Did a little work in the garage this weekend, I guess I should start a "real" build thread... So far the kit is still looking good but the spark plug boot broke into pieces from just putting the cap on the new plug, lol. Then when trying to unscrew the wire, it just disintegrated wherever I tried to hold it with pliers. So I dug the remainder out with a screwdriver and am on the hunt for an ~2ft section of copper core wire so I can mount the CDI under the engine...
BGF RB80, larger intake port?
- Thread starter maurtis
- Start date
BTW, after doing some looking about, this RB80 looks like it is the same as the Grubee GT5-A, but with an NT carb. I am not certain, but the GT5-A has wider intake studs than "regular" HTs, a port matched intake manifold, and 6MM head studs, as does the RB80.
Bairdco reported having major issues with blowing head gaskets on the GT5-A, so I will keep an eye out.
Bairdco reported having major issues with blowing head gaskets on the GT5-A, so I will keep an eye out.
Just an update on this motor, after about 400 miles she is still running great! I have a Puch head on her now so starting is more difficult since I am still trying to dial in the clutch pressure, but other than that she runs like a top.
This motor really smooths out around 32 MPH, almost buttery smooth. But at 35+ she shakes pretty good. At almost 40 (the max I have hit is 39.8, so close...) she will make your hands go numb.
My bike was down for about a month since I found two hairline cracks in the Cranbrook frame at the seat post and head tube, so I found an older Schwinn frame that I transferred my gear over to. I am thinking the upper RPM vibes did not play well with the Cranny... BUT, I really like the motor mount setup (welded front mount), slightly different ergonomics, etc on the new frame, so it was all for the best.
This motor really smooths out around 32 MPH, almost buttery smooth. But at 35+ she shakes pretty good. At almost 40 (the max I have hit is 39.8, so close...) she will make your hands go numb.
My bike was down for about a month since I found two hairline cracks in the Cranbrook frame at the seat post and head tube, so I found an older Schwinn frame that I transferred my gear over to. I am thinking the upper RPM vibes did not play well with the Cranny... BUT, I really like the motor mount setup (welded front mount), slightly different ergonomics, etc on the new frame, so it was all for the best.
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Good to know that she's running fine. My BGF Z80 lasted 300 miles and the main bearings were growling. I replaced them with new ones and she's back running fine. Maybe they used better bearings in the RB80?? Maybe mine were just junk from the start. Gotta love these little engines.
I recently purchased the same kit from BGF but did not receive instalation instuctions, most of it is pretty simple stuff, but after I installed everything the motor would not free spin, hense my rear wheel is won't spin freely. Is there some sort of clutch assembly that I need to install in order to allow it to spin freely?
http://www.grubeeinc.com/USA/STARFIRE%20%20SKYHAWK%20WEB%20INSTRUCTIONS.htm
http://www.grubeeinc.com/USA/STARFIRE SKYHAWK WEB INSTRUCTIONS.htm
The clutch may be stuck. Remove the clutch arm cover (left side) and strike the bucking bar. The bucking bat should be sticking out of the center of the shaft about 1/4". By striking the bucking bar, and if the clutch is stuck, it should separate the pressure plate from the flywheel. Make sure that the clutch cable is adjusted properly.
If you need to take the clutch apart, there is a link in my signature that has pictures on how to do it.
Ron
