cylinder head cutting question

[yeahright09]

How much is too much off the bottom of head chamber area?
had some work done and head specialist said he had taken .080 off the bottom nd sid he is coming up to large on chamber he will have to remove more. I said ok, cause he wohld know ho much to take off, but when i got the head back i measured the head at 3.625.
I read on hear that the heads are 3.75 tall. That means he took .125 off the bottom..? Wow

[dsvracer]

sounds like a bit to much. what are the cc's of the head after all the cutting ??  you will have to resize the intake manifold to fit in place, also do not forget to check valve to piston clearances.  Pushrods might also be an issue.  would have been smarter to just use a piston with a dome. good luck.  dsv

[aswracing]

DSV is right ... you really want to set the CR with the piston and use head decking for the fine adjustment only. Done in moderation, head decking is totally manageable, but done in excess it has all kinds of undesirable side effects like manifold fit, exhaust fit, pushrod length, piston to valve clearance, brackets not bolting up right, etc.

[Homeward Bound]

Why on earth?

Sure the standard fixed pushrods won't do.

But, still, we can all learn from this ... have you measured the squish clearance, and chamber capacity?

Would you be able to retrieve it a bit by using thicker base and head gaskets? Was it skimmed before and then he skimmed it again without measuring? If so, that would come down to his negligence.

I'd want a good explanation of what he thought he was doing, why, and what he did.

There is a balance between chamber size versus squish. You want some chamber size in order to fill it with charge.

Has he bathtubbed or re-shaped the D-shaped chamber at all?

.125 sounds to me like .080 taken off a head which already had a reasonable .045 taken off it previously.

What bike have you got, what performance package (e.g. cam), and what result were you after?

[kristian]

DSV is right ... you really want to set the CR with the piston and use head decking for the fine adjustment only. Done in moderation, head decking is totally manageable, but done in excess it has all kinds of undesirable side effects like manifold fit, exhaust fit, pushrod length, piston to valve clearance, brackets not bolting up right, etc.

one of the most logical posts in a long time!!!!  i hear of people maching heads like its a normal thing to do!!!  compression changes are done by piston changes and fine tuning by re-surfacing/gasketing.  bastardizing an engines components is ridiculous!  best example.  i spoke to cam manufacturer and they told me to machine my heads

[prodrag1320]

some folks don't want to pop for pistons,even then,we wont do more than .060.but totally agree with the piston first & fine tune with milling small amounts

[Hillside Motorcycle]

As far as manifold fitment, which is one of the largest concerns, one can re-face the intake manifold mounting pad, if set up to do it, and it quite easy once jigged/fixtured to do so.
No bastardizing, really, as if a specific set-up is being sought after, so be it.
FWIW, Wiseco offers a 19cc domed piston.
Scott

[HD/Wrench]

DSV is right ... you really want to set the CR with the piston and use head decking for the fine adjustment only. Done in moderation, head decking is totally manageable, but done in excess it has all kinds of undesirable side effects like manifold fit, exhaust fit, pushrod length, piston to valve clearance, brackets not bolting up right, etc.

one of the most logical posts in a long time!!!!  i hear of people maching heads like its a normal thing to do!!!  compression changes are done by piston changes and fine tuning by re-surfacing/gasketing.  bastardizing an engines components is ridiculous!  best example.  i spoke to cam manufacturer and they told me to machine my heads

Kirby  I agree  ,.. Pistons are the correct way to increase compression in larger amounts its really that simple.    No reason to take the head to the now defunct NASA lab for set up and measuring    I fail to see the reason to work so hard and do more work than is needed , and create other issues.. Intake fitment is one problem what about the others..  Fix one and you get to deal with the several others you created..  Upside is that today there are more pistons and dome set ups then ever before. 

[Homeward Bound]

bastardizing an engines components is ridiculous!

I don't want to distract from the original post ... I am interested to find out what was going on and why, and how the shop is going to make good on this ( ... Hey, I know ... let's J-B Weld an old dollar onto the top of the piston!!! ... ).

But, yes and no to your comment kristian. The "no" being that the engines are not exactly made as they should have been or were designed for optimally in the first place. I'd say a lot of the basic "performance mods" are not really performance mods at all, just making the engine go properly. And then you can update and improve to using today's standards, equipment, standards and materials.

Didn't the factory by default send out the -P police models with 50 off the heads and 12 of the barrels (or something approx)? I'd guess that gives a hint of how the engine "should have" been if not for EPA etc.

But, back to the OP please ...

