Death Wobble at 110 with car tire?!?!? Yoko Envigor

[BradValk48237]

All,

 I was on a trip this weekend... Great weather in Michigan, except some rain as we were going thru the "Tunnel of the Trees" into Mackinac.. nice ride for 700 miles except......

On the way home, was heading south on US75 to the Detroit area and bored, so I opened her up- just to clean out the carbs-

So I ran her up to 115 on the speedo, have done this many times before, and let her stretch her legs for a few miles... this was on a stretch of road I had done it before on. 3 lanes with little traffic, I was on th outer lane....

All was fine until I took a right hander, highway curve, nothing to sharp, jus usual sweeping turn

About the middle of it she started to wobble... ass end I think, but in that situation it's hard to tell....

So I let off the throttle... probably a bit too much as it got worse...Like scary worse!

Put some throttle back on and brake, let off and eventually I steadied out of it and slowed down.... not a flat, and it stabled right back out.... ran 80+ MPH the rest of the way home with no more issues that I could tell, but the road was mostly straight and did not want to try that again until I got home and looked things over.

First thought was low tire, but still had 37-38 lbs in it.... This is in a Yokohama Avid Envigor tire... I had a Falken Ziex on it last time and never had this issue....

The shock bushings were replaced 30k ago with VTX ones and looked and felt OK when I mounted this tire early this summer.... front tire is older, but still not close to the wear bars...

I don't remember hitting any bumps in the road, but it was grooved pavement....And I did not make any hard corrections in the turn.. nice and smooth til' she threatened the tank slapper....

SOOOO... has anyone else had any issues with the Envigor at higher speeds??!??!?

It is possible that the bushings are getting worn, but like I said they looked good.

Thoughts? Was this just a one time thing? Air pressure to low? (I filled it to 40 now- but not going to test it yet)

Any help appreciated.

B

[WintrSol]

What is/was the pressure in the front tire?

[BradValk48237]

38

[old2soon]

38

           I M H O-bit low. Try 43-45 P S I. RIDE SAFE.

[Firefighter]

I have the same tire with 40 psi front and rear, and mine has the death wobble at about 85mph gps depending on the wind. The wind and road conditions seem to get the wobble started. I have replaced every bearing on the bike except for engine bearings. New rear shocks, rebuilt front shocks, everything I can think of and I still can have this wobble. Had my fairing off once and did not wobble but not sure how fast I was going. Have had the rear saddle bags off with the wobble still there. Once when the wobble started I speeded up to see what would happen and it turned into a tank slapper and I feel lucky to be alive, could not even keep my feet on the pegs. I try not to test it like that anymore. Be Carefull!

[csj]

I'm about to put my third car tire on. Looking forward to trying the high speed again,
to see if the usual wobble is there.

In my case it's always the shock bushings that are 'mushed'.
When I replace the bushings the wobble is gone for about 5K,
then it returns, and it's always the bushing.

The kind of tire and the air pressure seem to have little bearing.

[The emperor has no clothes]

I had that happen with the Avid Envigor once. I think my speed was closer to 95-100. It was in long sweeping turns. I bumped the pressure up about 4psi and had no more issues. There was also a cross wind that probably contributed to it also. I'm running an Avid Ascend now. Haven't had any issues with it. But I rarely get past 100 any more. So to make a long story short, yes I do think it's air pressure.

[Harryc]

Aren't there polyurethane bushings for a Valk that would not wear so fast?

[The emperor has no clothes]

Aren't there neoprene bushings for a Valk that would not wear so fast?

Yes. The VTX or F6 ones are poly. Hold up much longer than the stock ones.

[Skinhead]

I'd run at least 40 psi front and back, especially if you plan to run 100+.

[Chrisj CMA]

Wow, is it that common to get death wobbles on car tires?

[Skinhead]

Wow, is it that common to get death wobbles on car tires?

No, it's not.

[The emperor has no clothes]

Wow, is it that common to get death wobbles on car tires?

No, it's not.

