News:

This forum is run by RPM and donations from members.

It is the donations of the members that help offset the operating cost of the forum. The secondary benefit of being a contributing member is the ability to save big during RPM Holiday sales. For more information please check out this link: Membership has its privileges 

Thank you for your support of the all mighty FJ.

Main Menu

steer wobbles

Started by las1200, January 14, 2011, 07:39:45 PM

Previous topic - Next topic

las1200

Hi FJ's

Please advice.
Today noticed my FJ steer wobbles alot in road irregularities if i i'm not gripping steering. It happens at different speeds.
Never noticed this before.
Tire pressure? It looks ok.
Front suspension problem?

thanks

racerman_27410

time to adjust the steering head bearings

front wheel off the ground

with handlebars centered give a little push sideways

handlebars should fall to the stop but not bounce back off the stop

if it bounces tighten them up

dont tighten them too much or you can open a whole nuther can of handling worms.

good time to check and make sure there is no notchiness in the movement of the bars.

KOokaloo!



andyb

Also happens with worn front tires.  Also can happen with new tires if they're an aggressive profile.


SlowOldGuy

Be sure and check everything Frank mentioned.

But, every time I had/have this problem, it's 100% a worn or badly cupped front tire.  It's most noticeable during decelleration from about 50 MPH with my hands off the bars.

Some tires can even cause this when new.  My best example is the now discontinued Metzeler MEZ2.  It had a somewhat zig-zag center tread that cause a pronounced wobble from the day it was installed.

DavidR.

Travis398

+1 on the front tire. my bike did that for a little while but went away after a couple hundred miles.


When all you have is a hammer, everything looks like a nail.

weymouth399

Wasn't that a high speed wobble you had Travis :dash1: during the NEFJR.
It couldn't have been a result of Nobby or Eric MAKING you go that fast :rofl:
Then when you slowed down it doesn't do it anymore, huh magine that.
Bob W

If your tire is slightly cupping, you can take a belt sander to it carefully to round off the square parts.
80 grit or less, it will surprise you how well it works.
I have done it to get a little more out of a tire, can we say (cheap basterd)

Bob W
84 FJ 1100
86 FJ1200
89 FJ1200
5  FJ POWERED race cars
76 LB80 Chappy
93 KX500 ice for sale
00 KX500 ice/dirt
04 KDX220 dirt for sale
04 KX500 ice
08 KLX450 ice/road
72 CT90x2 for sale

carsick

Bob, I can understand DOING these type of things, but admitting and recommending them? You've been watching Red Green again.

weymouth399

No just tried to get a 1000 more miles out of my stock tires.
It was more of a test, we profile our racecar tires ice tires that way and I wanted to see if it would work. (like a champ)
Bob W
84 FJ 1100
86 FJ1200
89 FJ1200
5  FJ POWERED race cars
76 LB80 Chappy
93 KX500 ice for sale
00 KX500 ice/dirt
04 KDX220 dirt for sale
04 KX500 ice
08 KLX450 ice/road
72 CT90x2 for sale

las1200

ok, doing bearings test and see what happens.
tire looks ok, pressure ok (35psi-2.5bar) and no obvious degradation.
it's a dunlop sportmax, any comments on these tires?

do I need special tool to loosen and tight stem nuts?
by the way, how do you usually maintain front whell up for maintenance (long periods)?

thank all the for help! :good2:

RichBaker

Tire pressure is LOW.... should be 38f 42r, unless you're a skinny little guy.
Rich Baker - NRA Life, AZCDL, Trail Riders of S. AZ. , AMA Life, BRC, HEAT Dirt Riders, SAMA....
Tennessee Squire
90 FJ1200, 03 WR450F ;8^P

Harvy

Quote from: RichBaker on January 17, 2011, 05:32:00 PM
Tire pressure is LOW.... should be 38f 42r, unless you're a skinny little guy.


Rich....I could take offence at that.......hahahha.

Us skinny little guys like 36F/42R.


Harvy
FJZ1 1200 - It'll do me just fine.
Timing has much to do with the success of a rain dance.

Harvy

Quote from: las1200 on January 17, 2011, 04:57:28 PM

do I need special tool to loosen and tight stem nuts?
by the way, how do you usually maintain front whell up for maintenance (long periods)?

thank all the for help! :good2:

Stem bearing nut..... a big spanner is all you need..... The manual has torque numbers, but I have always pulled it down as tight as I can (so the bearings are seated, and then loosen it so that I have full movement l-r with no bounce back......works ok for me.
Remove the handlebars, remove the acorn stem nut on the top of the top triple, remove the top triple, remove the top bearing nut/washer. Adjust the bottom nut as above. Re-assemble it all.

Front wheel........ remove the chin fairing, place a block of wood across the header pipes forward of the centre of balance and jack it up so that the front wheel is just off the ground, but not high enough that you are either grounding the rear wheel, or trying to lift the whole bike off the centre stand.

HTH
Harvy
FJZ1 1200 - It'll do me just fine.
Timing has much to do with the success of a rain dance.

markmartin

Quote from: Harvy on January 17, 2011, 06:23:11 PM
Quote from: las1200 on January 17, 2011, 04:57:28 PM

by the way, how do you usually maintain front whell up for maintenance (long periods)?


Front wheel........ remove the chin fairing, place a block of wood across the header pipes forward of the centre of balance and jack it up so that the front wheel is just off the ground, but not high enough that you are either grounding the rear wheel, or trying to lift the whole bike off the centre stand.

HTH
Harvy



Would this work?  I had to put a scrap piece of wood (2"x8")  under the center stand so I could 'teeter- totter' the back end down while an assistant shoved the stand under the frame. This should hold the front end up. (ignore the scrap wood under the rear tire--I was working on my shock in that pic, so holding the rear wheel up in the process)





Harvy

Don't see why not Mark..... I recon you could support a battle ship with that.  :i_am_so_happy:

Harvy
FJZ1 1200 - It'll do me just fine.
Timing has much to do with the success of a rain dance.

weymouth399

Mark great carpentry skills, who knew :biggrin: just some scraps lying around, humble too :sarcastic:
Bob
84 FJ 1100
86 FJ1200
89 FJ1200
5  FJ POWERED race cars
76 LB80 Chappy
93 KX500 ice for sale
00 KX500 ice/dirt
04 KDX220 dirt for sale
04 KX500 ice
08 KLX450 ice/road
72 CT90x2 for sale