Terrible Headshake and the solution

[Cdogman]

06 AE

5389 Miles ODO

Stock Tires

Like so many here my bike developed a VIOLENT headshake on decellerating from 45-50 to 25 mph no braking. I dont mean a wobble, I mean it wanted to eject me as I let it grow to see how hard it would shake.

I started going over the changes applied to the bike in the last few days. In the last 7 days

Givi E52 and mounts

Played with suspension

As I am riding my bike in to get new rubber (Pilot Roads) I am thinking about the changes I will make to eliminate it and deciding what makes the most sense to try first.

Turns out the new tires fixed it all (so far) My front must have been badly cupped, the rear was toast

Did have me scared for a minute........ All better now.

I think

 

[mmonroe]

Turns out the new tires fixed it all (so far) My front must have been badly cupped, the rear was toast
I think

As I was reading through your post I was thinking that even with only 5000mi on the tires, that is probably what the problem is and sure enough....

I have had tires that looked good and probably had 20-30% thread left that started handling badly and doing all kinds of crazy stuff. I put on new tires and all of the problems vanished. I am not sure what it is with motorcycle tires and "me" but for me anyway, they usually need to be replaced well before they look completely worn out - even when they are not very old age wise.

Random thoughts..

Mark

Harrisburg NC

 

[Cdogman]

Mine were only bout ummmm 6 months old. Front looked pretty good, but who knows. I replace in sets

 

[dpleogs]

This has been discussed several times before. My 06 also developed this as time went on and it grew worse over time. I have about 8000 miles on the bike and tires. I had the steering head tightened as the dealer said it was a little bit loose. This had no effect on the problem and it appears to be due more to the front tire cupping as it wears. I also have a Givi 52 on the bike. This makes the shaking a zillion times worse to the point it would nearly whip you off the bike on deceleration if you take your hands off under 50 MPH. If I take the Givi 52 off it only shakes a little bit, not enough to really freak you out. When I had new tires I had no shaking at all w/o the Givi 52 on. I would say the Givi 52 along with your tires wearing is the main problem as it is with mine. My solution is to not take my hands off anymore and I'll be getting new tires soon!

 

[exskibum]

OEM tires on my '05 were the BT020 Stones. At 5,100 miles, I noticed that the front was already a bit cupped, but since the tread was still reasonably good otherwise, and since I had just put a new BT020 on the rear, I took off for a 1,400 mile trip (1,100 in twisties). During that trip, the bike started to develop a shimmy (not so bad that I'd call it head shake) and by the time I got home a week later, it was downright nasty. At 6,500 miles, tread was left, but I was amazed at how cupped the front was and put on a Pilot Road. Been running PRs since, and no more problem.

I'm done with Stones. Didn't like the OEM Stones on the XX, and on the FJR, the rear wears quickly while the front gets the worst scalloped cupping I've seen on a tire with as much tread left on it. I probably should have changed out the front and rear OEMs together at 5,100, since they were both done by then.

If your OEMs were Stones, then I think you found the whole of your problem.

 

[Cdogman]

Yea, I had Stones.

Guy at the dealership said "5300 Miles, You must ride that bike hard, they are trashed"

I replied "Yessir"

I also had them check the Stearing Head and it was 5x5. I talked to them about the grease on the final drive. Turns out I was talking to the guy who uncrated it. He marked every single nut and bolt with a marker as he checked it. Also as it turns out he is a bit of an FJR nut and knew what he was doing too. Sometimes it does work out good. My bike is pretty solid and proper thanks to him doing a good job

 

[Bounce]

Yea, I had Stones. Guy at the dealership said "5300 Miles, You must ride that bike hard, they are trashed" I replied "Yessir"

typical dealer BS. he may be basing it on his majority of sales that use it... lighter weight sport bikes.

i don't ride hard and my '03 with Stones had the front seriously cupped at 4k miles with the back gone at 6k miles. i swapped them for other choices and won't have them again unless there's no option and i can't wait 4 weeks for a slow-shipping mail order.

 

[Cdogman]

Yea, I had Stones. Guy at the dealership said "5300 Miles, You must ride that bike hard, they are trashed" I replied "Yessir"

typical dealer BS. he may be basing it on his majority of sales that use it... lighter weight sport bikes.

i don't ride hard and my '03 with Stones had the front seriously cupped at 4k miles with the back gone at 6k miles. i swapped them for other choices and won't have them again unless there's no option and i can't wait 4 weeks for a slow-shipping mail order.

We will see how these Pilot Roads act. No real chance to do much today except ride home in a torrential downpour. I STILL took the long way home though... I think I am addicted

 

[EXPDSGT]

The factory puts a small dot of paint on each nut after they torque it, to show that it was torqued. Are you sure that is not what he meant?

 

[chornbe]

Turns out the new tires fixed it all (so far) My front must have been badly cupped, the rear was toast
I think

As I was reading through your post I was thinking that even with only 5000mi on the tires, that is probably what the problem is and sure enough....

