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HF parts line could not verify the auger engine and the water pump engine were indeed the very same engines. For the sake of us all, I went to the trouble of removing the auger engine from my bike to compare the two. Also see attached photos. And keep in mind, the red engine is form the auger and the blue one from the water pump. The centrifigal clutch from the auger is a direct bolt on for the pump engine. I swaped it out. you'll see in the photos. The pump engine with the clutch installed bolts up to the mounting bracket on the bicycle, no problem there. The only differences I see in the two engines are these, the rotor/fly wheel on the blue pump engine is a little different and the kill switch on the pump engine is a single wire rather than a 2 wire like the red auger engne. The rotor on the pump engine sits further back inside the crank case than the auger engine. When the clutch is bolted on the blue engine, the outside edge of it is about flush with the outsdie face of the engine caes/block. On the red auger engine the clutch protrudes out fomr the face of the block by about 1/4". I didn't bother to measure. Again, pay close attention to the photos. Sorry for a few crappy out of focus photos. I had dirty hands and did not want to handle my camera any more than I had to and didn't realize I had bad photos until I down loaded them. Anyway, on the auger engine I've been using, the clutch seems to go only about half way into the clutch drum. That's obvious from the wear on them. When the blue engine is bolted on, the motor will not turn because the mounting screws that holds the engine on to the mounting bracket are to long and get into the rotor. That's as far as I went. But....my personal opinion is use shorter screws and spacers to mount the engine to the mounting bracket and it will work. I don't have screws or spacers readily available or I would have done this to make sure. After going through all this, I might install shorter screws and spacers on my red/auger engine anyway so the clutch will fit further up inside the drum. I don't guess it really maters how far in the drum it goes as long as the total surface area of the clutch shoes are making good contact with the drum.
All this nformation is my own non professional observations and based solely on the friction drive kit from bikemotorparts.com. I think it will work provided that you get proper length mounting screws and spacers. Again, I did not take measurements, but I think screws and spacers between 1/4" - 1/2" shorter than the ones that came with the kit (BMP) will make this thing work. If anyone goes for this, do yourslef a favor.disconnect the plug wire and carefully pull the starter cord and make sure the rotor is not hitting the screws. That would be a costly mistake to start an engine for about 2 seconds and it be ruined !
One more bad thing. According to the parts people, the clutches cost whopping $2.34, but they said 6-8 weeks for delivery. S_Beaudry and I have kind of been working together on this and comparing notes with each other. I think he's in pursuit of finding a clutch localy that will work. One of us will keep you posted ! Hope this help ! If anyone has question, get in touch !
Thanks !
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