R1 Clutch is Dry

[RobLav]

Question here - how wet does the 06 R1 clutch need to be? My clutch started slipping at NHMS first time out, so now I have it out and apart. Not one drop of oil spilled out of the clutch cover...

My scavenge pump on the dry sump must be doing quite the job.

None of the clutch plates were scored, just obviously very hot. 4 of the clutch disks are under spec, but not one of them wore completely through the friction material. Of course, it smells like everything there got hot.

The springs about to go in it are a lot stiffer than stock. Those and the new clutch plates and disks (am hoping anyway) should fix it. Just concerned now about too much heat in the clutch without much oil flow in there.

Any thoughts?

Thanks,
R

[glenn cooper]

That is a DAMN GOOD QUESTION!
I had not thought about that. I believe that there are a series of spray bars and tubes, that are supplied pressurized oil from the Yamaha oil pump. They spray onto the gear stacks, underside of pistons, and I'm thinking the clutch as well. I'm pretty sure the stock wet pan doesn't have the clutch basket actually in the oil, but obviously you have some type oiling issue...
GC

[HastyHorn]

1. I have run an R-1 with a dry sump system that scavenged at 120% the volumn that the output pump produced. 2. The clutch plates get oiled through the transmission shaft. I don't believe that an over efficient system is the problem.

If your problem is really no oil getting to your clutch I would have some concern that the oil passages leading to the main shaft were somehow plugged which could lead to more serious problems than just clutch failure. However, it is more likely that the slipping clutch started with an improper adjustment. Once the clutch begins to slip there very little to recover besides plate replacement (I've done this several times before I understood the sensitivity of the system).

Is this problem in conjunction with a recent engine re-build? If you have a shop manual look up the oil flow diagram (front of manual) and check passages. Carefully applied air pressure may help discover the source of the problem.


Hasty Horn

[RobLav]

Thanks Hasty / Coop...

I have the Taggart dry sump pump and the billet aluminum Citation sump / engine bay floor...

Having never worked with wet clutches, I'm not sure how wet they are supposed to get. Since the engine sat for over a week since the last run, there is plenty of room for the oil to drain out of the clutch cover area. Upon removal, all the clutch disks and plates had some oil on them, just didn't seem very much to me.

After some research, it seems drag bike guys also have an issue with the R1 clutches. McCoy Motorsports makes a clutch oiler assembly that feeds fresh cooling oil through the cover onto the clutch basket and disks. They feed that from an oil galley plug near the sight glass. I can use the same concept and feed oil through a -10AN tee at the scavenge line after the oil/water heat exchanger through a -3AN line and through the clutch cover. That scavenge line is already routed at the top of the clutch cover on its way to the tank, so it wouldn't really be too much to add.

Since I found that 4 of the clutch disks were out of spec, I'll try installing a new set of clutches and those stiffer EPC springs and see how it holds up. If it fails again, I'll connect up that oil cooling method.

The next engine will be an 07 or 08 Yamaha with the slipper clutch... hopefully it won't place as much stress on the disks and plates. I can't see spending $750 or so on a new slipper clutch for this engine when I can buy a complete newer engine for about twice that.

[glenn cooper]

and got outta bed, put my pink bunny slippers on, stubbed the hell outta my right pinky toe (you owe me, sucka!) on the corner of my bed post, came downstairs, logged on and...
You did recently have the clutch apart, right?
Had you oiled up/soaked the fiber plates prior to assembly?
You mentioned you did not have any/much experience w/ wet clutches, and this certainly coulda been the prob, Rob (Snap! M I Good or WHAT?)

I'm just sayin'...

GC

[ReynardF1000]

On my '03 R1 with a very full wet sump (full above the sight glass), I removed the clutch cover and the chamber was dry. Apparently oil is controlled in the clutch chamber to reduce pumping losses during running.

[George Dean]

A R1 clutch dosent see much oil, even in its stock wet sump configuration, Every R1 clutch I have disassembled has been fairly dry, Things got hot in your clutch because it was slipping, When a clutch is fully engauged no heat is being generated, My guess is the proplem is in the springs you were using. If you were using the stock springs there probably is not enough spring pressure to keep the clutch from slipping and burning. You must remember they designed this engine to haul around a 400 pound bike not a 1000 pound racecar. I always put heavy duty clutch springs in every engine I prepare for racecar use, Put in the new clutch, Heavy duty springs, Make sure your foot dosent rest on the clutch pedal when you have it on your dead pedal and everything will be fine.

George

[RobLav]

Thank you George. Perfect answer.