darkside wobble

[big al]

Just went to a ct put about 150 miles on the the bike today the only problem was when i passed a car and went back over into my lane at about 80 mph the bike started to wobble. i read a few post about the head bearings and shock bushings both are good went through the bike over the winter so my question is i have a falken 512 speed rated h i think it is a pressure issue i have 40 psi in it now should i go up or down

[Warlock]

Just went to a ct put about 150 miles on the the bike today the only problem was when i passed a car and went back over into my lane at about 80 mph the bike started to wobble. i read a few post about the head bearings and shock bushings both are good went through the bike over the winter so my question is i have a falken 512 speed rated h i think it is a pressure issue i have 40 psi in it now should i go up or down

There are several things that can cause it. Head bearings, rear shock bushings bad. Weak shocks. Also different roads, front tire could be worn some. I have had a wobble even with a M/C tire on back. I use to run a 412 and a good tire. I found the side walls a little too soft for my liking. I tend to run a C/T with a stiff side wall. I've had a worn front tire to cause a wobble. You might want to try different pressure settings. Some times that plays into the wobble. How many miles on the bike? A good way to check the head bearings for index and jack up and turn it real slow from side to side. Sometimes you can feel it. If still unsure remove the front tire and turn it again. If it is index you will know with the tire removed.
David

[Mr. Nuts]

My Falken wobbled too but didn't start until 90-100. Rode it for about 15,000 and it never changed. Went back to a bike tire and no more wobble. I loved the car tire but will try a different brand next time. Maybe due to the directional nature of the Falken or just a mismatch between front and rear.

[big al]

the bike has 95000 miles over 20000 of them are mine replace head bearings and all wheel bearings over the winter swing arm bearings felt good. I have been riding for over 30 yrs everything from dirt bikes to crotch rockets dual sports now onto crusiers for the last 4 years, it felt like the side wall of the tire was flexing

[old2soon]

Try upping the P S I into the 44  46 range. What does the side wall of the tire indicate as max pressure?? I have a General ultimax h p in back. Started out about 44 45 psi and am now at 36 psi. Have a metz 880 up front i keep at 42 psi. The tires were mounted new together. I have over 7000 miles on this setup and have ZERO issues with it. Hope you discover what the problem is-are -was. RIDE SAFE.

[Warlock]

the bike has 95000 miles over 20000 of them are mine replace head bearings and all wheel bearings over the winter swing arm bearings felt good. I have been riding for over 30 yrs everything from dirt bikes to crotch rockets dual sports now onto crusiers for the last 4 years, it felt like the side wall of the tire was flexing

I run a Bridgestone G019 car tire. I have run several rear car tires and so far I like this one the best. It has a good stiff side wall. I would wear that tire out and try a different tire next time. I see you did some maintenance. How did the top shock bushing look? They are the ones that usually wear out. It will make the bike handle that way also. I've had mine in the triple digits with the Bridgestone and no wobble issue. I know the wobble is not a fun thing to experience.
David

[big al]

i just replaced the top shock bushings again when i put the c/t on it seems like they only last about 8,000 to 10,000 miles but then again i mostly ride 2 up and pull a trailer a couple times a year

[Warlock]

i just replaced the top shock bushings again when i put the c/t on it seems like they only last about 8,000 to 10,000 miles but then again i mostly ride 2 up and pull a trailer a couple times a year

I'll try and find the P/N of a nylon bushing I use from McMaster Carr. They hold up real well and cost is less than a $1.00 a piece.
David

[sugerbear]

ran a falken 512 on my 2k I/S 40-42 psi. no wobble to top end.

[R J]

Running a Good Year TT, w/36#.

Pump the front tire into the hi 40's.

Then pump the CT up, ride it, NO wobble, lower the pressure 2 to 3 # and ride it again.  Still no wobble, lower it 2 to 3 # again.

Repeat the above till the wobble comes back.   Then up the pressure 2# and that should put you in the ballpark.

[PhredValk]

I have over 7,000 miles on my Falken Ziex ZE-512 205/65R-16, H rated tire. Been over 100MPH on several occasions, up to 120 just cause today out in the country. Never a wiggle. Had 37PSI in it from the installer and I've never had reason to change it. Dyna beads and chrome 90º stems.
Check your tire ballance.
Fred.

[Ricky-D]

Trying to turn a car tire into a motorcycle tire by pumping the pressure up isn't necessarily the best solution.

There are many factor that can cause a wobble, maybe it's the front tire!

The first checks should be to look at all the mechanical reasons that can cause a wobble.

Looseness in any suspension parts can cause wobble.

A death grip on the handlebars can cause a wobble. Have you considered that?

Do the simple and easy things first to try finding the problem.

Have you experimented on different driving surfaces?

You don't indicate with what bike you are experiencing the wobble.  Some have had wobble originating from the attitude of the windshield. A loose fairing on an Interstate can cause a wobble.

To simply lay the reason for the wobble on the car tire is non-productive and may obscure the real reason for the wobble.

***

[FryeVRCCDS0067]

I had the same problem with both my GY TT's but it didn't surface till speed was over 90-95. Tried new stem bearings, new rear shocks (440's), progressive springs, new front tire, new wheel bearings, was still there when riding solo but not when riding two up for some reason.

It seemed to be sometimes triggered at lower speed by passing vehicles and crossing the indented lanes which the weight of vehicles puts into some of our paved roads. You can't even see these sunken areas much of the time unless you are stopped or there is rain collecting in them. How bad they are and how much they may effect you seems to depend on countless variables, probably including your windshield size and shape.

It hasn't happened to me since I started running the General tire but I don't think I've been over 100 with it yet.

[Michvalk]

Mine did that until I got the CT broke in. Up the pressure until you get a few hundred miles and then lower until you get a decent ride. I started at 44 lb and have settled at 38 lb. Smooth as glass!

