Paint Help

I am working on chopping and painting a Harley fender for a guy. I have chopped it and painted it 4 times and still having problems. I painted and did body work for a living almost a year ago (now I only do it on the side) and have never had this problem. I prepped the fender after chopping it, and used all SPI primer and clear with SPI reducer and activators. I first epoxy primed it with SPI and let it sit for a day to dry and breath out before wet sanding it. After it was wet sanded and prepped I hung it up in the garage which was well heated and heated the metal to room temps. Precleaned with solvent and water (glass cleaner that I've always used with no problems) based wax and grease remover. Sprayed my 3 coats of base with correct flash times between coats. Let the base dry a few hours and sprayed the clear. Everything mixed correctly, all new materials with Nason black base and then tried PPG Omni base with same problem. The base and primers went on perfect, not a single problem there. As SOON as I sprayed clear it went on and tiny tiny bubbles all over and then pinholes when dried with bubbles underneath. I did my first medium coat and then second wet coat like always. I have used this clear many times and sprayed it the exact same as always. Iwata LPH 400 gun with regulator and water trap at the gun, 20 PSI with 3 turns out on the knob and medium fan.
I have sanded it all the way down and started over and still the same problem 5 times! I even got to the point that I just went to do single stage and give the guy his money back since I am repainting it orange in the fall (if he even lets me now that I am taking so long) so I figured "hell, I will do single stage, give him money back and tell him that when we do the correct color then I will do it all over again". Layed the SPI SS down and SAME THING!
The primer nor base coat did this, only clear. It bubbles AS SOON as it hits the panel. I dont know what to do. I've tried everything from switching paint to new clear and activators, etc. Only thing that is old is my reducer which is about 1 year old and was opened but sealed correctly. I have no clue what to do here. Any oppinions or help is greatly appreciated!

Call SPI and ask your questions or get ahold of Shine on this board.

I have contacted Barry Kives from SPI and did everything he mentioned and same thing with all the comments I got on the SPI message boards. Did everything they said and still having the problem. Only thing I can think of now is old reducer (I didnt think 1 year old or a bit older reducer will cause this) or something in the line of my compressor. Thing that I am not sure of though is if it's moisture then I thought my moisture trap is ok and also my base would give problems and it's not. I took an air nozzle and no water came out while holding the air on, there was no moisture at all and I never use oil in the air line either for tools.
They told me to let the base coat flash a whole day in the sun to let the solvents breath out and I did but still, same problem...

I've never used that paint system, but every time I have had this kind of problem in the past, it was from stacking the clear too heavy, or too quick.

For those who may be shopping for a system ...today I use a Marhyde Ultimate Primer, Sherlaq sealer, R-M, HOK, and Xotic color coats, with R-M Diamont Clear. When necessary, I use Dupont 222S adhesion promoter, and either HOK SG100 or Xotic 34-200. After using this combo over 10 years, I just don't have any problems any more.

I have never had problems with this though. All I use for primer and clear and reducer is all SPI. Base I get from a guy off SPI forums in NJ which is R-M and high quality stuff. I have always used PPG and then tried DuPont a few times and their chromabase was fine but didn't care for it too much and then tried out the R-M he sent and like the stuff. I stick to the same stuff usually because it's what I know and never have problems with. I switched from the nason on this fender, stripped the fender down and use PPG and still, same problem. The clear was not put on heavy at all. Medium coat then second coat a wet coat. First medium coat started to bubble RiGHT away. I even tried a light coat and same thing. I used older clear at first and thought that was the probelm so bought new clear, sanded it back down and started over. Same thing with the new clear. I let the fender bake in the sun for a whole day and then put it in the shop, kept at room temp with a little Holmes heater next to it.
I have painted cars, hoods, bumpers, golf carts and everything in my garage with no problems ever. Now this is happening no matter what I change.

Try someone else s compressor and make sure there isnt silicone or oil in the air. Oil can come from the compressor with out an oiler.

Thanks for the info, I plan to do this tonight and tomarrow. I am stripping it after work and then priming it... Will wetsand and paint tomarrow. That is the only thing I can think of.