7moore7

Long story:
I bought an extra clutch plate and had it powdercoated yellers. Somewhere along the lines communication go lost and they sandblasted the whole damn thing before coating the one side. Usually they leave machined surfaces alone so I didn't expect this problem. I'm making a clear section in the cover of my motor and you'll be able to see this.

Short story:
Does the inner surface of the pressure plate need to be smooth for any reason or was it just machined to make it level or something? Looks like it's important to be smooth, and I would like a confirmation of that. Next to is is the stock one that I just pulled.



Side story:
Don't have your friends drop off powdercoating for you. I would have fully made sure to make it clear to not touch that edge, but something this obvious to me skipped two or maybe three people's brains. So if you're painting the inside of your motorcycle yellow, buy a powdercoating oven or risk wasting a good $25 on what now looks like a single colored rim for a very small truck or large RC car.

nuhawk

I think this a problem. Clutches are made up plates that grippers and slippers. Unfortunately unless you have access to a lathe this is going to be a very difficult clean up excercise. My .02 good luck.

You still good for the races in Feb?

superbeater

I don't know for sure, but I disagree. I know we used to sand down automotive pressure plates and flywheels that had glazed. Just like you might bead blast brake discs that had pad material built up on them. I'm guessing that the shiny clutch looks as it does because it has been used. I'd bet a new one doesn't look so polished. The piece that was powder coated is simply a pressure plate that sqeezes all the clutch plates together. It does not have to be super polished to work. Again, I'm guessing, but I think it is still fine. Might not be quite as smooth for a while but it isn't junk just because it was blasted.

7moore7

This is my first time into the clutch, so I didn't know. I suspected what Doug was saying... it seemed too smooth to be unintentional, and seemed to need to be frictionless.

But I hadn't thought about it in the same sense that it may wear itself smooth like brakes. Perhaps I may only lose out on a very little bit of performance b/c it is only a one surface on what appears to be a whole slew of them. I'm assuming all of these are friction plates, and very quick online research shows that this is a part of the wet clutch system...

I'm hoping that Tweety does a search on his own name on occasion and so may check this thread out

Thanks for the replies... I'm going to sleep on this one to give me some time to research it a bit.

thetophatflash

Where is the powder coat going if it does wear smooth because of plate movement? How coarse will the small particles of debris be?

7moore7

Well the PC shouldn't go anywhere. It's on the surface that isn't being used... the PC guys just bead blasted the whole thing and I'm trying to figure out if the surface that used to be real shiny is now an issue?

All that little PC stuff on the back will be cleaned up by yours truly before I install the bearings and assemble the plate/

7moore7

It does contact, although do you think your statement hold true with a wet clutch?

Haha, most of my problems have been getting my motorcycle back to stock... if I solve this I'll have a stock working clutch. Whereas if Mikstr solves something he as a more advanced pressure regulation system in his crankcase!

E.Marquez

That surface is designed as a machined and smooth surface, even on a brand new part.

The Media blasting brings two issues to the plate.
It may have made the surface uneven, which as noted can cause chatter, grabbing, overheating and quick destruction of the clutch pack.

And
The very rough surface will have a much different friction point on the drive disk. One other unintended consequence is, the media blasted surface will no retain much more oil than the machined and polished surface would..

Lastly, with the removal of surface area on that blasted one, and the further wear that will quickly take place as the “highs” on that surface wear in use.. the clamp distance for the clutch assemble will be less…. Enough to matter ? No way to guess.

All that said.. It the cost of a gasket.. I’d likely give it a shot.. if it does not chatter, nor slip, and the friction points are not so far off that smooth engagements and release are not overly effected.. I would not be afraid to try it out.. But very carefully and stay very in tune with how it reacts and wears in over a few hundred miles.
Expect the oil to get very dirty quickly on first use, as the pressure plate surface wears in.

Tweety

Well, I'm no clutch expert... But yeah, like others have said, it's machined smooth on a new part...

As it is, I expect the disengagement or engagement of the clutch to be rather abrupt and grippy and the result would probably be that it's completely impossible to "slip the clutch", making it fairly digital, and a chore to use...

