HS 4G Trans Options

outlawbiker

Member
Mar 15, 2009
282
0
16
Chicago NW Suburbs
Weather is getting warmer and its time to build some bikes again! Only problem is i cant seem to find where i was told which version of the 4G trans to buy, the seller has these options:

20Tx80TFW x 9T/10T
20Tx100TFW x 9T/10T
20Tx100T x 12TFW

from what i can recall, TFW = Toothed Free Wheel? and if so,wasn't there an issue with a specific one of these models years ago? Ive bought from these guys last year and the kit had "2015" all over it, i was thinking it was pre 2014 that one way bearings or free wheels were breaking on these? sucks getting old,cant remember stuff.

anyways,id appreciate some direction on which one to buy,thxs!
 

KCvale

Well-Known Member
Feb 28, 2010
3,967
52
48
Phoenix,AZ
The West coaster supplier for Grubee/Skyhawk is bicycle-engines.com
The is another supplier on the east coast but I can't recall their name.

Good info on 4G's here.
http://grubeeinc.com/4G T Belt Drive Transmission 01.htm

If you want to go fast and pedal on hills go with 80T freewheel, if you want to go quick and not pedal, go with the 100T freewheel.
 
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outlawbiker

Member
Mar 15, 2009
282
0
16
Chicago NW Suburbs
thanks KC,your always a fountain of useful info when i need it

any thoughts on the TFW? specially the 12TFW? after what you said im considering the 100 but which one?

Not sure but is that trying to say the freewheel is on the output sprocket, and the others is on the big toothed pully?

EDIT: I found more info on a thread KC posted on for anyone in the same boat.

4G solid secondary 100T pulley and 12T freewheel output sprocket. (20Tx100T x 12TFW)
4G freewheel secondary 100T pulley with position adjustable solid 9 or 10 tooth output sprocket.(20Tx100TFW x 9T/10T)

I think im going with the freewheel pully one, seems to me like less abuse on those bearings than the sprocket side one where the chain could be "slapping" or if the hub sprocket inst completely concentric cause the chain to pull on it.
 
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