[Jabba]

Al went darkside?  HOLY COW!!

When do you head to the Mosque?

I run 32 PSI on my std with a Falken.  I run 41 on the IS with a Altimax.

Jabba

[HayHauler]

Al went darkside?  HOLY COW!!

When do you head to the Mosque?

I run 32 PSI on my std with a Falken.  I run 41 on the IS with a Altimax.

Jabba

Different big al.  Look at the post count...

Hay 
Jimmyt

[NITRO]

I've had no problems in 12,000 miles with my GYTT wobbling. I keep it around 33-34 psi and it feels great. I did notice that at 35 psi the cycle was less stable in corners and needed a lot of correction. Try playing with pressure and see what feels best for you.

[wdvalk]

I have the same thing happening with my falken,mine starts in at about 80mph,new metzler front,new front wheel berrings,new shock bushings,its almost like a side to side sway,I am running it at 40psi,would really like to find the solution,really dont want to go back to $300.00 dollar tire changes every 7000 miles

[Warlock]

i just replaced the top shock bushings again when i put the c/t on it seems like they only last about 8,000 to 10,000 miles but then again i mostly ride 2 up and pull a trailer a couple times a year

Found the bushing. Use this p/n    6389K344
http://www.mcmaster.com
David

[FryeVRCCDS0067]

Al went darkside?  HOLY COW!!

When do you head to the Mosque?

I run 32 PSI on my std with a Falken.  I run 41 on the IS with a Altimax.

Jabba

Different big al.  Look at the post count...

Hay  

Jimmyt

Ahhh! I was puzzled too.

[big al]

update  went up in psi to 50 rode up to 105 mph no wobble started to drop pressure 2 lbs got down to 44 before it started to wobble again so as of right now i will run it a 46psi for about the next 5 to 6 hundred miles and then try to drop the pressure again. thanks for your input and the shock bushing #

[mikeb]

Mine did that until I got the CT broke in. Up the pressure until you get a few hundred miles and then lower until you get a decent ride. I started at 44 lb and have settled at 38 lb. Smooth as glass!

i found the same thing true it takes 1000 miles to train the car tire .. so dont give up on it

[2qmedic]

Interesting, it took me about 1200 miles for all to get setteled in.

The wobble:
replaced shock bushings - helped
increased rear tire psi - helped
progressive shocks - wobble dissapeared

Cheers

[Rio Wil]

Several of the 2 lane roads where I live in the Sacramento River Delta levee have the right edge of the lane marked off with either white or yellow paint. Just outside that paint is about a foot wide strip of rumbles cut into the asphalt to wake you up in case of  whatever.  A similar row of rumble strips are cut into the center marking lines.  If I pass a car and pull back into my lane in front of the passed car with the bike at a lean, as soon as the front wheel hits these rumbles, it sets up a wobble.  Straighten up the bike and the wobble subsides. If I stand the bike up straight before hitting the rumbles, it is solid as a rock.  It appears that with the bike leaned over a bit, the reduced traction of the front tire crossing over the rumbles  is enough to induce wobble.  Other wise the bike is stable well over 100 mph, rear tire is a Pirelli P4/42 psi with 35k miles and the front is a lightly used Dunlop (i think)/42 psi.  The bike has 145 k miles and original head bearings, swing arm not been touched and shock bushings are a bit loose.  My primary intent is not to solicit any fix it suggestions, but to point out the relationship of the front tire loosing about 50% of its traction passing over the rumbles and causing a wobble.  There are several big sweeper curves in the area that can be cruised at 80+ and they are not without bumps.  But it appears a single or maybe two closed spaced bumps are  not enough to upset the stability but  several small ones such as the rumbles are......just saying..

[Tropic traveler]

Had a 205/65/16 Michelin HydroEdge, wobbled at 95+. This was on the '99 Valk. Never took it above 105, too chicken. None of the Avons I had/have on the other Valks shook or wobbled at any speed. Recently replaced CT with Dynabead balanced Avon. Silky smooth at any speed, no wobble or shake. To be fair I suspect the balance job on the Michelin was not the best.
JUST MY OPINION.... CT's are harder to balance when squeezed on a skinny Valkyrie rim.

[Jabba]

Al went darkside?  HOLY COW!!

When do you head to the Mosque?

I run 32 PSI on my std with a Falken.  I run 41 on the IS with a Altimax.

Jabba

Different big al.  Look at the post count...

Hay 
Jimmyt

Oh... I was afraid I was going to see apes running things when I woke up.

 

Jabba

[HayHauler]

Good one Mr. Jabba.. 

Hay 
Jimmyt

[Paxton]

I run the least expensive C/T on the market; NEXEN 5000 205/65/16. - $89 bucks.
Have never experienced problems at any speed. 

Originally had the pressure @40 PSI. It was good. Then, I read posts discussing different tire pressures and such...
So, I went up to 44 PSI ... no problems. However, the increased feel of road imperfections was too harsh for my taste.

So, I pulled over to the side of the road and let air out the old fashion way... just counting seconds and using a tooth pick...
I was pleasantly surprised  how plush and smooth the ride became...

Got home and let the bike rest and cool off overnight. Checked the pressure in the morning and it was down to 28 P.S.I.   
Took it for a ride under various road conditions riding it hard, zigzaggin... then up to 110 MPH. Not a single problem.
Smooth as a loaded Hearse! 

So, 28 PSI is my preferred  c/t tire pressure... I love the silky ride.

NOTE: I run 11.5" inch progressives and I ride solo.

Here are some pics...
https://picasaweb.google.com/103917731019176896112/SHEDRAGONFLY?authkey=Gv1sRgCODNo622qI7UHQ