That is, if it works like this and doesn't chatter and ****** or other wierd behaviour...

But, like E.Marquez says, I'd say it's worth trying it out, If you take it easy and "feel" it, at worst you will end up replacing it for excessive wear or bad feel, nothing else will really be damaged...

7moore7

Alright, seems like everyone's train of thought is the same of mine. Unless this is all a ploy to get me to loop my bike and destroy a superhawk. In which case I'll be sure to take pictures...

I may also see if I can find a way to sand it smooth if that doesn't work... I'm thinking a drill and a table with a 4 in hole in it may play a part

Wolverine

Ok, for ***** and giggles lets say it is supposed to be smooth. As that surface gets worn in and smoothed over, would it not leave a bunch of material to flow around in the oil(until it gets filtered)? For that reason alone I would vote to the side of getting it machined smooth. Small price to pay now to prevent possible larger problem later??? Just a thought.

After viewing the parts fiche, it looks like a friction material plate goes against that piece. Would it not chew that sucker up pretty quick?

lazn

Unless I am confused, that is only one of many gripping surfaces as it is a clutch pack and not a single flywheel clutch like a car. So my guess is you will lose some of the feel, but not all as the other disks in the clutch pack will provide the smooth surfaces. (that one surface will grip too soon, the others will work as normal)

7moore7

Thanks for the feedback everyone... it all was very helpful and I took it all into consideration

Lazn, your are correct- there's a whole slew of plates. I gently wet sanded off some of the burrs, aware that too much sanding would cause an uneven surface (in other words, I didn't sand it much).

I think we're going to try this... at least it'll get the question answered. It looks too cool in there

As far as I can tell, it may grip earlier or even immediately: effectively removing the slipping of one of the sides of one of the plates. I'll keep a careful eye on the oil and go real easy for a little bit on it. It doesn't seem like a precision mated part from the nature of how the 5 clutch springs seem to be the only thing pressing the plates together. Worst case scenario, I'm not destroying a $15,000 Hyabusa or anything.

Here's a small pic of the reason why I'm keeping with this :

nuhawk

It's a great look. As the paint wears off the plate it ends up in the oil - yeah - all the oil.

nuhawk

If the coating was ceramic I'd be less worried but the fact that it's paint concerns me. That coupled with the fact that the oil in the tranny is shared with the lubricant for the valve train and cylinders.

Tweety

Agreed... And oil is fairly well known for lifting paint, even if it's powder coating it's not "safe"... Especially since it has an "open edge" where the oil gets under the painted/coated surface... Add some heat, and you get the perfect mix of things that don't work...

7moore7

You guys forgot that it's spinning pretty fast, so anything loose will be flung into the case.

Way to kill my aesthetic modding buzz Sighhhh....

It's in there now, functioning with no noticeable difference ATM. So as far as initial clutch chatter and sensitive motion concerns it seems that there are none. Again, I'll be keeping a close eye on it to see if any continuous use issues arise.

I really can fix a lot by putting the old plate back on, I just don't want to drain the coolant AGAIN and part of the oil and mess with gaskets and pulling a water pump and re-filling the coolant (which takes a bit of time with the way my lines all run) and all that stuff.

nuhawk

Go down to Wally-World and buy a case of oil filters. Throw them away every two hundred miles. If your lower fairing is fitted around the stock size filter this size will be too long. SuperTech ST7317 is the one that I run. They do usually stock the shorter one as many bikes use this size. The ZX9, CBR, Superhawk, and VTR all use this filter. $1.77 each by the case. Price has prob gone up since my last buy. I bought three cases because I was feeding four bikes.

7moore7

Righto, on another note, we're getting started on another round of shirts

7moore7

Just to update this. I've been riding the clutch for two weeks now and there is no noticeable difference in chatter, grab, sensitivity or even dirty oil. I'll change it this weekend, but seems to be running fine.

This is an issue that may develop itself over time, but none of the immediate effects that we speculated on are showing

Wolverine

patience daniel san