Death wobble

[Dave the Carpenter]

You do not have to touch the neck bearings when doing fork seals so chances are they never looked at them ! Yamaha did not put crap fir grease in the neck or swingarm bearings from the factory . I have seen wobbles from the rear and people thought it was from the front.

Thanks for the info Captain. I’ll have the bearings serviced and go from there. It bothers me that I’m relying on others to do some mechanical repairs. I’ve done my own vehicle repairs for 50 plus years and rarely needed to go to a shop. It’s different with the bike. YouTube sure is a great go-to but the lack of lift devices needed to do some services is a challenge. I suppose I can rig up some straps on my engine crane and give it a shot. I’m also coming up on the valve adjustment interval , read the procedure, learned that Toyota has the shims available at a lower price than Yamaha. I joined this forum in October, asked my first question a couple days ago and I’m impressed and grateful for the responses. Semper Fidelis Dave Heitman

 

[Parminio]

I would have thought Yamaha, and other motorcycle manufacturers would have very experienced riders, probably ex-factory racers, test their bikes who would push them further than most of us on here ever would or are capable of hence am a bit surprised they would release a bike with an inherent very dangerous problem.

Do you really think they had Lewis Hamilton test drive the Corvette?

Also, it's not a dangerous problem. The "factory" doesn't do final assembly of the bike, the dealer does. Any issues you have with a bike from the dealer are because they had some idiot putting the bikes together.

Brother Dave; I suggest you get the stabilizer.

Sorry I can't help ya with stabilizer experience, it's too late for two of my maxes.

The amount of really bad information in this thread is staggering.

 

[Dave the Carpenter]

As the Captains suggests ensuring the bearings are in good condition and set up correctly you don't need a damper.
Also check wheel bearings and run-out and that both fork tubes are parallel.

All that fitting one would do is try and mask the real problem.

Thanks Max

 

[dannymax]

A member of this forum bought a new '07 which had a wobble. Returned to the dealer several times and cause nor solution was ever found. He sold the bike with about 1K on the clock.
I'm sure some of you older gents remember this....?
Texas lad as I recall.

 

[Parminio]

That dealer probably had an idiot mechanic that had no clue what he was doing.

I couldn't find a picture of a Vmax but this is how a Yamaha, or any motorcycle for that matter, typically arrives at the dealership:



I was at the dealership when they uncrated my 2007 and it was very similar to this. The front tire, end exhaust, handlebars, controls and all were not on the bike.

They had to do all of that themselves, and if they didn't bother to do it properly you WILL have a wobble. That comes from not torqueing the steering head bearings properly on final assembly.

Edit to add:

 

[dannymax]

I could be talked into bringing that Commando home!

 

[sandy klock]

I would never suggest someone not put something on their bike that could potentially save their lives and save them great expense. Especially something as cheap as a stabilizer. I remember people lined up tire to tire at Thunder to have John do his Furbur Fix. Maybe you heard of him. What did it fix? Possibly a high speed wobble that vmaxes don't have. Virtually everyone there. That is still the way most vmax people set bearings. Yes sometimes a new tire will fix it. Replace it before it shows wear. How many vmaxes have worn rears? Factory test riders ride on smooth tracks and generally ride thru speeds that upset things. A speed you don't want to hit a bump at. The worst was honda v65s. You can usually accelerate and brake thru the speeds that cause problems with little more than a handle bar wiggle. I guess a bigger fork brace is a band aid to fix other problems by some people's thinking. Man have they sold a lot of them to vmaxers to fix a non existent problem.

 

[sandy klock]

I would never suggest someone not put something on their bike that could potentially save their lives and save them great expense. Especially something as cheap as a stabilizer. I remember people lined up tire to tire at Thunder to have John do his Furbur Fix. Maybe you heard of him. What did it fix? Possibly a high speed wobble that vmaxes don't have. Virtually everyone there. That is still the way most vmax people set bearings. Yes sometimes a new tire will fix it. Replace it before it shows wear. How many vmaxes have worn rears? Factory test riders ride on smooth tracks and generally ride thru speeds that upset things. A speed you don't want to hit a bump at. The worst was honda v65s. You can usually accelerate and brake thru the speeds that cause problems with little more than a handle bar wiggle. I guess a bigger fork brace is a band aid to fix other problems by some people's thinking. Man have they sold a lot of them to vmaxers to fix a non existent problem.

PS: I think Jonny Carson's son was killed by a V65 wobble but that was in 80,s and I don't remember a lot from that era.

 

[MaxMidnight]

That's an opinion, not a fact.

I've briefly trawled through t'internet and although I cannot find any articles about what testing the factory carried out, a number of magazines did reviews. MCN comment on the handling but none mention death wobble.

I'm happily to be corrected, but am I'm sticking to the opinion that the cause is due to an out of spec. (e.g. worn) component rather than inherent problem in the design.