+1  I've got about 75k on car tires. Only one incident, and I wouldn't call it a death wobble. More like an unsettling vagueness in the rear in hard sweepers. I think you might get the same with an under inflated bike tire at speed also. I did have a death wobble on a Yamaha RD350 once at 100mph. The front end got so light at that speed it went into a head shake. That was pretty scary, but I was 17 and was invincible . 

[Willow]

I run a Falken.  It would wobble a bit in a slight lean at speed until I got the pressure up to 40 pounds.  I run 42 on the front.

If I were running thirty-eight in front or rear I would consider it a good soft ride but wouldn't think about maneuvering at 100 mph.  YMMV

[Steel cowboy]

Have you checked your steering bearing for proper torque.

[BradValk48237]

Thanks All....

I Have put the rear up to 40-41 and the front to 40..... That should help

I dont do it all the time, but 100+ happens...LOL

I went over the bike again, pulled one of the shocks and the bushing still feel good.. not washed out, but gonna order some anyway....

I think its a combo of the tire and the situation...... New tire to me, lower air pressure (I used to run 36-38 in the Falken with no trouble), the grooved pavement, possibly wind.....etc....

Now I need to look into the best way to control it IF it does happen again.....

B

[Blackduck]

How many miles on the shocks?
Have experienced that wobble with a car tyre a few years ago.
Bike always felt a little loose on corners and on a fast weekday run in the country the rider behind said the back of the dike was moving in corners.
Replaced the shocks and it is a completely different bike.
The problem is as the shocks loose efficiency over time you do not realise it is happening.
The higher the pressure in the tyres the harder the shocks have to work due to less side wall flex, could also be part of the reason for shock rubber failure.
If you like to push it at times I would seriously look at new shocks
Cheers Steve

[Ricky-D]

Could be a "death grip" inducing that "death wobble". Jus sayin, wouldn't be the first time.

***

[Jess from VA]

Any death wobble discussion should distinguish Interstates from Others (although the OE shields are pretty big).  (and it looks like early posters all have interstates)

I run ISs with CTs at 40 PSI constant.  I've 440s with solid bushings and good head bearings.  I've had some high speed wobble from time to time, and I think it's a combination of high speed and the aerodynamics of the big fairing and shield and pods and trunk and winds and curves and dips/bumps in the road which starts the wiggles (which once started, then get progressively worse).  I don't think it's the car tires at all. (assuming you have good rubber and PSI on both ends)

[dago mooserider]

I had the exact experience as the O.P. a while back. I have a standard that was always rock solid at speeds over 130 mph. I added chrome wheels, new front tire and honda hard bags from a tourer model and that's when the I started getting the wobble. Started around 110 and got worse and worse as I kept going. Somewhere around 130 mph, I actually remember apologizing to my mother as I prepared to die. I think I did have the "death grip" Which worsened the situation. I don't run a windshield and already have to hold on tight at those speeds. I assumed tires, wheels out of balance so pulled them and had them re-balanced-didn't help at all. I pulled the hard bags off and it was gone-not even a hint of wobble. So, I'm convinced it is some kind of aerodynamic thing. I'm shocked this hasn't come up more. Maybe I have another issue and the bags exacerbate it? Anyway, try removing your bags and see what happens. btw I'm on m/c tires

[Firefighter]

Death Grip has nothing to do with it in my case, the wobble starts easy then accelerates in a hurry.

Dago,  as I said above, I removed the bags and the wobble was still there. My IS wont go 130mph unless I was down hill, then maybe. Windscreen makes alot of drag. Speedometers very fast also.

[Alberta Patriot]

Wow, is it that common to get death wobbles on car tires?

I installed a C/T on my Yamaha Stratoliner that had 4000 miles on it.
At anything above 80mph I could get that death wobble with very little warning...scary as hell actually.
Went back to a M/T and never had the wobble again...right up to 130mph...no problem.
Not saying it is common but for me it was just too risky.
BTW that tire was installed by a shop that uses a digital dynamic balancer.
They sponsor some sport bike club racing so they need to balance tires that will be running at speeds up to 180mph.

