I see lots of noodles

[3Phase]

Do you have a machinists dial gauge that you could run it against to see how high/deep the wear marks are?? I would think you could shave a few thousandths without much trouble, but putting in an extra steel could help take up the slack!?

That's a good idea there; feel and appearance are deceptive so I'll dig my gauge out of storage. I made a quick test with a mechanic's pick. The marks scratched easily and the point seemed to make equal-sized pits when pressed into the marked and unmarked aluminum surface.




After investing in new springs, steels, and frictions and talking to one of the mechanics at the dealership yesterday I'll just bite the bullet and buy a new Pressure Plate 2 and be done with it. Apparently there are no dimensions given because the part is considered more of a consumable item that is replaced when a clutch is changed. Replacing a part that has no specified initial dimensions or service wear limit makes me uneasy.

Moving right along: NW Vintage Cycles claims to have a new pressure plate 2, part# 2H7-16325-00-00 for $31.65. That parallels your search, T.C., that found one for $29.50 a few years ago.

Everyone else wants more; I blame Johnny Depp:

Local Yamaha dealer: $52.57
Boats.net: $47.61 + shipping
SpeedSupplies.com: $60.39 + shipping

Yo ho! Yo ho!

On my clutch, the surface is turned, not milled. I am perplexed as to what caused that as well, unless at some point it was run metal to metal, with the friction material completely gone.

The second owner swears he just put in fuel, oil, batteries, and rode it but there are wrench marks on the main clutch hub nut and the washer has been re-crimped. The clutch has been worked on at least once but it had to have been over ten years ago.

Only thing I can think is that it was improperly installed at some point. Those nubs should fit the splines on the pressure plate. If there were a steel there instead of a friction disk, it would have kept the nubs from seating and possibly rattled around when the clutch was disengaged, causing the mirror image witness marks.

I took some more measurements after reading the above.

A steel won't fit onto Pressure Plate 2



There are no misalignment marks on Pressure Plate 2 nibs or the splines on the Clutch Boss Assembly



The splines on the Clutch Boss Assembly and Pressure Plate 2 have no unusual wear




Some additional thoughts about adding an extra steel to a non-worn clutch assembly:

The nibs on Pressure Plate 2 are only 0.080" or 2.032mm







OEM clutch pack exposed spline height is 0.115" or 2.921mm




OEM clutch pack exposed spline height with extra steel is 0.035" or 0.889mm



With an extra steel added to the clutch pack only 0.035" or 2.032mm of the splines on the Clutch Boss Assembly will engage the nibs on Pressure Plate 2. The pressure plate can pop out under load and try to rotate like the gear dogs/slots in the transmission. That would round the ends of the Clutch Boss Assembly splines and Pressure Plate 2 nibs and strike clutch springs and posts. If the pressure plate stayed rotated and the nibs 'hung' on the ends of the splines the clutch would not release.


Okay, that is more than enough clutching, it's time to go pull the oil pan and see what other mischief has been wrought!



Regards,

Scott

[Ivan]

Well, I have found the problem. Your work area is way to neat. I bet you don't spend near enough time searching for wrenches. That in its self will make your clutch give fits, out of sheer envy.

[TopCatGr58]

There are no misalignment marks on Pressure Plate 2 nibs or the splines on the Clutch Boss Assembly

The splines on the Clutch Boss Assembly and Pressure Plate 2 have no unusual wear

Some additional thoughts about adding an extra steel to a non-worn clutch assembly:

The nibs on Pressure Plate 2 are only 0.080" or 2.032mm

With an extra steel added to the clutch pack only 0.035" or 2.032mm of the splines on the Clutch Boss Assembly will engage the nibs on Pressure Plate 2. The pressure plate can pop out under load and try to rotate like the gear dogs/slots in the transmission. That would round the ends of the Clutch Boss Assembly splines and Pressure Plate 2 nibs and strike clutch springs and posts. If the pressure plate stayed rotated and the nibs 'hung' on the ends of the splines the clutch would not release.
Regards,

Scott

Hey Scott,

As per your comments above about no unusual wear marks on the nibs of the pressure plate #2 or clutch boss, that is true. But your worries about the #2 pressure plate spinning and catching on the edge of the clutch boss is unwarranted....BECAUSE the clutch boss and pressure plate #2 are BOLTED together via the 6 clutch bolts and star plate. The entire inner clutch boss/pressure plate assembly is what spins with the steels, and the outer clutch basket is what spins with the frictions, and it's the grip between the 2 that of course sends the power from the engine to the tranny!?