Correct, that's what 'IMO' states. Much of what is written on forums are opinions; nothing wrong with that but (IMO) it should stated as so...which is what I did.
I'm agreeing that, as you say '...a bit surprised they would release a bike with an inherent very dangerous problem.'
I try to make it clear that when diagnosing an issue one should always try to work with facts and not opinions, gut feel and the like.
That is why in post #4 I suggested additional checks to which other contributors have added their suggestions.

From many of the road tests that I recall the handling was not considered one of the bikes best features but that wasn't an uncommon comment for many of the larger capacity bikes of that era. However, that related to going around corners and not strait line stability.
As far as I know the only one that had a strait line issue was the Suzuki TL1000R(?) with its rotary rear damper.

 

[02GF74]

Do you really think they had Lewis Hamilton test drive the Corvette?

Also, it's not a dangerous problem.

I don't know if Lewis Hamilton was one of the test drivers for the Corvette but as he had a contract with Mercedes to drive F1, I doubt he would moonlight doing test driving.

If we are talking death wobble = tank slapper, then from the videos I've seen, it is very dangerous as the bike is out of control (I've never experienced one).

Re testing. My comment are based on what I read in 2 books : The illustrated motorcycle legends Kawasaki and Classic motorcycles Kawasaki

Quote from the latter ; (re Z1)
A year later the first prototype was well advanced and in the spring of 1971 it ran at the Yatabe test track.

... With the USA being the major target, the next phase was a test programme in that country and early in 1872 two pre-production prototypes were extensively tested in the states.


The point as was trying to make is that I expect that Yamaha tested the Vmax so any death wobble would have been discovered and addressed rather than leave the testing to Joe Public.... but that is conjecture since I have no evidence for either.

... not to mention the litigation issues should the death wobble be inherent as part of the design snd it could be proven that Yamaha did not test the Vmax.

Anyways, have a happy Christmas and safe riding in 2022 and what remains of 2921.

 

[Fire-medic]

Sometimes I don't read before hitting 'enter either.

safe riding in 2022 and what remains of 2921.

early in 1872 two pre-production prototypes were extensively tested in the states.

I had a chance to buy a Commando, but I passed on it. I think the crated one pictured may be from the shop in the Detroit area (British Only, Garden City MI) which had one still in the crate, it was auctioned-off. I bought parts from them for a Triumph I had to sleeve and replace the piston.

I don't look at someone's request for info on a steering damper as anything different than someone else wanting to install a NOS system, a 4/1 exhaust, (no Cobra 4/4's please!) or anything else. It's their bike, they choose their mods. If it makes them 'whole,' have at-it. Sure it's helpful to offer suggestions on how to deal with something that's giving them problems. That's why I so-often include a link to the factory manual in my replies to service questions. "Follow the factory instructions," is usually the best way to proceed.

I also often suggest making use of the 'search' function, and the 'advanced search' is utilitarian in its function. I've made the comment, "whatever issue you're experiencing, someone on-here has already faced that and has posted about it, you just need to locate the thread(s) and see what transpired." Some people are computer neophytes, or they may-not have one, and they are working-off a smartphone. That's a harder row to hoe. I like to try to make things easier for myself, that's why I use the shop manual, and before proceeding upon something I may-not have done before, I will see what I can find online. You have to be able to separate the wheat from the chaff however. You can find misinformation on the internet (wikipedia) (TikTok) (youtube) and it's up to the reader to be able to perform that editorial function. On occasion I've mis-stated something, and someone catching that corrects the record, and I acknowledge my mistake. Some people may-not be able to tell what's good info from what's bad info, and that's where you have to rely upon the factory manual, and subject matter experts like Sean Morley, dannymax for carburetors, CaptainKyle, or other knowledgeable members.

Members come and go, but the base of knowledge on-tap is enough to fill your mug. You just have to know how to get that full draught, and then taste it. The flavor of success when dealing with a particularly-vexing issue is sweet indeed.

 

[Parminio]

If we are talking death wobble = tank slapper, then from the videos I've seen, it is very dangerous as the bike is out of control (I've never experienced one).

Of course it is. But you laid that at the feet of Yamaha. It is not Yamaha's issue. It's a poor mechanic's issue.

 

[sdt354]

Kyle mentioned the grease issue, and most bad bearing sets wear notches in the races on our forks anyway. Metal to metal in one spot of the race taking the hit after every bump. Lack of lube accelerating wear for sure. So if you don't take it apart for inspection and a grease packing, you can adjust bearings per the bounce test method and still be loose when the forks are centered. I like to seat the bearing, back it off then bring it down again a couple of times. And I'll run as tight as I can without a weave at lower speeds. There's a torque wrench method too. I know you old wrenchers got a feel for setting preload on a tapered bearing.

 

[02GF74]

Sometimes I don't read before hitting 'enter either.

I make mistakes but in this case I left those for comedy effect plus I knew all readers would be smart enough to figure it out.

