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Billy wisely ended up having someone else run the XL, despite the overflowing carb (wisely in not riding it himself, not in running it with the carb overflowing), just to get a few "break in" laps on it. Of course with it flooding out as it was, the results were less than spectacular. In fact, with my shop's name on the tank, it bordered on the embarrassing. Of course my wife Jane and I, our grandson Max, and our son Joe and his girlfriend Kristen were all sitting in the stands and thus knew nothing of why the bike ran so poorly. All we knew was that there was a problem. About that time I was pretty happy that I had not pulled the magneto when I installed the top end, because I would have been wondering if I had gotten it in a tooth off.
A bright spot was Billy's performance on his other bike, a Rotax powered machine. Billy came out and put on quite a show! In both his heat race, and the feature, Billy was in the lead before the end of the first lap and increased his lead on the nearest competitors with every corner. To say that he dominated would be an understatement. Billy's performance was all the more impressive when you realize that he is in his late 50's.

a really bad intake port. Now a bad intake port is one that flows poorly. A really bad intake port is one that not only flows poorly, but is missing material where it is needed to get good flow. Where Evolution and Twin Cam intake ports have a generous "hump" in the floor, the PP100 intake ports actually have a slight "dip" in the floor. Add to that the fact that each side wall of the intake port has a large "divot" across from the valve guide, and you have a head that is just plain begging "weld me ...WELD ME!"
about the same as the stock PP100 heads with a .100" smaller valve. Now if you increase the size of the Twin Cam valve to 1.900" (still .040" smaller than the stock PP100) and do a decent porting job, your flow will be about 243 cfm at .500 and 253 at .600". So, you can see why I felt the flow on a ported PP100 was disappointing, because despite gaining nearly 30 cfm, for the valve size it was dismal compared to a Twin Cam. In fact it is a little dismal compared to the 232 cfm at .500" lift that I can normally get from a Shovelhead (which incidentally uses the same valve diameter as the PP100).
Since the weld came right to the intake seat, I cut the heads for a new oversize seat insert, just to insure that the welding in such close proximity to the seat would not cause it to fall out at a later date. After shaping the newly welded in material to match the clayed up head, the heads were ready for the flowbench again. 256 cfm at .500" lift and 272 at .600 were the final results. More than 50 cfm gain over stock at .500 lift and 65 cfm at .600. Not too shabby. 35 cfm better than a Screamin' Eagle Performance Head. Like I said, not too shabby. Are they the world's best flowing Indian heads? They just may be. Is there potential for more? How much do you want to spend? 
Last fall a long time local flat track racer by the name of Billy Hofmeister approached me about doing some work on his iron XL heads and cylinders. Since I have recently seen a resurgence in interest in porting work on these heads, and have done a few sets in the last year, I agreed to take a look at his heads.
Seems like a natural, but truth be told, I may not have thought of it except for Joe, one of my customers for whom I recently finished a big twin Flathead stroker build. He had done research on coatings and had many of his engine components done. The whole idea behind ceramic coating is to put a heat barrier on the part to prevent combustion heat from "soaking" into the part. On his Flathead, we had the combustion chambers in the heads, the combustion chambers in the cylinders, the combustion chamber side of all 4 valves, the "back" side of the exhaust valves, and the exhaust ports ceramic coated. In other words, everything that is exposed to combustion temperatures. We also had the a teflon treatment done to the piston skirts.
eeded to get his motor wrapped up. Last Saturday I had Billy drop off the bike so I could do a "mock up" with clay to make sure there were no valve to valve or valve to piston issues. Just a very small amount needed to be removed from the intake pockets to give a little more radial clearance for the larger valves. Thursday morning I dropped off the pistons, heads and valves for teflon on the skirts and ceramic in the combustion chambers, exhaust ports and valves. Friday morning I picked up the finished pieces and started assembly. New high performance valve springs from Kibblewhite were in order, since with the porting work, the engine should want to rev higher.
So as of this writing the bike sets on a lift in my shop with just the carb left to install. I, for one, am pretty anxious to see how much the performance is improved with the increased airflow, higher compression, and a cooler running engine!
With the modifications we had made since the last race, there was no doubt that the bike was faster. I believe that Bobby lowered his own 1/8 mile national record with the first pass. The competition was much tighter than at other races, with other bikes running times close to our old record, but thanks to our new found power, we still had a nice cushion.

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