weird head shake

[Wishbone]

So with a 50-60lbs tool bag strapped to my tail I get some bad head shake at 38-45 mph. Like it almost gives me a tank slapper with my hands off the bars. With just me, or me with a passenger it's non existent. Bike is an 02 fz1 with race tech cartridges and what ever other gmd voodoo in the front and a penske out back, both sprung for 230# rider with gear. I'm a little over my ideal weight at 240 with no gear. The bike has been down twice. Once by the previous owner from a wheelie gone wrong. Once low sided by me at about 60 mph. The forks and triples have been straightened but never had the frame measured. I replaced the steering head bearings about 20k miles ago. The rims and tires are balanced with pirelli angels with about 3k miles on them and seem to be wearing evenly.

The only other time I experienced this with this bike is with an old crappy set of touring tires (dunlops I think) and I just wrote it off as old crappy tires, since it went away with new sneakers.

Anyone know what it could be? I was thinking Maybe the steering head bearings but that's just speculation.

[Chippertheripper]

make sure the pressures are correct too.

[TheIglu]

Check the bearings. My steering head bearings loosen up once in a while on the KLR and the ZRX. Snug them up, make sure they are where they need to be.

[BluGixxer]

My guess. I don't know what compound your tires are, but 3K on softer tires is a lot, I have never gotten more than 3K of usefullness rubber on tires. Even if I tried running the tires advertised recomended pressure. (36 psi ish) it seems you can't see anything wrong, but they just act different. Get some new tires.

[Uncle Snake]

New front tire cured that on my ZRX.

[beet]

Don't ride with a tool bag batabing.

[Tricky Mike]

fuckin' Beet rules.

[Stromper]

Head bearings are tricky but that is where I would start.

[ChicknStripEatr]

Bent rim? Happened to me. The bars would shake between 55-60mph. You could BARELY make out the imperfection with the naked eye. Only when the front end was off the ground and you spun the wheel by hand.

[CBR929RE]

My guess. I don't know what compound your tires are, but 3K on softer tires is a lot, I have never gotten more than 3K of usefullness rubber on tires. Even if I tried running the tires advertised recomended pressure. (36 psi ish) it seems you can't see anything wrong, but they just act different. Get some new tires.

Pirelli Angels are a Sport Touring tire that should last much longer than 3k miles.

[Wishbone]

make sure the pressures are correct too.

I was down 2 psi in both tires.

Check the bearings. My steering head bearings loosen up once in a while on the KLR and the ZRX. Snug them up, make sure they are where they need to be.

BINGO! Didn't realize they got loose. But it's a no brainer since they specs call for it to be tightened, loosened, then tightened to a lower ft/lb

My guess. I don't know what compound your tires are, but 3K on softer tires is a lot, I have never gotten more than 3K of usefullness rubber on tires. Even if I tried running the tires advertised recomended pressure. (36 psi ish) it seems you can't see anything wrong, but they just act different. Get some new tires.

New front tire cured that on my ZRX.

I usually burn out the super stickies in 5k. These angels look like they will go for about 8k

Don't ride with a tool bag batabing.

Dam, why didn't I think of that

Witch reminds me. It hurts when I do this any suggestions?