There are no wear marks on the nibs of the pressure plate #2 because those nibs don't rub against anything really, the first steel is a few mm's above it, it's just there as part of the design to allow proper alignment of the clutch boss during assembly, and the boss just slides in and out sliding thru the steel splines when the clutch is released/separated and then back together again! The boss is guided by the very snug holes that the pressure plate #2's spring posts fit into and slide within.

T.C.

[3Phase]

Well, I have found the problem. Your work area is way to neat. I bet you don't spend near enough time searching for wrenches. That in its self will make your clutch give fits, out of sheer envy.

Oh, yeah, r-i-i-i-g-g-h-h-t! That's the calm, clear, eye of a veritable garage tornado you're seeing.


I am, however, ready to kick back and have a cold beer. There are some small bits and pieces of gasket but no metal in the strainer cover[1] or the oil strainer. It looks like the strainer cover has been removed and cleaned before as there are scrub marks in the corners and along the inside edges.








Regards,

Scott

1. I know it's an oil pan; you know it's an oil pan; Yamaha knows it's an oil pan, but I'll play their silly game and call it a strainer cover!

[3Phase]

Hey Scott,
...
the clutch boss and pressure plate #2 are BOLTED together via the 6 clutch bolts and star plate.
...
T.C.

Oh, man! Thank you, T.C.! I have been staring at this thing for too long... way too long! Forget all that speculation stuff!



The marks on Pressure Plate 2 may have been caused by wavy steels and the friction plate moving slightly on the pressure plate on acceleration/deceleration. I looked at all of the old steels with a magnifying glass under a strong light and it looks like the stamping die left waves in some of them and they're not flat.

They steels were cut cleanly enough but it looks like the die was old or loose and allowed the steel to move ever-so-slightly in the die as it was stamped, making a giant wave-washer.

Unfortunately I couldn't get it to show up on camera and I still have no idea where the milling marks came from.

On the bright side, I found no metal bits, chunks, or partial parts in the oil when I removed the strainer cover a little while ago so I'm having a nice bottle of ale to console myself in my sorrow!


Regards,

Scott

[tarzan]

That odd pattern looks an aweful lot like chatter to me.I've seen it a lot while turning parts on a lathe.It does look like it has hard spots in the swirly areas,Maybe.

I just looked at that again.I havent had mine apart,the plate that sits on that surface doesnt spin against that surface does it ?So if that is the case it makes sense
that it wasnt considered a problem to whoever assembled it.It could actually been that way from the factory.As long as it is flat and in spec I bet it is actually ok.

[3Phase]

There are no wear marks on the nibs of the pressure plate #2 because those nibs don't rub against anything really, the first steel is a few mm's above it, it's just there as part of the design to allow proper alignment of the clutch boss during assembly, and the boss just slides in and out sliding thru the steel splines when the clutch is released/separated and then back together again! The boss is guided by the very snug holes that the pressure plate #2's spring posts fit into and slide within.

T.C., I really like the extra steel mod. If I could get the pressure plate resurfaced I could probably use an extra steel. Right now, Pressure Plate 2 and the Clutch Boss Assembly are not worn enough for an extra steel.

I took another look at the spring towers and the clearance inside the boss. The only thing the star plate and the bolts hold is the springs and there is nothing but spring pressure keeping the pressure plate nibs from popping up and onto the boss splines under load.

With the extra steel, only ~0.035" of my boss' splines can engage the pressure plate nibs. It's a little more when the clutch pack is snugged down under the star plate but it's still pretty thin. It's even less! when I use the old, thicker, steels that came with the bike. When the tips of the nibs and splines wear the pressure plate will ride up the boss splines under load and the spring towers will begin to take hits. It may or may not be noticeable when you're riding. I think it was Maximan that came up with the Tech Tip fix for broken pressure plate spring towers.


Clutch at rest in neutral



Clutch under acceleration



Clutch under deceleration



I'm buying another pressure plate but I'm thinking about weighing some pins for balance, then pressing them with some red Locktite into the base of the pressure plate spring towers on the old pressure plate.

That odd pattern looks an aweful lot like chatter to me.I've seen it a lot while turning parts on a lathe.It does look like it has hard spots in the swirly areas,Maybe.

Yes it does look like chatter, along with rippled steels. The steels never move relative to the pressure plate except for a little bit of slack.

I just looked at that again.I havent had mine apart,the plate that sits on that surface doesnt spin against that surface does it ?So if that is the case it makes sense that it wasnt considered a problem to whoever assembled it.It could actually been that way from the factory. As long as it is flat and in spec I bet it is actually ok.

The bottom friction does spin against the pressure plate.

