Centrifugal clutch placement

[wrenching4fun]

Has anyone tried putting the clutch on the output side of a jackshaft instead of the engine shaft? I realize the RPMs will be lower, but that means the clutch will engage closer to the engine's power band. Would appreciate hearing from anyone who's tried this.

 

[Venice Motor Bikes]

I'm sure it will work.. but finding the best gearing to work with the clutch & the style of riding you're planning to do might be difficult.

I've ridden minibikes with a high RPM engagement on the clutch, & it really sux when the engine is always screaming for it's life just to start moving. (it's also really hard on the clutch)!

What kind of engine & bike are you thinking of??

 

[zean]

Hi wrenching4fun. That's a good question because it reminded me of my EZ Motorbike Co. Q-matic motorized bicycle transmission. The builder put the maxtorque clutch on the output shaft of his jackshaft transmission because the engine will spin up faster with less weight on the crankshaft. He also said that the clutch vibrates less when placed on the output shaft. My Q-matic has a reduction ratio of 2.7 : 1. The clutch engages at 1000rpm therefore, when the engine turns at 2700rpm the clutch will spin at 1000rpm and will engage. The reduction ratio within the transmiission is easy to change from about 2.3 : 1 down to 3.5 : 1 with a change of the crankshaft pulley depending upon the size and maximum rpm of the engine you're fitting the transmission to. I have this transmission on Hausheng 49cc and HF 79cc 4 stroke engines and it works very well for many years.

 

[PeteJ]

Zean do you have any pics or more info on the tranny you are using on the 79cc.
Working on a tranny for my 79 now and sure could use some info. Thanks PeteJ

 

[curtisfox]

I found this info, also did you know you can get different spring for the clutches, they will increase the rpms before engagement............Curt

Google Search

www.google.com

 

[PeteJ]

Oh I remember it now and it is one nice set up but just to much money for me. Thanks though

 

[Sidewinder Jerry]

Here's an idea of what you're working with. My RS35 max torque rpm is at 5000. The recommended idle is at 3000 rpm. The clutch engagement is at 4000 rpm. The reduction gearbox is 18.75:1. If I moved the clutch from the primary to the secondary it wound need to engage at 213.33... rpm. The engine would still be turning 4000 rpm when the clutch on the secondary engaged. Many believe by lowering rpm engagement there will be less wear on the clutch thus resulting in the clutch lasting longer.

My clutch is 13 years old with around 5000 hours of use on it. The reason it's lasted so long is I use a tachometer to shift by and I have the widest reduction range in forum history 66.79-16.25\1. If I drop below 6000 rpm at full throttle I down shift. If I'm going above 7000 rpm (max hp rpm) at full throttle I up shift. This way I'm never overloading my clutch.