Possible explanation/fix for the some of YZ426 clutch problems.

[Skidplate44]

I work with a guy who bought a YZ426 3 weeks ago. While doing an uphill double, the motor abruptly stopped. The kick starter wouldn't move, and he felt it may have siezed. He took it back to the dealer and the dealer found that the clutch basket had let go, and a piece of it had wedged into the primary gear. The bike has been in the shop since Tuesday. The dealer is telling him that Yamaha made 2 batches of clutch baskets, and his had the "older" one in it, and they are putting the "newer" one in his bike. They are going thru the whole motor too. I will ask him to post an update Monday.

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Work a little, play a little, get lucky.

 

[RichardM]

Read below<p align=right>05-16-2000 :Edited

 

[RichardM]

What I think happens is the soak the plates in oil and causes the symptom to go away for a while an then it comes back. The bike shop that was grinding on my push rod was told to do this (soak plates) and it seemed at first the problem went away but returned the next day. I will also say this. I respect Rich's and others opinion that Mobile 1 15-50 works as well as Yamalube R and it seems to be the case in many bikes. After I replaced my clutch with a Hynson my problem went away. Because of the recommendation of people on this site, I bought Mobile 1 15-50. After I changed oil I noticed that the problem returned! Yes on my Hynson. Only for the first couple minutes after starting and riding, then it would go away. I changed back to Yamalube R and found that it never shows the problem. Now that is my experience and my opinion. There may be other factors that I am not aware of that caused this and the oils may be equal in quality and usability.

This is the only thing I do resent. Some people on DRN say that people who buy Yamalube R are stupid/foolish and are throwing away money by not using mobile one and that they are falling for a trap set by the motorcycle industry to gouge consumers. I am not one of those people, the manufacturer recommends this oil and claims it is manufactured for my bike. My experience has forced me to buy Yamalube R. I would like to buy cheaper mobile one but it causes a problem with my clutch. Now some might argue and try to convince others mobile one is the best and it may be but it did not work in my case and will state to anyone that they should use the oil the manufacture suggests for their bike. If they want to use a less expensive alternative and it works for them, great, but do not imply that people who put the manufacture correct oil in their bikes are idiots for doing so.

"Mobil 1 15W50 will work exceptionally well in a YZ400, or an XR650"
I do not agree with the statement above. It may work exceptionally well in other motorcycles but not mine (426) with a hynson clutch basket.&nbsp;&nbsp;There is a difference and in my experience the Yamalube works better and eliminates the problem and I will tell people of my experience. Take it or leave it. The manufacture says that Yamalube has a different makeup from automotive oils and it seems to work better in my bike. Are people who use Mobile one stupid for doing so? No, if I could I would use it as well and save money. I would say that anyone that says that mobile one is superior to motorcycle designated oils is making a statement not based in fact and neither lines up with my experience.

 

[Scott Senatore]

Has anyone had any good or bad experience running Golden sprectro 4 synthetic blend?&nbsp;&nbsp;I have about 20 hrs on my 426 and have not experienced ( and hope not to ) any clutch problems.

 

[mrg426]

I bought my 426 about 5 weeks ago and it has been in the shop for 2 of the 5 weeks. It seems the oil sump bolt came out and went to war with the clutch basket. Needless to say the motor is being rebuilt. thanks yamaha<p align=right>05-16-2000 :Edited

 

[Rich Rohrich]

