Great Technical Response

[AKRefugee]

My good friend, Cowboy, has a 2001 Yamaha 1600. He is starting to have some slippage in the clutch. I went on a search on the internet and found the Service Manual for his bike as well as a great write up on changing out the clutch springs, clutch disk and oil pump gear. (On some of the older 1600’s there was a weakness in the oil pump gear and many folks swapped them out when they did the clutch springs.) My friend looked at everything I sent him, including a website to get the parts he would need. He traded emails with the parts manufacturer with some technical questions he had and the direction it took cracked me up so much I just had to share it with you.

 

I have edited out non- pertinent stuff to shorten it and redacted company names to protect the guilty. Here is the email thread. Enjoy:

 

The Cast:

 

Cowboy – My friend

Max - President/Product Design

AKRefugee - Me

 

COWBOY: Hi Max, I sent a email yesterday about replacing the oil pump gear at the same time. Did you ask your fiend what he recommends? Hollerback Yah'll, Cowboy

 

 

MAX: This is all I could get: “Some earlier years had a weak oil pump shaft that could be upgraded.”

 

COWBOY: Max, Thank you very much for your quick response I'm going to do more research about that pump shaft. I've got the feeling that I'm going to replace that while I'm in there to do it right. Meanwhile if someone tells you of a recommended replacement pump shaft, manufacturer and part number, kindly pass it along to me. That would be much appreciated. Meanwhile I will be calling to do business with you within the next 3 weeks. You will be hearing from me. I'm impressed with your timeliness. Till then, Happy Trails, Cowboy

 

MAX: My brother is being a little thick headed…He does that

If I get more I will forward it along. Meanwhile YES replace it.

 

 

COWBOY: FYI, The engine oil pump drive shaft was not part of the transmission recall for 2001 Roadstars. There is superseded part # on this component meaning that Yamaha engineers did improvements to this part. I got this Information from a very reputable service shop manager and parts manager (redacted), (Service is Joe, and Parts is Steve). This is a bonafide Yamaha Retailer. So if anybody calls about all Roadstars up to 2001 (V1600's) and asks about this oil pump shaft it is recommended by many of the Yamaha Roadstar forums. The part costs $68.97

 

COWBOY: Max, Can you look into this because I need an answer from you or your engineers on this subject that has just come to my attention. Steve at (redacted) said something about clutch "cork" degradation as the clutches wear vs. Kevlar degradation. He said the stock clutches as they wear the cork sludge doesn't hurt the tranny but that the Kevlar degradation or sludge does. What's the skinny on this? Please reply.

 

THIS IS WHERE THE FUN BEGINS

 

MAX: My answer is simple- Stop listening to those nitwits

 

COWBOY: I hear you but I would like a technical answer to this. I know that they're trying to steer me away from your product. I am convinced that yours is a far superior product as far as performance is concerned but the affect on the wearability on the tranny in the long run is a concern to me as a consumer as well. I was a Senior Product Designer for 14 years in the defense industry so I do have a technical background. Please look into this for me. A plausible explanation of why this is not true is all I ask for. Thanks Cowboy

 

MAX: It’s a false negative. It is simply NOT true!

 

o The moon is made of cheese.

 

o “Not its not!” (max)

 

o How do you know you have never been there….!

 

COWBOY: Max, Please respond technically. I respect you, please respect my request.

 

At this point my friend sent it to me saying you won’t believe this you have to read this.

COWBOY: AKRefugee. I'm sending you this discourse that I had with the president of (redacted). Can you believe his responses ! Read Below. Unbelievable !!!!!

AKRefugee:

 

Wow, that was an "interesting" response.

One of those "trust me I stayed at a Holiday Inn Express" moments.

 

I will check my sources and see what they have to say. My gut feeling thought is that the Yammi guy really doesn't know s**t from shinola on the subject so he pulled something out of his a** that he heard someone else say one time. Remember this is the same shop that sent me out the door with rear brake pads that were so worn that they could have flipped in the caliper and killed me so I am a bit leery of their shops folks anyway. As far as I know, oil degradation is what causes sludge and that has nothing to do with the material being lubricated, only the operating temps and outside contaminants, but remember I did not stay at a Holiday Inn Express last night so I might be pulling something out of my butt as well ;-).