 

[Fire-medic]

About the 'bike stilll in the crate,' years-ago, I dropped by the local Ducati & Bimota dealer, and an acquaintance of mine was there to collect his newest purchase. It was a Bimota Tesi, still in the crate. He brought a film camera (yes, awhile ago) to document the 'reveal,' as the Millennials call it these days. I stood-by & helped him as-needed. I was tempted to take the cardboard home, after-all it said, "Bimota" but I decided I had enough J/T/D around the house. It was an interesting day, to watch that alternative front-end come-out of the crate. He collects Italian bikes, and cars, and he ran his own garage as a 'sole-proprietor' servicing expensive European cars and Asian cars. He would frequently have millions of dollars' of cars there, being worked-upon.

One time I stopped by to see what was going-on, and he had an Aston-Martin Lagonda coupe, a Porsche turbo, a Bentley, and two Toyota 2000 GT's, those go for around seven figures these days. Another time he had a brand-new Countach with its engine on a cradle, next to the car, the owner had burned out the clutch in < 2000 miles, and the dealership farmed-out the job of replacing the clutch to him, as he was a certified Lamborghini mechanic. He started an AACA event in the spring in Ft. Lauderdale, he told me, "I just opened my Rolodex and started calling my customers, to bring their cars to the near-oceanfront park where the event was held." I have some great pics of the cars, all on film. It was that-long ago.

 

[TBrooks47]

Sandy, thanks for your input. I also read of the death wobble being present in new Max’s back in the day. My front tire is new and balanced by a local dealer. At the same time , the fork seals were changed so I assumed ( I know....I’m an ass...) the head bearings were adjusted at reassembly. Maybe the seals were replaced w/o the steering head having been removed. I’ll ask. The rear tire is somewhat worn. I’ll replace that and see if it helps. The wobble occurs at 115 and above. I’ve seen 130 sans wobble but that was a while back. Bike has 22k miles, is immaculate, but stuff wears out so........Finally, sometimes I wonder if it’s rider input. With the throttle cranked wide open, and me ducking the breeze, I wonder if I’m pushing the right side bar and causing the problem, I’ll keep chasing that dog till I figure it out cause I want to do the Texas Mile . And as an aside, I’ve seen claims of stock Max’s touching 150. “ I’ve had mine over 150 many times”.....******** claims like that....... The Texas Mile , to me, is the place to find out. I’m not one of these idiots who think the Interstate is the place . Plus, I’m 72, so if I’m gonna crash....the Mile is the place to do it. Medical people on site. Thanks again, Sandy. Merry Christmas/Kwanza/Hannukah/Festivus. Semper Fidelis Dave Heitman

In my experience with my 06 a new front tire with a worn rear tire is asking for trouble.
Even with everything in spec the more pointed peak of the new front with the rounded off peak on the worn rear will definitely cause issues at speed
I added progressive suspension front and rear. Added some frame and fork bracing from Sean Morley and with same mile tires my Max corners pretty good

 

[dannymax]

This is only my opinion but after spending a bunch of time researching data I came to believe there are almost as many reasons for a wobble as there are bikes with wobbles. Sometimes it's crappy assembly...but not always, sometimes it's a bad bearing (several possibilities here)...but not always, sometimes it's tire wear, excessive rotating mass...but not always. You see where I'm going...there is no 'one size fits all'!
And it's not a unique problem to the Yamaha Vmax...GP bikes wobble under certain conditions, Isle of Mann bikes too...it's not inherent to the Vmax, it's inherent to motorcycle design in general.

I cured a wobble by going to 17" wheels & Metz radials...other guys tried that with no change.

 

[Fire-medic]

Here's another vintage bike still in its crate. It's a 1973 CZ 400cc 'coffin tank' motocrosser. This is a bike before the advent of the long-travel suspensions. The CZ's were also very-successful in ISDT racing. I was racing my '72 Yamaha 360 dirtbike I bought new against CZ's, Rickman/Zundapps, Rickman/Montesas, Pentons, KTM's, Puchs, Bultacos, Montesas, OSSA's, and 'the usual (Japanese) suspects,' when this bike was put into its crate. I still have it.



Here's a similar CZ, a 250cc, also with the same style 'coffin tank.'

 

[Vinmax]

PS: I think Jonny Carson's son was killed by a V65 wobble but that was in 80,s and I don't remember a lot from that era.

Carson's son car accident in '91:
https://www.latimes.com/archives/la-xpm-1991-06-25-me-1322-story.htmlhttps://news.amomama.com/154952-heres-how-johnny-carson-lost-his-son-ric.html

 

[ATKPILOT]

I need steering head dampener suggestions. Thanks happy holidays Dave The Carpenter

Ohlins by far but check kneck bearings swingarm bearing etc it's usually that I used to teach several roadracing schools and slot of my students had that problem I told them your holding on to tight and it always fixed it