front end "tank slap" issues at triples

[SethO]

I have the new update and mine still hits 120 on the speedo with the wheelchair on the back so.. I still have the side to side tank slap issue, even with brand new OEM tires at 22 psi. had them at 30 psi too. Right about 106 on the speedo (100mph real speed) I get side to side tank slap that started to happen about 11k, thought it was my front tires which were worn on the inside which I rotated so I assumed it was chop of uneven tires but got new tires a few days ago with the update and it hasn't tripped the VCS relay which I have to get off, put my wheelchair together open the boot, push it down in the fuse box and get going again, I ordered another relay but they gave me the wrong one.

If you don't drive you spyder this fast and are not comfortable DO NOT do it, I am a firm believer in the saying "ride your own bike" you can't keep up don't and if you bored out of mind speed up.

The reason for the above statement is that I want input on people that done this kind of driving on the spyder, and I will put the statement "if you don't drive your spyder that fast you would not notice it" there its already in the thread so no one has to drop that feel good comment.

I did forget to as doc about this issue at BIR and I am kicking myself for it.

 

[Firefly]

Can you better define what 'side to side tank slap' is?:dontknow:

 

[SethO]

tanks slap is side to side play in the handle bars,in a real bike it happens when you put a wheelie down and the front tire isn''t straight. the tire(s) are jumping side to side, the front end is "floating" it has been more of problem since I have the front end suspension tightened all the way up, I was going to step this down and see if it help, which does not make sense to me because tighter would give less play.

 

[Firefly]

Hmm. Not sure why they would call it tank slap.

Anyhow - I've never felt this on the Spyder- and have been 100+ many times.

I would think tighter suspension and more tire pressure would cause MORE of a bounce with this kind of suspension and 2 wheels.

 

[effgjamis]

I, also have not any symptions of " tank slap " and following doc at 90-105 across country surely would be an issue.. But No Issue. As it is smooth...

 

[spyryder]

Oh ya, those 500 Kawasakis from the 70's were real tank slappers.....or "speed wobble" was another popular term.:f_spider:

http://en.wikipedia.org/wiki/Speed_wobble

 

[BajaRon]

If you're getting a speed wobble something is definitely wrong. I've had my Spyder to 120 on the speedo. Rock steady, as it should be.

 

[bone crusher]

I used to have the front tire pressure at 20...I felt the ride was too hard...at 18, the bike is much happier...as far as the back tire goes, 28 is good for me...

I think many like to jump the pressure up a lot but I find it makes for a bumpier ride...

 

[gazey]

Might have something to do with the wheel chair

SethO it might be something to do with the wheel chair on the back. It might be affecting the areo dynamics of the bike and be lifting the front at that speed. Or maybe the extra wight over the back wheel. There is a switch in the seat that changes to stability program for when there is a pillion on the back. You might be able to set this switch somehow so the bike thinks there is someone on the back and see what happens.

 

[SethO]

I will try to drop the suspension down softer, it sticks night and day different with it stiff so it is annoying that it has a problem like this, if I hold it tight then it powers thru and is not as bad at 115ish.

 

[Firefly]

How often does one really go over 100 mph where this would be a concern?

 

[aka1004]

i see i am not the only one with front tires wearing out only on inside...
my dealer does not know what's causing it.
may be it's the ken's sway bar + aggressive ryding habit:dontknow:
i did not notice them wearing out on inside till recently (at 21k miles right now) and i did not have ken's sway bar till 13k i think and at that time front tires still looked good without any uneven wear.

i guess i will just have to rotated them.

 

[bone crusher]

I will try to drop the suspension down softer, it sticks night and day different with it stiff so it is annoying that it has a problem like this, if I hold it tight then it powers thru and is not as bad at 115ish.

Seth,

Can you get assistance at the track and remove the chair? Then obviously have someone help you when you're done? This might help drag a little...

 

[bone crusher]

i see i am not the only one with front tires wearing out only on inside...
my dealer does not know what's causing it.
may be it's the ken's sway bar + aggressive ryding habit:dontknow:
i did not notice them wearing out on inside till recently (at 21k miles right now) and i did not have ken's sway bar till 13k i think and at that time front tires still looked good without any uneven wear.

i guess i will just have to rotated them.

You think the swaybar is toeing the tires in more? Anyone else having this issue? I didn't think that the toeing was affected by anything like a cross stability bar??

Also, where is your tire pressure? I think those keeping it at 20 might have faster wear...I dropped my front tire pressure to 18...more comfortable ride and the bike seems to stick more to the road...both good things!

 

[BLACK WIDOW]

100 mph

How often does one really go over 100 mph where this would be a concern?

:agree:

 

[Firefly]

i see i am not the only one with front tires wearing out only on inside...
my dealer does not know what's causing it.
may be it's the ken's sway bar + aggressive ryding habit:dontknow:
i did not notice them wearing out on inside till recently (at 21k miles right now) and i did not have ken's sway bar till 13k i think and at that time front tires still looked good without any uneven wear.

i guess i will just have to rotated them.

I had them wearing them on the inside also - at around 8,000 miles - so I had them rotated to I can even them out. Only recently put the sway bar on - so I doubt that is the problem.

If you're getting 21K out of a set of front tires you should be thrilled. I got 8K out of the rear and doubt I'll get 15K out of the fronts - but those numbers are really good for a motorcycle.

 

[aka1004]

my first rear tire did not last long but i am taking it easy on this kumho and it's holding pretty good.
i suspected sway bar because i did not see uneven wear on fronts before i installed it but if yours had uneven wear may be not...
i think i may have another 10k or more on front if i rotate them.

 

[DannyS]

I did not have uneven wear before or after the swaybar. I also did not have "tank slap" before or after the swaybar(tat the speed you are talking about. I do have chatter left to right when on rough roads but from your description I don't think that is what you are referring to. I can think of two things that would cause this one is alignment (or tow)which would match the inside tire wear also. The other is one bad shock that is ending up with different rebound or compression than the other. It could also be unmatched springs but that usually means difference in right and left hand turns or pulling.:dontknow:

 

[Tom in NM]

How often? Just once.

Seth, I was concerned (given my experience) that the software update would have slowed you down and I know you would have been very unhappy with that.

On my one 120 mph experience, no handling problems, outside of the expected from the general condition of the road surface. Nothing like you describe.

I did find myself going around 100 the other day ( Black Widow's I40 Racetrack ) but, I did not notice any problems in stability or handling. My BMW F650GS starts showing some instability just under 90 mph sometimes.

My tires are one to two pounds over recommended, shocks on 3 (firm for a 145# guy riding alone on a stock SE5) and no sway bar.

Tom

 

[SethO]

How often does one really go over 100 mph where this would be a concern?

maybe read the the first post in this thread, I hit triples everyday I ride, this not a internet tough stuff comment but a true statement. Some days more than others, depends on the weather and how much time I have. IF YOU don't go that fast, good for you do with you spyder what you will, if you have personal expirence on this issue drop some of it on us.

the one bad shock issue makes sense, DOCDURU replaced his shocks and I had talked to him about it.