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Slipper Clutch – A Nest of Clogs?

bikeman

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Slipper Clutch – A Nest of Clogs? | Motorcycle News Resources | Industry, Manufacturers, Sport, Everyday, Track, Community
No, not a group of slippers but a ‘back-torque limiting’ clutch mechanism. You may have heard the term used regularly when discussing the technical details of a modern four-stroke racing motorcycle. It seems that almost every race machine in the two-wheeled racing world has a version of these specialty clutches. Even many modern street-going race-replica motorcycles are adopting them due to their rather successful use at the highest – and toughest – levels of racing. So, what is it?
Simply put, it is a clutch assembly which allows the clutch to ‘slip’ in order to eliminate dangerous engine braking when decelerating into corners. If the rear tire is driving the engine – instead of the other way around – it can be forced to ‘chatter’ or lock-up completely as the compression in the engine fights against the force pushed into it by the rear wheel. If that were to happen while racing a powerful four-stroke motorcycle, a nasty crash often results. To deal with the problem, the slipper clutch will allow the drive and driven clutch plates to disengage momentarily to stop any rear-wheel instability as the rider slows down quickly. It allows the rear wheel to spin, preventing it from having to work against engine compression. In practice, this ‘slip’ happens at very high speed and is not easy to see in action, but it is easy to feel if you are piloting the bike yourself. It is also possible to ‘tune’ a slipper clutch by adjusting how much force it takes to disengage the clutch plates.

In addition to better rear-wheel characteristics when slowing down dramatically, the slipper clutch will also assist the motorcycle’s suspension. In a situation where the rear wheel is not performing smoothly, the rear suspension is also being jarred up and down. That causes the motorcycle to become unstable – another good way to crash. A slipper clutch removes this from the equation and the racer will have a much smoother corner entry, thus a faster lap and a better chance to win!

So, the next time you hear someone talking about a slipper clutch, you will know exactly what it is and how it works – and you won’t imagine a pile of house shoes.
Slipper Clutch – A Nest of Clogs? | Motorcycle News Resources | Industry, Manufacturers, Sport, Everyday, Track, Community
 
So, the question is, "Is there a slipper clutch mod available for the FZ6?"
Prolly if the R6 has a slipper we might have one for our fz6. I believe but am not sure that the fz6 is the same engine with different cam and comp. mapping.
I would imagine the same clutch assembly would work.
That is one mod I'd like to have since I've had wheel slip during compression braking a number of times. Maybe I can come up with and answer searching Ronayers.com Fiche Desktop


Thanks
 
Ok, spent the past hour or so looking extensively at the microfiches and part numbers of the '06-08 R6, R6S, and the FZ-6. Here's what I came up with. Some of it is common knowledge.

The '06+ R6 is a totally different engine from the FZ6 and R6. The tranny is different, the crankcase is different, and it has a slipper clutch. It also has inverted forks and basically is a totally different bike from the R6 and the FZ6.

The R6S of any year does NOT have a slipper clutch, nor does the 04-05 R6.

The 04-05R6 and '06 + R6S crankcase dimensions are identicle to the FZ6. The tranny uses the same shift forks (same part #), but different gears. You could put a R6 tranny in a FZ6 if you wanted to.. but it'd be silly and pointless since the rpm bands are different due to different cams, cylinders, and intake system. Interestingly both bikes use the exact same pistons and crankshaft (same part #) It's kinda scary though how simliar the engines are. You could probably turn it into a R6 engine for the low price of about $4k in OEM parts if you where nuts.
 
Ok, spent the past hour or so looking extensively at the microfiches and part numbers of the '06-08 R6, R6S, and the FZ-6. Here's what I came up with. Some of it is common knowledge.

The '06+ R6 is a totally different engine from the FZ6 and R6. The tranny is different, the crankcase is different, and it has a slipper clutch. It also has inverted forks and basically is a totally different bike from the R6 and the FZ6.

The R6S of any year does NOT have a slipper clutch, nor does the 04-05 R6.

The 04-05R6 and '06 + R6S crankcase dimensions are identicle to the FZ6. The tranny uses the same shift forks (same part #), but different gears. You could put a R6 tranny in a FZ6 if you wanted to.. but it'd be silly and pointless since the rpm bands are different due to different cams, cylinders, and intake system. Interestingly both bikes use the exact same pistons and crankshaft (same part #) It's kinda scary though how simliar the engines are. You could probably turn it into a R6 engine for the low price of about $4k in OEM parts if you where nuts.
What about swapping the 6th gear cogs for the R6 onto ours? Would that make it a taller gear. I want to be able to cruise along at 70-80mph at a lower rpm. I don't need all the extra power that's still available to me in 6th, just would like to save a bit of petrol on the morning motorway commute.
 
What about swapping the 6th gear cogs for the R6 onto ours?
I don't think it'd work b/c the engagement points would be different on the shift drum, (not even close to the same as the FZ's). You'd have to do all or nothing I think.
 
Slipper clutches are quite common with twin cylinder designs.... the big pistons and high compression create a much higher rate of wheel hop from dumping the clutch without matching engine revs. Many cruiser designs have them.... my 2001 VZ800C had one, and that was based on the Suzuki Intruder which was first sold to the public in the mid 1980's.

They are also called 'back torque limiters', and 'Sprague clutches'.... pretty simple in design. There are a series of eccentrics which spread the clutch plates when the rear wheel is travelling faster than the transmission output shaft. No more wheel hop.

They sure do make it a PITA to bump start a bike, though.
 
Ok, spent the past hour or so looking extensively at the microfiches and part numbers of the '06-08 R6, R6S, and the FZ-6. Here's what I came up with. Some of it is common knowledge.

The '06+ R6 is a totally different engine from the FZ6 and R6. The tranny is different, the crankcase is different, and it has a slipper clutch. It also has inverted forks and basically is a totally different bike from the R6 and the FZ6.

The R6S of any year does NOT have a slipper clutch, nor does the 04-05 R6.

The 04-05R6 and '06 + R6S crankcase dimensions are identicle to the FZ6. The tranny uses the same shift forks (same part #), but different gears. You could put a R6 tranny in a FZ6 if you wanted to.. but it'd be silly and pointless since the rpm bands are different due to different cams, cylinders, and intake system. Interestingly both bikes use the exact same pistons and crankshaft (same part #) It's kinda scary though how simliar the engines are. You could probably turn it into a R6 engine for the low price of about $4k in OEM parts if you where nuts.

It looks like there might be some compatibility between the R6 and the FZ6.

This is a slipper clutch assembly from KC-Engineering Shop für Hightech-Motorradzubehör !

Yamaha YZF 600 R6 Bj.’99-’05, FZ6 Bj.’04-’08 S2

Since so many parts are internally compatible between the R6 and FZ6 the differences may be more the external parts since the frame and engine have an integral relationship.

I might get a much needed slipper clutch after all! :BLAA:
 
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