour??!!
When I was still doing work commercially on mostly 450s...
I would completely port with the more expensive / time consuming epoxy raised floor on a 5 valve Yamaha... Cut all seats for +1mm oversize... Fit the bowl dimensions to match...
And think I was so happy with the $550 I charged ($275 porting without big valves or epoxy).…. I was making about $100 an hour and happy as a clam at high tide....
Now I feel like a cheap hooker..
Lol

This is why I have Chris Schumann hooking me up with some 1.5 mm intake valves. Also waiting on green human for availability through him as well. I’m following your instructions as I type. IMG_5657.JPG
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Awesome!!

You are going to be so happy with your own handiwork in the ports ..

 

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