[yeahright09]

I had measured the clearances and all seem good.
The heads cc'd at 67. We had to cut the valve pocket in the piston for the exhaust valve. Only about .010 more toward the edge. The builder wanted to use the weisco flattops. So we had the chamber welded to a bathtub. We reused the stock valves, and found a set of 1.725 rockers for cheap. We put the rockers on the intake only. I also did a lot of searching on the forum here and it was a very close call between ev-27 and w6 cam we went with w6 cause the head machinist was confident he could get the compression up. Well turns out he was a little to high on his ego and had to sent the heads out a second time to make the chambers smaller and ended up taking a bunch off the bottom anyways. (Hind sight, should have went with the ev-27.
I got some pics of the head. The only thing we did extra to the heads were polish the chamber a tad and put sighn grooves in.

[Hillside Motorcycle]

Wiseco also offers an 11cc dome.
Yes, flatops warrant a good cut on the head, as they are at a minus cc with the valve reliefs, even to establish a 9.5 cr when using a larger valve, with a reverse-tulip on the back of the valve.
Scott

[yeahright09]

Pics

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[yeahright09]

Intake

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[yeahright09]

Before polish

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[yeahright09]

After

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[yeahright09]

With base gasket. No head gasket. Lifters bottomed in the bore

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[yeahright09]

We had to take almost 1/4 inch off the pushrod tube locks(keepers) whatever you call them.
we shipped the compression releases with the head and didnt get them back.....he said he would send out a set and we never got them. Also found out he sent out a set of goodson releases, we had shipped him SE releases. So we arebit dissapointed in his organization skills. So we never got the set of releases we sent him and the ones he said he sent in the mail. We called him back and he said that he would send a check to replace the releases. I had told him $85, cause at the time of purchase they wer 85 bucks, BUT HAD NOW FOUND OUT THAT HARLEY RAISED THE PRICE TO $98.
this build has been hell. the engine builder recamended Don, but at the time Don was so busy we wouldnt see the heads for 8 or 9 weeks. So we decided to go with the guy who said 2.5 weeks. Ended up being 7 weeks....
I SHOULD HAVE JUST SENT THEM TO DON. and waited.

[HD/Wrench]

I have to say that is one of the more odd set ups I have seen. The port work pictures is completed?? Looks like areas that are still in a semi finished state.

I am sure at this point you would have been so happy with a piston swap to increase the compression.  Well I hope after all of this your builds does produce good power.

[yeahright09]

On a good note.. the engine fired up nicly no smoke, no bent valves, and no leaks..
did a 5, 10, 20, 40 second heat cylce. Took it offthe lift and rode it easy for 5 miles. Let it cool. Then took it out and busted a move till i hit 4k rpm and let off to let the engine bring the bike down in speed. Did this couple of times. Im going to take it easy for 500 miles not going over 4000. Do an oil change at 300miles.
BTW it dint take much throttle at all and spun up fast 4000 rpm.
CCP is 203/204. Carb is set at 46pilot and 180 main. It seems to like it.

[yeahright09]

I have to say that is one of the more odd set ups I have seen. The port work pictures is completed?? Looks like areas that are still in a semi finished state.

I am sure at this point you would have been so happy with a piston swap to increase the compression.  Well I hope after all of this your builds does produce good power.

yes pretty odd.
The story is this engine had some port work before. Of wich i didnt know about. Turns out the dealer had done some work some time way back. The heads were stock height when we began and had i think 12cc dome. At any rate the heads were ported. The machinist had put in new seats and had to match the seats to the exsiting  port. So that would explain the beed blasted area and rougher area around seat inside port. He did do a flow test, however it was just on one head and he wrote the numbers down on the receipt (not very profesional if you ask me. At 550 lift they flowed 165 he said that was good?
What are you guys thoughts?

[HD/Wrench]

It would depend on how inches that test was done at. If its 10 then thats huge if its 28 well not so much 

[DresserDan]

Didn't the factory by default send out the -P police models with 50 off the heads and 12 of the barrels (or something approx)? I'd guess that gives a hint of how the engine "should have" been if not for EPA etc.

Has any one been able to verify this? I had a 1990 FXR model EK that was suppose to be a CHIPS bike. When my builder done the heads he ran into the pushrod almost to long. He called a local H D dealer who he was friends with and the dealer told him that model had already had heads shaved at the factory. Also different ignitions. Don't know if this is true or not but have heard this story before.

[Hillside Motorcycle]

Chamber DOES NOT look at that odd whatsoever.
Reminds me of the welding that Branch used to do in those heads.
Sounds like it sound roll good.
Scott

[stroker800]

Bathtub designed combustion chamber,,,,many heads out there using design...HD is doin twinks with them..I mighted tried 6 Singh grooves,,3 per side..Keep us informed and up to date if going to dyno...I have a desire to also alter combustion chamber..
Dave