death wobble at 115+mph

[nightfox85]

hello again all
i noticed that after about 115mph i get alot of front end wobble and i just wanted to confirm my suspition that its only the wheel bearing and not the head stearing bearing. there is no clicking turing the bars, no over or under steare, and no bumps or shakes at any other speeds, just wanted to double check with everyone before i ruled out the head bearing. also could this just be a tire pressure problem??? let me hear from some of the seasoned V-vets

 

[naughtyG]

99.9% chance it IS your steering head bearings. It happens when they're loose, as well as when they're worn.

On a 1985 bike (what mileage?), I would bet just about anything that they're in need of renewal.

On my '86, they felt fine until I removed the wheel, bars, forks etc, then had a feel again. Without load I could feel the roughness, and when I took them out I realized just how bad they were.

Don't kill yourself - replace them now.

 

[nightfox85]

really, i mean im not pushing back or anything but i have no symptoms other than the wobble past 115 and i really dont want to mess with the trip tree unless i have to. thank you though.

 

[maleko89]

Steering bearings are worn or loose.

 

[nightfox85]

bleh, is it a very involving process to change them

 

[naughtyG]

it really isn't that hard, it's just the bottom race that's a bitch to get out. The top one just pops off when hit from underneath.
The easiest way to get the bottom out is a bead of weld - it contracts and drops out when cooling. The long and hard way is to do a couple of cuts very carefully with a Dremel wheel, then break it in half and get it out.
Well worth it if you wanna get rid of that wobble, other keep well under 120mph - I've been there more than once and thought I was gonna die - seriously!

 

[nightfox85]

thanks guys.:worthy:

 

[Heretic]

A bad or worn front tire would do it as well, but as others have stated it IS probably your steering head bearings given the age of your ride.

 

[vmax626]

bleh, is it a very involving process to change them

So is embalming a dead body.
think about it.
<<Dave>>unk:

 

[zippo6]

Well put Dave.....

 

[Buster Hymen]

bleh, is it a very involving process to change them

Post where you are in Texas. Maybe someone on the forum is close and can give you a hand.

 

[Shuriken]

I feel your pain. I'm wondering what to start on to eliminate the death wobble on my bike....

http://www.vmaxforum.net/showthread.php?t=9203
http://www.vmaxforum.net/showthread.php?t=4456

I will probably just go through everything: wheel bearings, steering head bearings, swingarm bearings, and address front forks. If that doesn't do it I'll change the front wheel.

 

[gamorg02]

wheel or tire? i'm happy with my new steering damper

 

[Shuriken]

wheel or tire? i'm happy with my new steering damper

Post details. Price? Brand? Where did you buy it? How has it helped specifically?

 

[gamorg02]

i was going to do a writeup on it shortly. the quick and dirty:

Brand: shindy
price: $200 ish
buy it: targa acc, but i had a retroactive price
here's targa's store:
http://cgi.ebay.com/ebaymotors/V-Ma...0791735QQptZMotorcyclesQ5fPartsQ5fAccessories

and one being offered @ $200:
http://cgi.ebay.com/ebaymotors/SHIN...temZ330330352080QQptZLHQ5fDefaultDomainQ5f100

i broke the frame bracket and they immediately sent me a replacement, so i'd pay the little extra even now to go with targa. i've also attached instruction sheets

helped:
i only had 1 wobble, decel wobble when i hit uneven pavement. it has gotten rid of that on the highest dampening setting, bu tmakes the bike unsteerable at slow speeds. so on long highway runs i put it at the highest dampening.

on the higher settings (there are 7) it has also gotten ride of i'd say 90% of those uneasy feelings when hitting bumps and not straight up and down at high speeds.

 

[Shuriken]

Thanks. Did you post pics of it installed and I just didn't see them?

 

[gamorg02]

http://www.vmaxforum.net/showthread.php?p=103415#post103415

 

[naughtyG]

None for 85-92?

 

[gamorg02]

i just noticed i guess not. doing some quick math, that would equate to what a roughly 10mm (to be on the safe side) smaller circumference, right? there def isn't 10mm of room left where the bracket meets.

you could probably call targa acc (the store i bought it from) and ask them. I worked with a guy named "robert"

but a quick online search turned up this:

http://www.hyperformanceparts.com/c...-Damper-Stabilizer-1985-1992-Yamaha-VMAX.html

i'd probably check before ordering, make sure its a different fork bracket.

also if u look at the directions i posted, there is two different models:

17-406 for the earlier years. i'd try targa acc as they have a 30 day money back guarantee as well

 

[naughtyG]

i just noticed i guess not. doing some quick math, that would equate to what a roughly 10mm (to be on the safe side) smaller circumference, right? there def isn't 10mm of room left where the bracket meets.
/QUOTE]

How do you mean 10mm? Old forks were 41mm, new ones are 43mm, that should mean a difference of 2mm, right? Are you talking about the forks bracket?

The other link you found seems to be for the right model, and about $200 too, so that's pretty good. Worth a shot for sure..