Yamaha Grizzly ATV Forum

brokengriz · Quote #1 03-19-2010, 08:22 PM

i was just wondering how the wet clutch works on the griz 700 works? i just learned that running oil with friction inhibiters etc... will make your wet clutch slip, does anybody have a diagram or can expain what and how this works

Mad Mike · Quote #2 03-20-2010, 07:14 AM

I have mine all apart I will get some pics up this afternoon.

brokengriz · Quote #3 03-20-2010, 12:17 PM

alright thanks i app it

eric · 01:05 PM

I believe there are five shoes that sling out when throttle is applied due to centrifugal force (clutch is directly connected to crankshaft). These shoes are lubricated by engine oil.

These shoes sling out and make contact against a drum, just like a rear brake shoe set up.

Primary clutch is mounted on a shaft that is connected to the drum. Belt connects primary clutch to secondary clutch which drives transmission.

So here it is: Centrifugal clutch is connected to the crankshaft, shoes in centrifugal clutch sling out making contact with a drum when throttle is applied, primary clutch is mounted on shaft that is connected to drum that houses centrifugal clutch that is being driven by shoes which is being driven by crankshaft which is being controlled by throttle.

Grizzly4fun · Quote #5 03-20-2010, 04:10 PM

Welcome to GC!

Yep, and there are different springs that restrict when the shoes contact the inside of the drum. It changes the necessary RPM required (higher) to engage the wet clutch. When engaged, the primary sheave turns at the same speed as the crankshaft. Gearing is achieved with the interaction of the primary and secondary sheaves and the belt around them both. Shims, different roller weights(heavier vs lighter), and machining of the primary sheave (allow increased distance the roller weights can travel) all affect the rate(how fast or slow) and amount of advancement of the belt toward the outside of the primary sheave which will turn the transmission via the secondary sheave faster. You can get different springs for the secondary sheave that can minimize belt slipping and can restrict the rate of advancement of the belt toward the outside of the primary sheave.
Good luck

warj1990 · Quote #6 03-20-2010, 07:22 PM

I want to know how much force the wet clutch can stand before it slips.

As an example last year I was in a pulling contest. towards the end the rpm was high and the wheels were not turning, I let off the throttle and seen the wheels turn just a little when the clutch belt droped into a lower ratio.

So I am 90% sure the wet clutch did slip.

P.S. a Can-AM won the event - not so much because of power- but no wet clutch, just a center one way bearing. (I researched this after the event)

loudelectronics · Quote #7 03-20-2010, 07:38 PM

Quote:

Originally Posted by warj1990

I want to know how much force the wet clutch can stand before it slips.

As an example last year I was in a pulling contest. towards the end the rpm was high and the wheels were not turning, I let off the throttle and seen the wheels turn just a little when the clutch belt droped into a lower ratio.

So I am 90% sure the wet clutch did slip.

P.S. a Can-AM won the event - not so much because of power- but no wet clutch, just a center one way bearing. (I researched this after the event)

The can am did not win because of the lack of wet clutch. In the case of the can am, the belt is acting as the wet clutch and it will be what slips when he powers out.

The wet clutch protects your belt. It is a wearable item but can take lots of abuse as long as you use the right type of oil.

Grizzly4fun · Quote #8 03-21-2010, 03:23 AM

Are you sure you're belt wasn't slipping under the load? Heavier secondary sheave spring might help if so. Are the sheave surfaces glazed over?
Good luck!

plumbob98 · Quote #9 03-21-2010, 10:46 AM

Just out of curiosity, why is there a wet clutch in the engine? Why isn't our system set up like a snowmobile's where they don't use a wet clutch and the output shaft is directly connected to the primary sheave? It just seems like an extra part that's not really necessary. Can someone please explain this, because I find this very interesting and glad someone brought it up!!! Thanks in advance!!!!-----plumbob

warj1990 · Quote #10 03-21-2010, 09:47 PM

It may have been the belt slip, always assumed it was the wetclutch.

When the motor is running 5500 rpm and the wheels are not turning - something is slipping, no the motor did not run out of power - something else gave up.

Mad Mike · 07:20 AM

i can`t get pics to upload have to figure out y.

thomasakehoe · Quote #12 03-22-2010, 07:49 AM

without the wet clutch if the engines crank was just connected to the primary sheave then it would be slipping the belt when you were idling, otherwise you would need to have an automatic transmission similar to a cars where you have a torque converter so that when you come to a stop or at idle it disconnects the engines turning force from the rest of the drivetrain. I was thinking about why they used a wet clutch too on my 600 until I took it all apart and then I saw the mechanics behind it. Seems like a pretty good heavy duty system as long as it is serviced and not abused beyond its limits.

faster3 · Quote #13 03-22-2010, 09:51 PM

They are right about using correct oil. I've got two 700's just now replacing wet clutch in # 2. It's not the machines fault in any way, and won't happen again now that I understand how things work.