I have had tires that looked good and probably had 20-30% thread left that started handling badly and doing all kinds of crazy stuff. I put on new tires and all of the problems vanished. I am not sure what it is with motorcycle tires and "me" but for me anyway, they usually need to be replaced well before they look completely worn out - even when they are not very old age wise.

Random thoughts..

Mark

Harrisburg NC

Ditto that. Looks like I'm good for about 5k a set on the FJR. I'm going to be trying something else this time. Not sure what yet, though.

 

[squidbilly]

I was coming home from work today and experienced this headshake myself at about 35 mph. It gets worse when I apply the front brake as well. Its funny because I just noticed that my front BS BT020 was starting to wear funny before I left, and I put my top case on this morning for the commute. I wonder if its worse with a loaded topcase and that's why I noticed it. Anyone know the phsics behind that?

I am so glad I found this forum. I would have been at the dealership tomorrow demanding that they go through the front end.

 

[Shadow]

BT020 Stones. At 5,100 miles, I noticed that the front was already a bit cupped,

I don't ride hard but my BT020 front was badly cupped at 2,500 klms (1,500 miles) on my 06 model.

Changed both front and back to PR2 and never been happier.

 

[TechJunkie]

Yea, I had Stones. Guy at the dealership said "5300 Miles, You must ride that bike hard, they are trashed"

I replied "Yessir"

I also had them check the Stearing Head and it was 5x5. I talked to them about the grease on the final drive. Turns out I was talking to the guy who uncrated it. He marked every single nut and bolt with a marker as he checked it. Also as it turns out he is a bit of an FJR nut and knew what he was doing too. Sometimes it does work out good. My bike is pretty solid and proper thanks to him doing a good job

I noticed right away when I took delivery on my 08 that each bolt was marked. Makes one feel warm and fuzzy once the rpms start to climb! :yahoo:

Then again the owner of the dealership where I bought my Feejer also rides one.

Thanks for the info on your tire issue. As mine ages I will be sure to inspect the tires and be aware of the beginning of the shaking you describe. When time comes I will pop on a new set before I have the rodeo.

 

[angus]

I have 8,000 miles on my 020 Stones and bike handles good. Not as good as new but good the front tire is not cupped I run 40 front and rear i will get a nother 1,000 miles out of rear mostly interstate to and from work. I have a new Stone ready to mount. The Metzlers turned to crap after 4,000 miles.

 

[okmac]

I got 8700 miles on my oem BT020's , I changed the set as the rear tire was worn down to the wear marks. I could have gotten at least another thousand or two out of the front. There was no cupping what so ever on the front. I run 40 lbs in the front tire. I then mounted BT 021's and altho they are lasting well I am not happy with the way the front tire wears and wants to fall into the turn. I have about 2 K left on them and I have another set of BT 020 ready to put on. I like them, and by the way I have no cupping on the 021's either.

My .02

Mac

 

[Vacman]

Don't know if it applies here but on the cruiser forum for vtx's we upped the tire pressur and got rid of cupping

 

[HotRodZilla]

I just replaced the OEM Stones on my bike at 5700 miles. The rear was toast, but I was thinking the front looked pretty good. On the way home from a ride, I let go of the bars to adjust 'something', while I was coasting. Got that front wobble pretty good. Decided I should replace both tires. I had a BT021 rear in my garage, but no front, so I went with a Michelin PR I was able to get that day. Saw the wear problems people have had with the 021 fronts and didn't wanna risk it. The shop guy said the front was severly cupped and recommended I run 42 front and rear all the time. I've kept them there and so far it's great. The wobble went completely away and I am at almost 7000 now.

 

[RAVENRIDER]

I've got the same headshake on my 08 and it is magnified by the topcase. While I can certainly live with it, this is the first bike I have owned to exhibit headshake to this degree. I guess you get some bad with the good, and the pros far outweigh the minor cons. I'll up the air in the front today and see what effect that has.

 

[Flyguy]

I've got the same headshake on my 08 and it is magnified by the topcase. While I can certainly live with it, this is the first bike I have owned to exhibit headshake to this degree. I guess you get some bad with the good, and the pros far outweigh the minor cons. I'll up the air in the front today and see what effect that has.

Headshake is quite common on bikes that run similar geometries (SST's & sport bikes). It seems to make them hyper critical of any problems such as bearing wear, soft shocks and tire cupping. The ST1300 is a prime example. It not only developes low speed shakes, it can exibit the same malady at elevates speeds although for different reasons. Topcases universally magnify these issuses and when loaded can promote serious levels of instability. The larger they are and the farther back they are mounted, the worse the problem can get. Manufacturer's are concerned with this to the point that many severely limit the weight that may be used in that area.

Also be aware that while relief may be found in borderline cases by upping air pressures, the trade off is that you may be noticably increasing stopping distances.