4G belt drive freewheel broke, HD replacement?

I'm a bit peeved...

I finally had time to finish up Big Red, my new personal ride since I let Bad Mojo go and customer builds come first so it took a lot of time

She's a 2012 Macargi Pantera with a 3-speed wheel and SBP Jackshafted Chinese 49cc 4-stroke motor with Grubee G4 belt transfer case.





I still have more cosmetic stuff and handlebar accessories to do but I finally got it mechanically done and went for a test ride.

It flew through the 3 gears and he got me to ~35MPH without a single pedal in about 7 seconds with more left in it and *poof* the G4 freewheel broke.
That would be the freewheel bearing inside the big belt pulley, and I doubt I even got 500 yards.

The odd part is it is not a 'hard failure'...
I figure it has to be a haunted G4 or something as it has been a problem child from day one.

Anyway I emailed Bicycle-Engines,com to see if it's covered but I would like to know if anyone else has seen this and Is there a solid replacement for the G4 Freewheel?

I'm Jackshafted so the freewheel is at the source, where the 3-speed hub attaches to the drive train so a Freewheel in the G4 is a useless vulnerable point anyway.

I haven't even pulled the freewheel out of the pulley yet, I am just trying to get a head start and of course show off my new build ;-}

Bicycle-engines will replace it free but I have a Mig welder here, I'm just going to weld the freewheel.

fredgold52 said:

... I just wanted to tell you that's a really nice looking bike. The way you have it set up with a jack-shaft looks very good. My compliments on a great bike.

Click to expand...

Thanks Fred and it's fixed, we just welded the G4 freewheel bearing solid.

Yes, the 3-speed hub has a freewheel so there is NO drag when you drop to idle and coast, the only thing I loose without the G4 freewheel is that belt to the clutch I'd have to pull when it was pedal only which I try to avoid at all costs. Heck, I don't even have to pedal to launch it from a dead stop ;-}

BIG RED is a dragster with just 3 gears, most strong motor shifter bikes in my experience are, the thing about the 4-stroke is once you get to that 'magic speed' of ~35MPH when the wind resistance barrier plays a big part and 2-strokes start to falter the 4-stroke just gets stronger in the proper gear.

I couldn't care less what the top speed is, all that matters to me is feeling confident pulling out onto a major 40-45MPH city street in a hurry and being able to keep pace with that traffic even in stop and go.

I don't particularly like riding that fast in traffic and prefer the mid 30's, but again my experience has taught me the better you can stand out (bright blinking daytime running light) yet blend with traffic flow the safer you are.

BIG RED is a big heavy man sized bike with man sized performance.
I really wanted to put a real shock on the front and a seat post shock to go along with the better seat and more comfortable handlebars I put on but he's gotta go. Frigg'n life bills suck.

It doesn't look finished to my vision but more than finished and I posted it up for sale on my local Craigs for $1050.
Not much profit considering the labor but enough to live and build another day ;-}