Must Read before installing a billet FW on a Predator

michael whiteman

Well-Known Member
Local time
4:05 AM
Mar 2, 2021
ARC is not telling you the whole story. You'll want to know this before proceeding. If I had know this I would have not wasted three days. For $165 I feel the installation information is really lacking and every YouTuber has a somewhat different story. After talking with Jody (who makes the videos) at ARC, I was able to get the answers that were not included in their videos that were made many years ago. BTW today June 2024, the only place to buy a billet FW is from ARC the manufacturer and OMB Warehouse who is their only stocking dealer. All the YouTube videos show this installation with no why is mine the only one that doesn't work. Jody said he has heard of my issue on 212cc engines but not on 79cc engines like mine.

After lapping the FW to the crankshaft and torquing the nut to 55 ft/lbs I proceeded to mount the coil with a .250 spacer so the core legs were centered over the magnet. Now the fan shroud housing hits the coil requiring .250 spacers behind it also. The videos explain this clearly. Next I installed the recoil starter assy. and to my disbelief when I pulled the rope it did not engage, only made this clicking noise. C'mon now! This wasn't in the video.

Fast forward a day and a half. Out of frustration I painted the inside of the drum..........I call it a cage because it has 6 window openings into which the 2 pawls protrude. After pulling the rope a few times I could see where the pawls were scratching the paint. The pawls are .500 wide and a portion of each were hanging totalyl outside the cage with no way in hell they were going into the window openings. I considered buying a second cage and cutting it in half. Then I could tig weld it on the factory cage and effectively make the window opens larger solving this whole issue. You guessed it! Predator does not offer the cage as a replacement part. The next idea I had was to remove the spacers behind the fan shroud which would move the pawls .250 closer to the cage. Then how do you address the problem with the coil touching the inside of the fan shroud? The only answer is to take my Dremel Tool with a cut off disc and cut a big opening around the coil. Now everything will clear and should work fine but how about all the air that will be escaping from this new opening? But then again............what about all the air that is escaping from the .250 gap all around the fan shroud due to the spacers. The fan shroud was designed so you wouldn't put your fingers in there but more importantly to create an air flow over the fins when you stopped at a light and not moving. We're kinda defeating this purpose huh? I drew it all out as to were I would cut before going to bed.

When I called ARC and talked with Jody for the first time this morning this is what he said. When they first designed this FW everything worked as the old video shows. Over the years Predator has changed, ever so slightly, their fan shroud housing creating some of the issues, like mine, seen today. OK, I'll buy that but here's the shocker.........................He said to remove the spacers behind the coil and push it back like from the factory. Now the coil is no way centered on the magnet like the video all but demands. Jody said it doesn't matter were you mount the coil because their rare earth magnets are so much more powerful. I told him they need an upgraded video explaining all these new developments and insights. He agreed, but this issue is low priority........of course it is!

That little cresent shaped air deflector behind the FW keeps falling out so I took a dab of silacone caulk and glued it in place semi permanently. After bolting on the recoil starter I could not turn the motor more than 30 degrees. What else can go wrong? Seems like the fins on the FW are contacting the 3 nuts that anchor the starter. Easy fix with a Dremel Tool and a cutoff disc. Simply grind the nuts down at an angle from the center of the bolt hole down to the lip around the central opening in the housing. I finally finished so I came in to write this before I forgot about this bad dream. Hopefully sharing my experience will save you the frustration I indured. BTW.........they say the stock carb will not work with spacers behind the fan shroud. Mine cleared just fine. If yours doesn't, you don't need a spacer, just rotate the fuel inlet tube to clear. Clamp the tube in a vise and twist the carb around by hand. Just one more discrepancy you'll need to deal with. Who ya gonna believe?
Sounds like you had a field day getting that flywheel on. Is the coil over the edge of the magnet or is it still fully over the magnet?
When I put the alloy FW on my 196, I just put it on and bolted it down. The thing ran like a champ.

Does your FW have advance built into it? That was one of the appealing aspects of the lighter FW, 8 degree advance, no need for a chopped down key.
I'm not a fan of offset keys because of the weak point in the middle, although I realize their need. When I spoke to Jody he said he, and many others, do not even use a key. They find TDC and with a degree wheel set whatever advance they want. After you toruqe the nut down on that tapered shaft it isn't going to move at all. There's nothing dragging on the FW to make it want to slip. Made sense to me.

My 79cc FW has 4degrees advance giving me a total of 32 degrees. I think the larger engines have more ??
And Gordy, the iron core of my coil is riding on the inside edge of the magnet, no longer in the center. The goal is to make the housing fit and not so much about it's location in relation to the magnet. Jody said the magnet is so strong it would trigger the coil if it were on the edge of the FW. LOL
My stock iron FW weighs 4.52 lbs and the aluminum billet one weighs 3.15 lbs . I was thinking / hoping it to be less. Maybe making it much lighter would screw up the balance of the engine ??
I doubt it would throw off the balance much. The flywheel on these more or less just balances either side of the crank case to put a little less stress on the main bearing in the block, the internal balance has more to do with the counterweight on the crankshaft. They make 2.5lbs flywheels for the 212, I'm a little surprised the flywheel for the smaller engine isn't that light.