Richard - I would never recommend that someone who has more than a few easy hours on a clutch switch to Mobil 1, or ANY oil with significantly different properties than the oil used for the majority of hours. Wet clutches can be fickle, and making a sudden change on a multi-hour race bike clutch is asking for trouble. The examples I routinely site are based on simple low stress breakin on standard mineral oils, followed by a change to Mobil 1. I've never attempted to change to Mobil 1 mid stream on a used clutch, and I doubt if I ever will, my guess is it wouldn't be a particularly good idea.  I don't think anyone ever said Yamalube 4R wasn't a good oil, just that it was significantly overpriced compared to comparable products. It would be idiotic to call someone an idiot for using any high grade motorcycle oil from a major manufacturer, but IMHO it is idiotic for people to believe that ANY oil has magical properties.  Some oils will have the ability to mask gearbox problems, the huge number of people who have found relief from poor shifting two-strokes by running ATF is a testament to that, and in your case at least it appears that Yamalube 4R has had a similar effect. I'm happy that Yamalube 4R helped alleviate your problems, but assuming Mobil 1 is some sort of generic prescription for trouble in these engines seems pretty short sighted to me.
I don't think Mobil 1 is some panacea by any means, but the ability to change the oil at least twice as often for the same dollar value provides a useful incentive for most riders. Old depleted Mobil 1 ISN'T better than fresh .99 cents a quart Kendall GT in these engines, and seeing lab reports on HIGH dollar oils after 100 racing miles has comvinced me that changing oil is FAR more important that picking a MAGIC brand.

I guess we'll just have to agree to disagree about the relative value of products

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Rich Rohrich

"The only time I become discouraged is when I think of all the things I like to do and the little time I have in which to do them."

              - Thomas Edison<p align=right> 05-16-2000 :Edited
[ By Moderator ]

 

[CHIP]

I am not quite sure if I understood correctly Richard. Did you also change the clutch plates. It seems to be that because of the problem with the basket that the plates wear unevenly. It may be that any oil used would still give you the same old results with already worn plates. The Yamalube could be masking that. Again, this is just a guess. I had to contact my dealer today to let them know that my bike is again doing the same thing even after their"so-called" fix. I had to demand that they call Yamaha and they agreed. I feel that the basket is the root of my problem and that the plates have suffered un-mercifully because of it.

In short...I love the bike...The clutch stinks...Yamaha corp. has been cooperative....the suspension rocks...the engine pulls like a tractor on pure alcohol...and except for the clutch I still love the YZ426

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Chip
__________________________________________________                                              
If It's Too Loud, You're Too Old!!!
__________________________________________________
00 YZ426F (mine, all mine!!)
00 XR70R (my son's)

 

[RichardM]

Rich,

I never said you said idiot, it was someone else. We do disagree on oil properties though. My bike had the problem from the very beginning. I took it back to the dealer right away. The mechanic said there was no damage to the plates. After the Hinson basket was put in, I rode my bike on tues, wed, thurs, sat and sunday for a couple weeks because I had been without my bike and needed a big 4stroke fix. I would seriously doubt if those clutch plates were not broken in. I did not abuse the clutch but do give it a work out. I never believed that Mobile one was a generic prescription but after the bike was broken in I though my clutch problems were over and could enjoy the savings many others get by using it. My experience leads me to believe that motorcycle oil that uses a different stock and formula works better for me and seems to better lube the clutch plates but it may be an incorrect conclusion.
I do agree that changing oil often it the best insurance. I was not trying to single you out as one who proclaims mobile one is the best but there were others. From what I have read your posts have been well thought out, and as accurate as they can be for the information you have.

Chip, perhaps your clutch plate were toast buy mine was not at the time of the Hinson clutch replacement. In fact I have a KX500 that I rode while my 426 was having problems. Like yourself I like my 426 but because of all the problems I have had with it (not just the clutch) it really puts a damper on things and makes me think the 426 is not as bullet proof as everyone has stated. Not to brag but I have a 98 500, sold my 99 YZ400 for a 00 426 and will probably get another bike next year. Point is I am not like many people who rave about a bike that has a bunch of problems because can't afford to get another bike for a few years. Many people don't like to admit they made a bad purchase. I believe I made a mistake getting this bike and am waiting with baited breath for Honda to produce a competing 4 stroke they are known for quality, IMHO Yamaha does not. Regardless, as long as Jeremy is winning and the mags hide the clutch, transmission, carburetion problems Yamaha will lead in sales. I will seriously consider not buying a Yamaha after this travesty regardless of how good the mags say they are.

