Got the ported Airsal kit working and I am not to pleased with the results for all the work I did on it. I had 0.035" milled of the top of the cylinder(due to lame tolerances), 0.8mm squish clearance, WPC of the Piston, Cylinder and rings, heat dispersing coating on the outside of the Cylinder and head, TBC coating on dome.
Porting is raising the exhaust port 3mm, the transfers 2mm, straighting out the intake and exhaust ports, smoothing insides of the transfers, especially where the splitters are, trimming the Piston skirt on the intake side 2mm. Combustion chamber is polished.
Here is my list of lame stuff with the Airsal kit, takes a different short reach Spark Plug, no mention of this in any sort of instructions, ruined an expensive iridium plug and possibly damaged the Piston (I could see it gouged a deep hole in the dome) when I tried to kick it over hard the first time with a bunch of four letter words, bad nikasil, plating had to get redone, porus casting had to fill with JB weld to avoid air leaks, lots of core shift on transfers. Don't recommend the Airsal, go with some sort of Puch kit and make it work instead.
Carb is a Delorto 19mm PHBG on a custom intake manifold. Jetting is 83 main 35 pilot, needle in leanest position. It was faster on a 82 main but engine sounded like it was detonating so I had to richen it up. (maybe the compression ratio is too high the airsal chamber is really small compared to stock, not to mention the milling). The intake manifold I had made is probably too long for tuning for the RPM my pipe and porting want.
Pipe is a Simonetti Puch pipe and its probably too radical for this Engine. Porting, pipe and Intake Manifold probably don't match too good.
I am dispointed in the mid range power, low end is ok but its dead in the middle and the top end is pretty good, hits a powerband starting at 40 mph and pulls until the speedo needle spins all the way around and hits the zero peg. Didnt know it would go that far! I guess this is way over 50 mph. The engine is screaming, I am worried that it will blow up. I am running 26/22 gearing. I don't want to go to a 27 front because it will take forever to get through the boggy mid range.
We really need to find a good way to raise the shift point for these built engines. A shift point of about 35 mph would make this haul. Anyone have any ideas, I am running a green first gear clutch spring on the second gear clutch but this isn't enough. Anyone try to lighten the clutch shoes or something?
Sorry I didnt get a GPS reading but the clutch blew up on the first run where I got the jetting close and I was going to use the GPS next but boom. Probably we need to figure out a stronger clutch as well. Anyone ever figure out how to improve a Tomos clutch?
I am sorta disappointed, I don't think this is much faster than any other big Bore A55 even with all of my extra little tricks, I do weigh 200 lbs though.
Time to get a spare case, weld it up and bore it so I can run a Gila cylinder on it. 65cc doesnt cut it.