Centrifugal Clutch

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silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Does anyone know if there is a 2-cycle kit that uses a Centrifugal Clutch instead of the normal handle bar clutch system? Thanks!
I have one I got from BoyGoFast. I've only put a hundred miles on it and am now closed down for the winter for any riding. No trouble so far and I like it. It is hard to explain, but you still have a manual clutch which I use for when I pull start. You can also peddle along and let out the clutch to manual start, rev it a bit and the automatic clutch grabs hold and away you go. Coming to a stop you have no need to use the clutch at all. Nice.
SB
 

Nashville Kat

Well-Known Member
Apr 20, 2009
1,501
55
48
Jacksonville, Florida
Did you have to go to wider cranks, silverbear? Don't the centrifical clutches add an inch or so to width? I didn't know you could still pedal start.

Had a centrifical clutch on my Rupp minibike 40 years ago. 2 1/2 horses of Briggs and Stratton 4 stroke power! Put a Mac 49 2 stroke cart motor on and it had a better top end, but took forever to get there!
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Did you have to go to wider cranks, silverbear? Don't the centrifical clutches add an inch or so to width? I didn't know you could still pedal start.

Had a centrifical clutch on my Rupp minibike 40 years ago. 2 1/2 horses of Briggs and Stratton 4 stroke power! Put a Mac 49 2 stroke cart motor on and it had a better top end, but took forever to get there!
It does add width both from the pull start assembly and from the clutch. My bike is 63 Schwinn so has a one piece crank. As far as I know the extra wide cranks are three piece so require an adapter kit. Between the crank and the adapter it starts getting expensive. It was simpler for me to use a cranks with a shorter arm. Some exercise bikes have shorter arms as do 20" bikes. You can also just by the arm from bikeworldusa and I think Niagra also has them. Whenever I go to the landfill I look for old bicycles and a 20" one will often yield an appropriate crank. If rusty, they can be a bugger to get off the donor bike. So, you can go shorter or wider. I have a wide crank still in the box and have heard people complain about the pedals feeling awkward. On the other hand a shorter crank gives you less leverage and on a heavy old single speed that can make pedaling more of a chore. You gain one thing, you lose another. Yes, you can still pedal start by getting yourself going and letting out the clutch. Once started you give it some gas and the automatic clutch engages... then off you go. I personally like it.
SB
 

VermontCruizer

New Member
Jun 17, 2009
32
0
0
Vermont
Thanks Silverbear! I am looking at those kits from BGF and I think I will upgrade to the 2 clutch/2 start system in the spring. On another issue, do you do anything special to put your "hog" away for the winter? I am going to run the tank dry, but other than that should I do anything else? Thanks.
 

silverbear

The Boy Who Never Grew Up
Jul 9, 2009
8,325
670
113
northeastern Minnesota
Thanks Silverbear! I am looking at those kits from BGF and I think I will upgrade to the 2 clutch/2 start system in the spring. On another issue, do you do anything special to put your "hog" away for the winter? I am going to run the tank dry, but other than that should I do anything else? Thanks.
You're welcome. I use Opti-2 gas mix which has a built in gas preservative in it, so don't worry about draining the tank. Years back when I had a resort and a number of outboard motors to put away for the winter I would run the carb dry and put a preservative i (Sta-bil) in the gas tanks and never had a problem. I think it also might make a difference for how long you anticipate not running the bike. If it's just a few months, beyond what I've mentioned above I wouldn't worry about it.
SB
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
63
up north now
Actually, if you live where there is much humidity, or the bike will undergo several temp. changes (like outside) you'll want to full the tank and add Sta-Bil. The reason for the full tank is to prevent condensation and/or rust inside the tank.

Just fill it, run it for a minute to get the Sta-Bil in the carb, and shut it off, and cover it up for the winter.
 
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