 

[CHIP]

I understand how you feel RichardM and I meant no disrespect about the plates. I got a call from the dealership today and was told that they had been on the phone with Yamaha(Andrew, the customer rep) and was given the go ahead on a taking out the clutch assembly and that they would be replacing the plates and basket. The kicker was...and I quote..."Since the bike is already out of warranty and is strictly a competition bike, this is pretty much a GOODWILL JESTURE and that it is an ISOLATED INCIDENT"..My comment was...Yeah Right!! First of all, RichardM you and I both know it is not an ISOLATED INCIDENT and second of all, they would not do this if it were.

I guess I should not say anything negative since they are repairing the situation, for now, I would still buy another one although they could cause me to go the other way, I actually have not been a Yam fan since my first ride(77GT80)

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Chip
__________________________________________________                                              
If It's Too Loud, You're Too Old!!!
__________________________________________________
00 YZ426F (mine, all mine!!)
00 XR70R (my son's)

<p align=right>05-18-2000 :Edited

 

[RichardM]

I am happy for you Chip, you saved a few hundred dollars. The reply from customer service just makes me think Yamaha lies and does not take responsibility for there bikes under warranty. They did in your case but not mine or many others. I would be a fool to buy another one, just a side note. On my 99 400, the sprocket came loose and threw the chain through the case. I thought it was a lack of maintenance on my part. I had it welded up and stronger higher tensile strength sprocket bolts put in. I never had another problem. Since I was aware of this problem I would check the sprocket bolts on the 426. Guess what, in a matter of 30 minutes on the track last weekend the bolts came loose and shattered my rear hub. I guess that is insult to injury for me. My bike out of warr and anyone not knowing me would say it was probably lack of maintenance. My KX500 has been bullet proof for almost 2 and a half years. The rubber pipe hangers for the pipe break sometimes but the parts are cheap. I may have a 2001 Kx500 next year. I want to sell the 426 but I have a desert tank, skid plate, and spark arrestor for it and I am sure I will take a money hit on it. Oh well.

My advice, change out your sprocket bolts to higher tensile strength ones with red locktite. No one else may have had this problem. I do not personally know of any. I have went over several times in my own mind what could have happened. The first time it happened on the 400 I was using wd40 on the chain because I was out of lube. The 426 I had just changed to MFR lube. Maybe they both are penetrating and overspray got into the threads. Maybe I over tightened a bolt (doubtful used torque wrench). Maybe I am hard on the bike or it can't handle fat dudes. Maybe the bike assemblers had hangovers from the night before. Maybe God is telling me not to buy Yamaha. (Laying blame must also allow for personal responsibility) Or I could just be a terrible mechanic. Who knows.

By the way, one of the local guys here was having problems with the carb, it kept fouling plugs. After changing everything out Yamaha gave him a new carb. I think his was out of warr as well. I am not conviced this years YZF is anything close to the other models. Everything that has been changed, clutch, carb, etc I have heard of people having problems with.

My dealership has been great though. They have given me parts at cost and have put me first on the service list. I may not buy a Yamaha but I will buy another bike from them. With all the new street bikes coming out, I may want to get something faster. My Vmax does not give me the adrenalin rush like it used to. Maybe I will have better luck in that arena and stick to something I know works (KX500)&lt;p align=right&gt;05-18-2000 :Edited<p align=right>05-18-2000 :Edited

 

[CHIP]

RichardM,
  I can appreciate totally your reasons for not being satisfied with Yamaha. It seems that the Lemon truck was at your dealership the day yours arrived. If I had the continuous problems that you have had, I too would not want to buy again.
  Question(s)....Where would I get the higher tensil strength bolts? What is the difference between blue locktite and red?

