I will have to give darkhorse a call this afternoon I guess. I would think something like that would always be checked when a crank is reworked. I know they installed new rods, pro-plug, welded, trued and balanced. This was all done on a stock 2002 crank.

I will also try to find out about the pistons today.

 

Okay, talked with John at Hoban. Figured out that the pinion can't be wrong, because it would have showed when we degreed the cams. We tested it with a degree wheel, as an assembly, and it was all good.

Pistons: 20 degree with dish, 8 cc dome volume. I don't know deck height or gasket thickness yet.

 

I knew it wasn't the crank; Hoban did the work and they would not make that kind of mistake.

The 8cc dome volume changes the compression picture and gets closer to the 210psi you measured. With 0.00" deck height, .030" head gasket, 67G cams and 89cc chambers static now jumps to 11:1, (higher than 10.6 per Axtell) corrected to 9.76 and CCR to 206psi; we are close enough for government work. All those numbers are higher than I would run or recommend for a street build but the motor should be a tire shredder. May be a little touchy to tune; higher compression motors are more difficult to dial in. But at least we are back to "compression is not the problem"; that's progress.

I would be talking to Axtell and looking for the closest competent tuner skilled in tuning carbed builds; they aren't that easy to find.

 

Update: I was going to haul the bike up to Hillside. I talked with them on the phone a couple times, and if I had it to do over again, would have had them handle it to begin with. That being said, I let Axtell talk me into taking it to Flora Racing Heads for one more shot at tuning. I went where they asked me to because I figured if they found something mechanical wrong, it would help my case, plus they are only 3 and a half hours from me.

Dropped it off Monday. Tuesday evening he called me and said we are now making 122.3 Ft-Lbs of torque at just over 4000 rpm, and 110.8 max horsepower at about 5500 rpm. His first run confirmed the previous dyno at 104 horse. The previous torque of 135 was just a spike, with no known reason.

These are numbers I can live with. I like that the torque is about 95 at 2500 rpm.

Picking it up Friday.

 

Thanks for the update; good news.

 

Awesome man! Sure am sorry for what you had to go through. The results are exactly where I put our builds at. +1 hp per cube with gobs of torque! If they give you a dyno sheet, post it up!!

 

I have a sheet, but it is a little hard to read because it is a crappy fax. I will post it after I get a better copy on Friday.

 

If it makes you feel any better, my 107" Axtell build is making 108hp and 119tq. I am using stock heads ported by WFOLarry with 1.9 intake and 1.625 exhaust valves. My deck height is .004" with .010" base gaskets .030" head gaskets and 82cc heads. Should be around 10.5:1 I am using a R&R615 cam.

Their advertisment of 130/130 is just plain crazy. Not a street motor IMO

The same build dyno'd at 110hp and 122tq last year on the same dyno.


Below is my most recent dyno sheet after I added a 34hp shot of nitrous.

 

I am pretty happy with where I am at now. I can't wait to get it back and ride it! But, now I have to start messing with the new Yamaha, and then I have to look for another Harley to apply everything I learned this time around. I think I want to try another twin cam, used, and try to do some of the work myself.

No matter what, this build with the 107 is over. If it gives me anymore trouble, we are gonna through out what we have done, and go for broke. Even if the old engine goes on the shelf with the beer cans.

 

Glad you got it figured out!
Scott