 

I have asked my friend to keep me updated on any additional responses and will post them here if he sends me anymore of this conversation. I just hope that the future responses as as funny as these last ones,

[bongobobny]

Very amusing!!

 

OK on the subject of Kevlar vs cork, kevlar is a lot stronger than cork and if there is any degredation of material, the kevlar partacles, in theory, will be a lot more abrasive than cork causing more parts wear potential as the same oil that goes thru the clutch also goes thru the entire engine. In reality the actual degredation of the kevlar is minute and the larger particles will be trapped in the oil filter, or should be. This brings up an entirely new topic of which oil filters are better but I'm not going into that here.

 

So, bottom line. Everything is about decisions. In this case do you want performance or longevity? If you want a more positive clutch then by all means go to the kevlar. If you are planning on driving the bike until the frame rusts out then stay away from the kevlar...

[Yammer Dan]

SHEEESH...I'm gonna go out to the garage and pound on my fingers!!!:bang head:

[bongobobny]

OK now to add fuel to the fire. Kevlar, being stronger, won't erode as much as cork...

[USCG-RET]

1600 Yammi. . .Road Star? if so. . have him sign into WWW.Roadstarclinic.com Awesome site with awsome peoples. . . .Post his question there. . .AFTER an intro or with it. He will get a response as to what to do. I will tell you that most will have that done with the Tranny recall. . .extra for the parts but labor is free. I had an '01 Star. . .traded it for my '06 TD! Money well spent. . .I loved that bike but I can't stay off my TD!

 

Just saying. . .

 

Tim

[AKRefugee]

Ok, got more info on this whole think. Max is not the actual manufacturer, he is a vendor that sells the kits. My friend actually got two emails. The first one from Max saying we are not xxx company quit bugging me with your questions, which my friend has done (along with taking his business else were. The second was from the actual manufacturer (Barrett) and was quite informative. I am including it here. My friend will be ordering directly from Barrett.

 

EMAIL: I'll try to give you a little background on the materials we've used in our 64+ years of making motorcycle clutch plates.

"Back in the day', as they say, and I'm talking British, European, early American bikes, cork

was the material of choice. The trouble with pure cork material was that as soon as it got oil on

it, it started to slip. Even if a clutch was designed to run dry, a seal would fail and oil would get

on the plates...slip city. In the fifties, Charlie Barnett came up with a material that he named -

Corperene. It was a mixture of cork, neoprene, resins, and other additives that not only was more

durable than pure cork but was also oil tolerant. He first made replacement inserts and later

started making finished plates by bonding this Corprene to metal cores. Leaky seals and gaskets

were a problem no more.

Corprene was the industry standard for years, but as good as it was, it wasn't perfect. What is?

As motorcycles design and technology improved, clutch design and materials evolved and improved,

also. Early bikes had 3,4,5,6 friction plates. While cork and Corprene had a high coefficient of friction,

both were fairly unstable when they got hot. They would expand, swell up and then contract when they cooled down. Could cause clutch drag, rough shifting, hard neutral. Tolerable in the older bikes with

few friction plates, but modern clutches now use as many as 12 friction plates and we had to develop

materials that are much more stable in hot and cold environments.Kevlar,carbon, ceramic, graphitics,

metallics are now used and are much more efficient and stable and durable than the old cork based

materials. All friction materials are made with a combination of resins and polymers and other base

components that formulate to create frictional qualities. Even cork-based materials, too.

Sludge was more common in the 'old' days when motor oils were formulated differently than today.

Modern oils, synthetics, blended and petroleum based, are much higher quality and less likely to

break down than the oils of yesteryear. Of course, if you burn up an clutch, any material and oil

combination is going to be messy.

We have never found that any non-metallic friction material to be more abrasive than any other. Clutch

plates used in automobile automatic transmissions are made of a type of non-cork friction material. The design and technology involved in the manufacture of these plates, closely parallel that

of motorcycles plates.

Our clutch plate design and technology has and will continue to evolve as it has for the last six decades. When the next great,new friction material comes along, we'll be the first to give it a try,

and get to the market.

Hope that helps you and I didn't ramble on too much....

Best regards,

Mike Taylor

Barnett Tool & Eng

PS....we still make plates for old BSA's, Royal Enfields, Nortns, Triumphs,etc, with Corprene...it

just works the best in those old bikes!