Slipping clutch

[andrecht]

About 5 hours into my new build, my clutch started slipping.
Im running a 9HP Honda clone with a GK9000S centrifugal clutch.
Drive 10 tooth to a intermediate 47, Then a 13 to 32 final.
22" rear wheels.
The GK9000S Clutch according to the suppliers rated at 12HP.
When the clutch is cold, it engages very well, as soon as it heats up it slips....
The question:
Can someone suggest a better lining type, assuming the lining is substandard..?
Will a 9hp engine with a factory fitted wet clutch and reduction box be a better option?

 

[gvfc2]

one thing where did you get one of those clutches? they not anywhere on the internet.

just try a different brand clutch. might solve your problem.

the gearing looks good. at 11.56:1 so thats not the problem. assuming my math is right.

someone else with more experience will chime in

 

[landuse]

You might find that when the clutch heats up, the lining glazes over a bit, and causes the clutch not to grip properly. What you could do is take the clutch off, and then use some sandpaper to take the glazing off the inside of the clutch bell, as well on the clutch lining. The inside of the bell might be glazed over too much.

Wet clutched do work well, the only problem is that they cost a bit here in South Africa. I sold one a little while ago for R700. It was second hand. I think new ones go for about R1500 nowadays.

Your gearing works out to be about 11.5:1, so I don't think it is incorrect gearing causing your clutch to slip. I have never heard of that make of clutch though, so I can't really comment on it.

 

[andrecht]

Got the clutch form a company in Wynberg in Johannesburg. They manufacture ride-on mowers.
http://www.rivim.co.za/

I think i should contact a Break lining or friction specialist company to advise... 3/4" clutches are available, but 1" i had to have made up..

 

[landuse]

Got the clutch form a company in Wynberg in Johannesburg. They manufacture ride-on mowers.
http://www.rivim.co.za/

I think i should contact a Break lining or friction specialist company to advise... 3/4" clutches are available, but 1" i had to have made up..

If 1" becomes a problem, you could always machine your crank down to 3/4

 

[andrecht]

There is noway I'm machining a brand new Engine shaft to suit a clutch??!!
Id rather adapt the cheaper clutch to suit the engine!!

 

[landuse]

There is noway I'm machining a brand new Engine shaft to suit a clutch??!!
Id rather adapt the cheaper clutch to suit the engine!!

It is done all the time, and if you are going to use that engine permanantly on the kart, it is going to be a cheaper and more cost effective option in the long run. No damage is done to the engine itself

Just something to think about

 

[andrecht]

I was thinking of selling the engine and buying a motor with a wet clutch on ti... do you get wet clutches separate?

 

[landuse]

I was thinking of selling the engine and buying a motor with a wet clutch on ti... do you get wet clutches separate?

I am sure you should be able to. You could ask at places like Adendorfs

 

[andrecht]

You are kidding me!!
Adendorf as in tooltime.co.za ??

 

[landuse]

You are kidding me!!
Adendorf as in tooltime.co.za ??

Yup, thats it. I know the one here in town sells engines, so you might find one there. I did a quick look on their site, but didn't find anything offhand. I will see where else I can find one for you.

You can also try honda small engine dealerships.

 

[andrecht]

Perhaps one of these engines is an option?

http://www.tonaro.co.za/product/wet-clutch-7inch-rear-wheels/

Or else they can sell me just the box with clutch?

 

[andrecht]

Removed the bell housing and inspected the clutch..
There is no sign of "glazing" on the shoes or the housing....
Is the clutch just not rated for the HP?

 

[landuse]

Removed the bell housing and inspected the clutch..
There is no sign of "glazing" on the shoes or the housing....
Is the clutch just not rated for the HP?

Many sellers mis-represent their products, so it could not be up to scratch

 

[andrecht]

Simple solution for my problem...

Kinetic friction is the force between two objects that are moving relative to each other.

By increasing the mass of one object i increase the friction between the two objects....

I simply riveted additional weights to the inside of the clutch arms and.......... It works!!

 

[landuse]

Yes!! At least you don't have to get the reduction box now

 

[OzFab]

You can't argue with that, awesome

 

[Doc Sprocket]

Done in the true spirit of DIY. Way to go!