[SPOFF]

The snide reply would be to "not run car tires." But I've been riding Valkyries since 1997 and remember the violent death wobbles from the first gen Avon motorcycle tires. So it's not a car tire thing.
I run a cheap General Tire station wagon tire at low pressure because I want a lot of sidewall flex. This seems to handle best  for me.  Due to failing eyesight I rarely exceed 50 mph, so I can't shed any light on high speed wobbles. Although occasionally the rear tire will track cracks in the road so vigorously that I pull over expecting a flat  to discover it's just the lousy roads.

[Firefighter]

SPOFF if I snided, didn't mean to. I still ride CT, never said that is the cause of any wobble. I think it is wind, road and aerodynamics, could be something else.  I don't know.

[jmann]

I'm on my 3rd yoko envigor and while I have only run to 115 once or twice I have never experienced the wobble at any speed and I run the slab at 80-90 frequently. I use ride on as a balancer. I get 20-25k out of the yoko and it handles as close to a m/c tire as anything.

[Tfrank59]

SPOFF if I snided, didn't mean to. I still ride CT, never said that is the cause of any wobble. I think it is wind, road and aerodynamics, could be something else.  I don't know.

I have to jump in here, though I'll probably get hammered for it...this is a touring machine we're riding, not a race bike.  I think anybody who runs 100+ on public highway on a Valkyrie, especially an old 1500, is asking for death (regardless of which tires you run).  If you want to ride at those speeds, get a racing motorcycle and go to a track, wearing all appropriate racing apparel.  You may still end up a grease spot but at least you will have done it right, and you won't further poison cage drivers against us riders.  Just my 2 cents.

[Alberta Patriot]

SPOFF if I snided, didn't mean to. I still ride CT, never said that is the cause of any wobble. I think it is wind, road and aerodynamics, could be something else.  I don't know.

I have to jump in here, though I'll probably get hammered for it...this is a touring machine we're riding, not a race bike.  I think anybody who runs 100+ on public highway on a Valkyrie, especially an old 1500, is asking for death (regardless of which tires you run).  If you want to ride at those speeds, get a racing motorcycle and go to a track, wearing all appropriate racing apparel.  You may still end up a grease spot but at least you will have done it right, and you won't further poison cage drivers against us riders.  Just my 2 cents.

I have easily run up to 100mph while passing someone...well past where that wobble would scare the hell out of me(Eg...You know...that A-Hole who speeds up when you try and get by him)
I am NOT arguing one way or another...to run a C/T or not is your choice, but if you have a "Death Wobble" maybe take that tire back to have it re-balanced or replaced with another choice. The wider the tire the more important a "Dynamic" balance is. If you feel the tire is not the issue...make sure you find out WHAT IS...it is your butt on the line.
Re:  the comment that M/C tires can wobble too...my same comment still applies.

[Brian]

While I have never taken my 97 standard over 100 I have experienced this wobble on a highway doing over 80 on a long left turn bend in an interchange. I run the General Altimax HP. In my case it ended up being the cupped Dunlop front tire. No longer running Dunlop, switched to Avon. Have not experienced the wobble since. 40-41 psi in the front, 30-32 psi in the CT.

[Stitch_in_La]

Friend of mine picked up a wobble in his Yamahammer said he was checking out bearings shocks etc. told him check his front tire, he said tire looked fine plenty of tread, told him check again the side wear.  center tread looked great, left side was wore much more than the right, left hand turn picked up a wobble.  New tire later rides fine.

Stitch

[dago mooserider]

I have to jump in here, though I'll probably get hammered for it...this is a touring machine we're riding, not a race bike.  I think anybody who runs 100+ on public highway on a Valkyrie, especially an old 1500, is asking for death (regardless of which tires you run).  If you want to ride at those speeds, get a racing motorcycle and go to a track, wearing all appropriate racing apparel.  You may still end up a grease spot but at least you will have done it right, and you won't further poison cage drivers against us riders.  Just my 2 cents.

shenanigans!
https://youtu.be/hQibCYxUfC4