05 FJR 1300 Headshake

[DIY]

Here are the culprits I would check in no particular order, steering head bearings, bad tire, tire pressures, tires that provoke that steering behavior, suspension set up, worn out suspension, tweaked front end that binds up, loose steering stem nu, bent rim, and a bent frame. If it were me I would try to straighten the front end (loosen all the bolt except the top fork bolts and push the forks through their stroke then torque everything down again) and then see what happens. Honda ST 1100s use to do this as a result of their steering geometry when you took your hands off of the handlebars but I don't know about FJRs though. Also, Lou suggested a steering damper. I think that may be a mistake. A steering damper should be added to a properly functioning/steering motorcycle. It shouldn't be used as a band-aid for a system on the bike that doesn't function correctly. That can quickly descend into "hillbilly/ghetto" engineering.

 

[louemc]

Here are the culprits I would check in no particular order, steering head bearings, bad tire, tire pressures, tires that provoke that steering behavior, suspension set up, worn out suspension, tweaked front end that binds up, loose steering stem nu, bent rim, and a bent frame. If it were me I would try to straighten the front end (loosen all the bolt except the top fork bolts and push the forks through their stroke then torque everything down again) and then see what happens. Honda ST 1100s use to do this as a result of their steering geometry when you took your hands off of the handlebars but I don't know about FJRs though. Also, Lou suggested a steering damper. I think that may be a mistake. A steering damper should be added to a properly functioning/steering motorcycle. It shouldn't be used as a band-aid for a system on the bike that doesn't function correctly. That can quickly descend into "hillbilly/ghetto" engineering.

Lou suggested a Scotts Damper AFTER checking/removing ALL
Dumb-ass mechanical flaws that a dumb-ass has allowed to be on their bike.

 

[DIY]

Lou suggested a Scotts Damper AFTER checking/removing ALL
Dumb-ass mechanical flaws that a dumb-ass has allowed to be on their bike.

Ah! Sorry, reading comprehension is worse than usual this morning.

 

[Busy Little Shop]

Hiya Alan and Beth...
You have experienced a deceleration shimmy and it's normal...
some bikes may shimmy decelerating through the 45 mph range... keeping
your hands on the bars should arrest most of the front end shimmy...
some bikes shimmy more than others and it's no big deal with your
hands on the bars in the critical speed range... your bike should be
immune at speeds above 45 mph...

Deceleration shimmy is chiefly the product of non OEM or a worn
tires... it ain't the product of tire cupping... but low pressure defeat the tire's
corrective efforts... because every bike has this instability... it is held in check
by damping forces created mainly by the tire's self-correcting tendencies...

In short...

Deceleration Shimmy = front tire problems... (annoying)...

Wobble = front end problems... (could grow into the dreaded tank slapper)

Weave = rear end problems... (annoying)...

STEERING HEAD BEARINGS
If your steering head bearings are loose you'll notice a pronounce
clunk during braking...

If your steering head bearings are too tight the bike will weave and
not seek it own center...

I don't use torque wrench method to archive perfect torque rather I
raise the front wheel off the ground and tighten the steering head
bearings until the bars lock then I back off the nut until the bars
free wheel with a slight drag... with this method you find that sweat
spot and avoid over tightening and under tightening even if you
upgrade to taper roller bearings...

 

[Frisco]

My '13 does this and Ive researched the problem quite a bit. Bottom line, it just happens on many FJRs. It's less apparent with new tires, higher front PSI - I run 40, suspension upgrades, and load. Still does it on decel at 35-40 mph though. Just keep your hands on the bars and ride!

