slipper clutch not always slipping??

[angler]

Not sure where this should go - here, tech, riding technique.  Feel free to move it.

I have an 05 S2R800.  Twice my rear end has stepped out on a hard downshift like the slipper isn't working.  First time was last summer in the rain in an oily intersection.  I chalked it up to slippery surfaces.  Bike and tires were warm.

This morning I took off for a work meeting.  My bike was cold and my tires were cold.  I turned off my street and accelerated fairly hard up to 35 mph, but I had to slow quickly to avoid a crazy pedestrian trying to catch a bus.  I downshifted fairly hard and the rear really stepped out. The road surface was dry and I didn't see any oil, gravel, or leaves.  Has anybody else experienced this with a slipper clutch bike?

[Slide Panda]

As noted, cold tires and a cool morning. Those conditions can reduce traction by a good bit. Also, the clutch on the S2R800 isn't a true slipper it's a modified Adler Power-Torque Converter (say that 3 times fast) clutch, just FYI and I'm not sure it'll let out 100%. Either way, both situation you describe had reduced traction -  you just pushed the edges it seems.

Slippers are nice, but don't rely on them too much, lest you step out the rear... oh wait...

- Off topic - you going out to Moto Fest Sunday?

[EvilSteve]

I had that happen on my S2R once when I was downshifting way too quickly getting of a parkway. I can tell you right now that it's way more noticeable on a bike that doesn't come with the APTC clutch.

[angler]

- Off topic - you going out to Moto Fest Sunday?

Nope.  I'll be in the cage headed to a week on the Outerbanks for a wedding.  Wish I could make both, but the beach beckons......

Back on topic - your response is what I figured.  I didn't think I downshifted that hard, but given the cold tires and cool asphalt, it makes sense.  I just wanted to make sure it wasn't an indication of something wrong.

I have had many non-slipper dirt bikes and downshifts are something you always pay attention to.......

[orenjimonster]

did you down shift too fast for the slipper to slip?
i dont really know how fast the slipper clutch works.. anyone care to educate me? 

[angler]

did you down shift too fast for the slipper to slip?
i dont really know how fast the slipper clutch works.. anyone care to educate me?  

Apparently. However the slipper works, my tire slipped because the tire was cold (and perhaps the oil too cold) allowing the tire to lose traction before the slipper could slip.  I'll let someone with more smarts than me explain how the slipper works.....

[Slide Panda]

They work fast, effectively immediately. But, the effect is not absolute with that modified ATPC cluch - you cannot bang it into 1st at 60 and not have a bad day.  It reduces, but not eliminates the need to rev match, or slip in your clutch when down shifting. I could be wrong, but as I understand it that clutch set up will slip significantly, but not 100% like a proper slipper could be set to. Even then, most slipper clutches aren't set up to 100% disengage the clutch.

[kingbaby]

Very well said.

Two completely different animals. Yet, all slippers are NOT created equal either.

My advice to people has always been, Unless you are a very skilled rider & know what to do when you stuff your bike into a corner just after you down shifted 2 gears & dumped the clutch...don't even think about it.

Working the clutch, throttle & brakes is becoming a lost art. Thanks to ABS, slippers & traction control on stock bikes that any high school kid can go buy. Manufacturers might as well add 2 more F'n wheels.

Aaaaand off my soap box I go.   

[Slide Panda]

My advice to people has always been, Unless you are a very skilled rider & know what to do when you stuff your bike into a corner just after you down shifted 2 gears & dumped the clutch...don't even think about it.

Though that little maneuver is much easier with a slipper, even the ATPC. I pulled that move on my brand new to me 900, like I would have done on my 620 (dropping 2 gears out of fast straight for a sweeping carry on right, and dumping the clutch) and near shat myself. That little move would have been fine due to the ATPC, was *NOT* cool with the stock clutch of the 900.  There was protestation from the bike, tire chirping and swearing... As a result I think I've become a better rider, since I've learned more 'proper' clutch and throttle control.

(and on to the deserted soap box)
We should all remember that all that tech is insurance for, not a replacement of proper technique

[caperix]

The way the APTC is designed, it will not slip at all if power is being applied, it will only work when coasting.

[orenjimonster]

I guess the best way is to always rev match.
good thing I don't have a problem with that since I like to do it in my car.. and heel-toe as well 

[DucMouse the Mighty]

My advice to people has always been, Unless you are a very skilled rider & know what to do when you stuff your bike into a corner just after you down shifted 2 gears & dumped the clutch...don't even think about it.

Working the clutch, throttle & brakes is becoming a lost art. Thanks to ABS, slippers & traction control on stock bikes that any high school kid can go buy. Manufacturers might as well add 2 more F'n wheels.

Aaaaand off my soap box I go.   

the best advice i have ever gotten...

why spend the money 

sorry for the threadjack