Milling heads & piston ?

[rking1550]

My heads come in @ 102cc's, milled .008 already.
How much more can safely be milled off ? Would it be possible to get them down to 94 or 95 cc ?

If not that'll lead to a piston question. I'm using SE 120 pistons .010 over. Which I  think are 13.5 cc domes.. Is there a piston with a big enough dome to get me to 12.3~ on  compression?

Motor is a 120" SE cases, S&S flywheels with the 7.575 rod length. Harley 4.060 cylinders .010 over,
t-man thumper heads. Presently @ 11.3 & 662-2 cams. 135~ square..
Thinking about going to 12.3 compression & 662-3 cams ..
Any and all thoughts on this are welcome.

[barny7655]

Id look at head gaskets, see if you have some leeway there, if not pistons , looking at piston to valve closeness,different cams may help if looking at different  power curve ,gearing also may give you a different bike manners, its to be able to reuse the heads after getting down  to 95cc for different  application ,milder bike ,whats wrong with what you have ? what do you want ? knowing you want more bang for the buck,

[1workinman]

My heads come in @ 102cc's, milled .008 already.
How much more can safely be milled off ? Would it be possible to get them down to 94 or 95 cc ?

If not that'll lead to a piston question. I'm using SE 120 pistons .010 over. Which I  think are 13.5 cc domes.. Is there a piston with a big enough dome to get me to 12.3~ on  compression?

Motor is a 120" SE cases, S&S flywheels with the 7.575 rod length. Harley 4.060 cylinders .010 over,
t-man thumper heads. Presently @ 11.3 & 662-2 cams. 135~ square..
Thinking about going to 12.3 compression & 662-3 cams ..
Any and all thoughts on this are welcome.

I had a set of the T man heads and the    662-2 set to 200 ccp  in a 124 with a Rush Wrath and I think it made in the mid 140s square . If I were you I call Wes Brown and chat with him about his cams and tell him what you got . I seen the results of not checking valve to piston clearance by a shop   

[rking1550]

Id look at head gaskets, see if you have some leeway there, if not pistons , looking at piston to valve closeness,different cams may help if looking at different  power curve ,gearing also may give you a different bike manners, its to be able to reuse the heads after getting down  to 95cc for different  application ,milder bike ,whats wrong with what you have ? what do you want ? knowing you want more bang for the buck,

There's nothing wrong with what I have now,  mostly getting info for a "maybe" build. And gather parts if needed.   If I can just cut the heads that would probably be the cheapest way to get there.   

Head gaskets are .030 now.  And will be if I do this build
Thinking about a t-man 662-3 cam. Less than 12.25 compression I think it'll be too soft down low. I used the S&S 640 @ 11.3. And that didn't impress me,  made 140 hp. But didn't have a "hot rod" feel to it below 4k ish rpms. Don't want to go the again,  that's why I need more compression,  like 12.25~
Gearing is good , I've got the lower 3.37-1 primary gearing.

If I can get the heads to 95cc, I'd still be able to use them later in a milder build if I wanted to just by going go a smaller dome or flat top pistons.

Want I want is to have it all, low end tq and hp, and  a hot rod feel, and still have good street manners,  150 hp ??
Also want to be able to do 3-400 mile days.   

[rking1550]

My heads come in @ 102cc's, milled .008 already.
How much more can safely be milled off ? Would it be possible to get them down to 94 or 95 cc ?

If not that'll lead to a piston question. I'm using SE 120 pistons .010 over. Which I  think are 13.5 cc domes.. Is there a piston with a big enough dome to get me to 12.3~ on  compression?

Motor is a 120" SE cases, S&S flywheels with the 7.575 rod length. Harley 4.060 cylinders .010 over,
t-man thumper heads. Presently @ 11.3 & 662-2 cams. 135~ square..
Thinking about going to 12.3 compression & 662-3 cams ..
Any and all thoughts on this are welcome.

I had a set of the T man heads and the    662-2 set to 200 ccp  in a 124 with a Rush Wrath and I think it made in the mid 140s square . If I were you I call Wes Brown and chat with him about his cams and tell him what you got . I seen the results of not checking valve to piston clearance by a shop   

Wes Brown ? Is he the cycle-Rama guy, 630i cams ?  If so I have thought about trying it. Just didnt make any calls yet.
Also I'm running a CV 51  carb.   

[speedzter]

Once you start pushing duration and overlap, I wonder if you will increase the reversion at lower revs, and how
the CV Carb will cope ?
The thumper heads are based on stock castings ?
You would be looking at ~ a .040" cut to get where you want ?

I think with your plan, you won't see much gain in low/mid, but you will gain mostly up high.
Is that what you are really after ?

[kd]

This sounds like what you are looking for.  All the manners and aggressive power on tap. Unbelievable mileage and superb touring.


http://harleytechtalk.com/htt/index.php?topic=99409.0

[rking1550]

Here's a recent run. If I could keep or pick up a little before 4k. And gain high end hp. That's perfect.  But still want the hot rod feel when I twist the throttle.

[Don D]

It looks to be out of air at the top. The pipe choice will dictate the torque curve down low if the compression is high enough. More overlap is not going to help especially carbureted. I would be looking at cvo based heads if it were mine, very easy to get to 95cc.

[rking1550]

It looks to be out of air at the top. The pipe choice will dictate the torque curve down low if the compression is high enough. More overlap is not going to help especially carbureted. I would be looking at cvo based heads if it were mine, very easy to get to 95cc.

Pipe is a S&S sidewinder 2 into 1.
I think the heads are 110/cvo heads, but I'll double check on that.
Heads are done and on the bike now, I was hoping to just send them back to T-man for a cut & freshen up,  a long with a cam swap.

[1workinman]

My heads come in @ 102cc's, milled .008 already.
How much more can safely be milled off ? Would it be possible to get them down to 94 or 95 cc ?

If not that'll lead to a piston question. I'm using SE 120 pistons .010 over. Which I  think are 13.5 cc domes.. Is there a piston with a big enough dome to get me to 12.3~ on  compression?

Motor is a 120" SE cases, S&S flywheels with the 7.575 rod length. Harley 4.060 cylinders .010 over,
t-man thumper heads. Presently @ 11.3 & 662-2 cams. 135~ square..
Thinking about going to 12.3 compression & 662-3 cams ..
Any and all thoughts on this are welcome.

I had a set of the T man heads and the    662-2 set to 200 ccp  in a 124 with a Rush Wrath and I think it made in the mid 140s square . If I were you I call Wes Brown and chat with him about his cams and tell him what you got . I seen the results of not checking valve to piston clearance by a shop   

Wes Brown ? Is he the cycle-Rama guy, 630i cams ?  If so I have thought about trying it. Just didnt make any calls yet.
Also I'm running a CV 51  carb.

Yes a smart guy also .