As to in or out of spec: the frictions were useable but a couple of the steels were warped.

The pressure plate has no spec and there is no spec for the Seat Plate, the Clutch Boss Spring Plate, or Clutch Plate 1 on the Clutch Boss Assembly.


Regards,

Scott

[3Phase]

New Pressure Plate 2 2H7-16352-00-00

I ordered a new Pressure Plate 2 from nwvintagecycleparts.com on Monday and it arrived late Wednesday morning.

I called before ordering as some online outlets list items they do not actually have in stock; nwvintagecycleparts will not list a part unless it is actually available and in stock - superb!

The new pressure plate surface is smooth with no vestigial tool marks or hard spots


The new part measured surface thickness is 0.4035" or 10.25mm;
almost the same as the old part surface thickness of 0.400" or 10.16mm


The old shipping tag for a part with a MSRP of $63.57



For now, the clutch is back in the bike with no extra steel plate.


Regards,

Scott

[3Phase]

Follow-up: About Four-and-a-half Years and 70,000 Miles Later!

EARTHQUAKE! yikes, that was fun! 7:37 PM PST.

Moving right along!

Carburetor Slide Springs:

I still haven't found a definitive spec. for the springs. I put the two longer springs in the two middle carburetors, #2 and #3, and everything's been copacetic.


The Clutch:

I have, uh, not been kind to the clutch and it's started to slip again.

The new clutch I put in Columbo looks almost exactly like the old clutch in the pictures, right down to the funny-looking wear marks on Pressure Plate 2!

The clutch outer hub is fine; pristine; picture perfect; almost no marks on it.

The steels still look like new with no burning or varnish.

The frictions are a few fine frog hairs under 2.88 mm but the new clutch springs are sacked; under length this time.

The notches in the splines on the Clutch Boss Assembly and the wear marks from the clutch springs hitting the spring posts on Pressure Plate 2 are to deep to keep, they're toast.

I'm replacing the frictions and the Clutch Boss Assembly with spares from my (former) XJ11 but this time around I'm buying some Barnett springs from
Phat Performance Parts
Barnett Spring Kit 501-58-06045
Old Part# MT-45-6

Thanks for the ink and the link in another post by BA80!


FOR THE OIL WORSHIPERS:

I've used conventional oil, faux-synthetic, genuine 'spendy-synthetic (Redline), synthetic blends and they all work equally well.

The engine does not leak oil, it has never leaked oil and the only reason the clutch has started slipping is because I wore it out.

The type of engine oil used has never caused the clutch to utter so much as a single micro-supplication: it worked quietly, it worked hard and it worked well until I finally managed to wear it out.

I have used whatever oil was on sale locally and whatever I could find when I was out on the road -- never Passenger Car Motor Oil (PCMO), I was always able to find motorcycle oil or a Diesel Heavy Duty Motor Oil (HDMO).

PCMO, even in the bottles not marked "Energy Conserving" may contain some molybdenum but no 40 or 50 weight oil is ever going to get an Energy Conserving sticker so buyer beware!

Diesel spec. HDMO does not (yet!) contain molybdenum (MoS2 has sulfur and they're trying to get rid of sulfur in diesels) to mess up a wet clutch but keep your eyes on your fries, Jack!

.

[Orange4]

Way back to the carb diaphragm spring issue, I stretched mine about 7mm from how I found them (close to the spec listed in the post) so they were all equal and my XS now has super quick throttle response. Zero bog. So stretching them was not detrimental at least.

[BA80]

You can more than likely be just fine putting the Barnett springs in and not resisting the recommendation on oil.

Just give it a try, all it costs is $20 worth of springs and an oil and filter change.

Yes, AND filter.

[3Phase]

Orange,

I didn't stretch the springs except a slight tweak to make the short springs the same short length and the long springs the same long length, then I put 'em in the carbs and stopped messing with the springs.


BA,

The clutch parts are bad, not going to play with 'em so I'm getting new springs while I have this part of the enegine opened up.

After the trip back East and the filter almost-SNAFU I've pretty much decided to change the filter at every oil change whether the Fine Manual says it's time to drop in a new one or not.

I still have gallons of synth-blend, then I'll head to WallyWorld for some tube socks and beef jerky and whatever jugs-o'-oil are are on sale!



No Moly.
.

[BA80]

This is what I've been using for a while now.....

[3Phase]

The Supertech is what I had in the engine for (counts on fingers, removes shoes to count toes) carry the one ... ~3,500 miles until N'ahwlins.

I don't necessarily go by mileage, my finely-tuned foot telegraphs the correct oil change interval.

.