Fried clutch plates.. what do you think caused it?

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dman

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I have been having a hard to shift in neutral when hot problem. So I was going to do the "easy fix". I pulled the clutch plates to find that the back plates were smoked and had a little wire trapped on them. Any ideas what caused this?
 

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Personally I junk the wire, half disc, and two dampening washers. In this case it looks like they did all but getting rid of the wire may have caused issues with the clutch since it didn't stay in place.
 
It looks like 1 friction disc and 1 steel disc are bad.
 
Personally I junk the wire, half disc, and two dampening washers. In this case it looks like they did all but getting rid of the wire may have caused issues with the clutch since it didn't stay in place.

Now that you mention it Sean, I did exactly that on the last clutch I did (plus the heavy duty spring)…using bits I acquired from your organization as I recall!
 
Ya there was the two springs and the half friction disc (sorry I didn't post a picture of them) I'm definitely doing the double d mod and getting rid of the wire, half disc and washer. Half that spring is somewhere in my engine pan now..
 
If your sump, oil drain plug isn't magnetised, make it magnetic. But a magnet in your oil filter if you like too. Don't use friction modified oils. With double up diaphragm spring you will notice the clutch lever is heavier but it won't slip. You'll feel the difference when you accelerate in 3rd, 4th and fifth. When the red oil light comes on you know you are doing it right.(Red oil light senses oil level in the front of the sump but the oil pick up is in the rear.)
Stay upright
 
With double up diaphragm spring you will notice the clutch lever is heavier but it won't slip.

...additionally removng the half plate and washer you wll notice the gear change will be more clunky and may hear some additional noises from the clutch at idle.
 
If your sump, oil drain plug isn't magnetised, make it magnetic. But a magnet in your oil filter if you like too. Don't use friction modified oils. With double up diaphragm spring you will notice the clutch lever is heavier but it won't slip. You'll feel the difference when you accelerate in 3rd, 4th and fifth. When the red oil light comes on you know you are doing it right.(Red oil light senses oil level in the front of the sump but the oil pick up is in the rear.)
Stay upright
You'll feel the difference when you accelerate in 3rd, 4th and fifth.
If your clutch in OEM-spec is healthy, I doubt you'll have any difference in acceleration from using a double diaphragm spring in your clutch. I'd be interested to hear Sean provide feedback.

I never had a OEM clutch diaphragm spring 'go-bad.' I've replaced friction discs when the clutch started slipping, along with scuffing the 'steelies,' checking for overheating/bluing, warpage, thickness, and clutch basket slot wear. I'm not a drag racer, so I don't make a habit of revving the engine and dumping the clutch from a stationary start. I do enthusiastically run the engine into the upper third of the rev-band in a roll-on, but I don't speed-shift, where I leave the throttle wide-open, and hit the clutch lever while toeing the footshift. The PCW replacement heavy-duty diaphragm spring is what I use, and it's easier on your hand, by a far-margin, compared to doubling the OEM diaphragm spring.

If you are drag-racing a bike with a power-adder, or you have a hairy-build 1500cc engine, then maybe the double diaphragm spring is a good choice. Where I live, a stop & go idling-along traffic jam in traffic is commonplace, and the exertion of operating a double-diaphragm spring drivetrain isn't anything I would want.
 
The Double D mod or using something like the stronger pcw clutch spring eliminates any stock slipping. Yamaha intentionally made the clutch the weaker or breaking point. Strenghening that area moves the weaker point to the driveshaft or final drive IMO.

Mark
 
The Double D mod or using something like the stronger pcw clutch spring eliminates any stock slipping. Yamaha intentionally made the clutch the weaker or breaking point. Strenghening that area moves the weaker point to the driveshaft or final drive IMO.

Mark
My friend's shop when he built a 1500cc power-adder, fully-ported w/bigger valves, and converted to Suzuki shim-under-bucket valvetrain for a customer, snapped two driveshafts before getting a tool-steel Exactrep part. As Sean has mentioned, better to lose a driveshaft than break an expensive modified engine case.

VMax 1508 cc cams-Suzuki followers.jpgVMax 1508 cc big valves.jpgVMax 1508 cc pistons.2.jpg
 
You all have valid points.. I ride the bike hard but I don't smoke the tires. I just bought a set of oem steels and oem friction 8 and 7.. so mu plan is to get ride of the wire, half disc and two washer.. the question is if I only put one oem spring in, will that cause the clutch to slip?
 
No, my opinion, is, from your self-report of riding habits, it shouldn't slip, assuming no problems with the OEM spring. The PCW spring replacement is a good upgrade.

Call them if you want info on the heavy-duty diaphragm spring. Less lever-pull than the double-disc, and it helps clamping pressure.
(518) 859-6669

173 East Main Street
Amsterdam NY 12010

Lvlhead's Vmax - Into The Clutch

The Barnett pressure plate alone probably costs more-than replacing your OEM friction discs and getting the PCW heavy-duty diaphragm spring.
Yamaha VMX12 V-Max (1985-2007) - Barnett Tool & Engineering (barnettclutches.com)

VMax Barnett  pressure plate.png
 
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Pistons have space for valves. are they OEM? Does it mean, it is not interference engine?
To me, a 'non-interference engine' means that in the event of a broken cam chain or cam-drive belt, the valves will not contact the pistons. Don't expect this on a VMax.

The left is OEM, right is not.
 
Wow, piston on the right looks over 10% bigger at least.
 
Does pcw go under another name? I tried looking it up and I couldn't find any site that sells that stuff..
 

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