CJ

 

[Mr. BR]

next week while I'm off from work I plan on changing my Steering head bearings and the fork oil on my 60K '05 FJR.
Regards,
Mr. BR

To the OP, I started early on my bearing swap.... here's two FYI pictures of what's involved. Pretty easy so far. Hardest part was just getting the bottom bearing race off the stem. Anyway, I'm doing this while I've got the forks off for an oil change so the tapered steering bearings are just an upgrade of sorts.
Regards,
Mr. BR

 

[ST Guy]

Reading on the fjr forum those were the recommended pressures

FYI, check to see what Yamaha recommends. In almost all cases of people recommending high front tire pressures, it's due to anecdotal experience where people have raise their front tire pressure and reduced the hands off the bars wobble to some degree. Yes, it sometimes helps but is NOT what should be done. I've fought against this bullshit for years. What one is doing when the pressure is raised is narrowing the width of the contact patch which will help with the wobble some. However, doing this is at the expense of proper tire compliance and ultimately you've just reduced your contact patch surface area for such important things as cornering and braking.

Check to see what Yamaha recommends and stick with that. If the wobble is a problem check to make sure everything on the bike is up to snuff and if it's still there, go to tapered roller bearings in the steering stem. A good idea anyway.

 

[louemc]

FYI, check to see what Yamaha recommends. In almost all cases of people recommending high front tire pressures, it's due to anecdotal experience where people have raise their front tire pressure and reduced the hands off the bars wobble to some degree. Yes, it sometimes helps but is NOT what should be done. I've fought against this bullshit for years. What one is doing when the pressure is raised is narrowing the width of the contact patch which will help with the wobble some. However, doing this is at the expense of proper tire compliance and ultimately you've just reduced your contact patch surface area for such important things as cornering and braking.

Check to see what Yamaha recommends and stick with that. If the wobble is a problem check to make sure everything on the bike is up to snuff and if it's still there, go to tapered roller bearings in the steering stem. A good idea anyway.

So many Yes's

 

[scotinexcile]

FYI, check to see what Yamaha recommends. In almost all cases of people recommending high front tire pressures, it's due to anecdotal experience where people have raise their front tire pressure and reduced the hands off the bars wobble to some degree. Yes, it sometimes helps but is NOT what should be done. I've fought against this bullshit for years. What one is doing when the pressure is raised is narrowing the width of the contact patch which will help with the wobble some. However, doing this is at the expense of proper tire compliance and ultimately you've just reduced your contact patch surface area for such important things as cornering and braking.

Check to see what Yamaha recommends and stick with that. If the wobble is a problem check to make sure everything on the bike is up to snuff and if it's still there, go to tapered roller bearings in the steering stem. A good idea anyway.

Drpped the pressures to 36/36 as per the swingarm. Cut the headshake a bit, so will be looking at doing the stearing head bearings when I can get a hold of a big enough socket for the stearing head nut

 

[Mr. BR]

36mm socket needed.... I got one at the local Kragen/O-Reilly's. My bike is back together but I haven't taken a test ride yet. For 60K miles, my OEM bearings were still in good shape with no noticeable notchiness or detent felt when moving the bars back and forth. The tapered bearings are down right beefy compared to the OEM balls... so it's a good upgrade regardless and you'll likely never have to mess with them again.
Regards,
Mr. BR

 

[EastBayDave]

^ all good stuff above; listen to these guys. The ONE thing I didn't see mentioned is:

If your bike is "high mileage," & you've done all the fixes above including head bearings, the last thing is get the front end rebuilt by a quality suspension shop. OR check f/this specific symptom. Why you ask?

I've owned lots of wobblers, & discovered after doing all the above I still had "play" in the forks that's typically loose/worn bearings. If feels identical to head bearings but it's not. If you have that symptom, put the bike on a frame type (Pit Bull) stand, & get front end off the ground. (would be there if your changing bearings anyway.)

Get in front of bike, grab the -bottom= of BOTH sliders at the same time, & push/pull back & forth =front to back of bike. If you feel any play, or it clicks front to back, the fork bushings are worn out. This can induce wobbles as well...it's the same symptom as head bearings, but it might be both. Same feel to the bearings symptom. Why I typically do both bearings & bushings/fluid at the same time...

Hope this helps...

EBD