Also, not to take advantage of a bad situation but if you decide to sell and want to unload the add ons, I would be interested(ie: Big Tank, skid plate)

Note: Laying blame and taking partial blame. That is an extremely rare and admirable thing to do. My father taught me all my life that no body is responsible for ourselves more than ourselves. his saying: Blame, Shame and Justify! Once we begin to blame others it is to shame them to Justify or make excuses for ourselves. You also turn your complete power over to them to be able to correct the situation.     JUST A PERSONAL NOTE AND SOMETHING CLOSE TO ME THAT I BELIEVE IN--  I will get off the soapbox now  --

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Chip
__________________________________________________                                              
If It's Too Loud, You're Too Old!!!
__________________________________________________
00 YZ426F (mine, all mine!!)
00 XR70R (my son's)

<p align=right>05-19-2000 :Edited

 

[RichardM]

Hi Chip,

Recommend is a strong word and&nbsp;&nbsp;I take it back. I do not recommend anything outside what the manufacture says and though it may be obvious people reading anything on the internet check with a qualified mechanic or someone who knows what they are doing unless they are willing to experiment at their own risk. This is my experience and was done buy a qualified mechanic to my YZ400. You can order the higher tensile strength sprocket bolts from Moose racing supply. Most dealers have a catalog. Stock is about has a rating of about 8.5 and the ones from Moose are about 16. The idea behind doing this is it allows you to tighten the bolts down tighter. On Page 5-2 of the manual it states 30 ft-lbs for torque. With these bolts you can use 35 ft-lbs or a little more(Funny how Yamaha recommends locktite for the front brake disk but not for the sprocket. I know the stock bolts are the self locking type but in my opinion they do not work. Red locktite has a stronger hold. When you are at you local auto parts store, read the packages, it explains it better than I could. The possible downside to doing this: Over tightening the bold could break or weaken the hub (not very likely but possible, more likely you will sheer the bolt off) Using red locktite could make it difficult to remove the bolt and you may have to drill it out (also not likely, but in the automotive work it has been though to seize some bolts but that is debatable as well)

Personal responsibility. In trying to figure out what happened to my hub I have to include the possibility that I was at fault. It would be foolish not too. The 426 transmission pin, clutch basket, and carb problems (bog) are Yamahas responsibility under warranty and it seems they only take care of customers in or out of warranty in "isolated incidences" to quote the rep. (They did not want to get me a new basket, they wanted to keep grinding on my push rod)
<p align=right>05-20-2000 :Edited

 

[threestrokerKDX]

I know im a little late on this but i just got a 2000 426 and im having the same problem. What exactly was the best fix. Call my dealer, drill or grind something, or get a new basket?
Nic

 

[DesertDog]

Went to the spring service school last month, and we talked about the grabby clutch problem, and how it doesnt show its face on 2001 model 426's, The fix is to run the frictions and steels from the 2001 426, they said it would fix the problem.

 

[J.B.426]

This is the solution from Tim Ferry's factory mechanic. Hope he doesn't mind me reprinting it.
Post to all with clutch problems:
Go to your Yamaha dealer and get the anti-judder spring, plate, and friction plate that is std in the 01 426.
The problem is that the innermost plate sticks to the clutch hub. The spring kicks it away from the hub. The spring is a flat surface spring the same dia. as the clutch plates. it must rest against a hardened washer. Also the first steel plate is also hardened. Finally there is a special friction plate that is thinner to allow clearance for the spring washer.
I hope that wasn't to confusing. Kinda hard to describe in words. I hope this info helps.
BK
Yamaha Factory Race Team

 

[Ando]

Had the same problem with a customer's '00 YZ426F. Extremely grabby clutch that hooked up hard with no slip. Compounding this problem was the fact that this customer had dual-sported the bike, so riding the bike in traffic was interesting to say the least. When pulling away from a stop the bike would either stall or wheelie.

Talking with Yamaha technical support they recommended replacing the parts with the updated units including springs and clutch basket, and if the problem persists, clearance the clutch pushrod end by a small amount ~ 0.005-0.010 in to provide for better more even oil flow to the clutch discs.

This cured our customer’s problem completely. Any decent dealer should help you with this by talking to Yamaha technical support.


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Ando
Just another day in Paradise
Two Wheels, Kauai