Has anyone ever had or seen a Fat Boy go into a headshake an tank slap? I am just trying to figure out why?

 

Not a Fat Boy, but I've had my Sloptail in a couple.

Reasons: Bad tire, neck bearings worn or out of adjustment, wheel bearings worn or too much end play, wheel bent, wheel-tire out of balance. Do a search of this site. I know I stuck a front end adjustment procedure in here some where. Doesn't cover the setting of front wheel end play, though. Get a manual for your bike and check it.

 

Actually, the problem can no longer be fixed. It was a stock ’02 on Demo from the dealer. It happened at 50 mph. Nothing obvious like a flat. I watched it happen.

 

Can you describe what a headshake and tank slap is?

Also, can it no longer be fixed because its beyond repair or do you just mean that you dont have the bike?

 

Head shake is when the front end starts rapidly and uncontrollably wobbling at a high rate from side to side. Tank slap is when the head shake becomes so great that the forks are oscillating from fork stop to fork stop, and the handlebars are nearly "slapping" the tank. Usual result is falling down, which might be another way of "tank slap"!

 

The problem can’t be fixed because the bike crossed the centerline into a ¾ ton truck at 50 mph. I was just wondering if any one has heard of issues with a Fat Boy. There are a lot of things that will affect any bike. With trail at 5.8 inches it should be very stable.

 

I have heard of that kind of wabble from a bad front tire, not neccessarily on a Fat Boy.

 

I think Skip pretty much nailed it. Everytime I've ever heard about a "death shake" it has been on a bike with one of those conditions. I have heard that it's pretty normal for the neck bearings to be out of adjustment on new Harleys. A friend has an 05 Heritage like mine. He took it to a local guy to have his front end chromed and he found it was very loose. I'm going to have him check mine...

Ryan

 

...........The problem can’t be fixed because the bike crossed the centerline into a ¾ ton truck at 50 mph


OUCH, but at least it will not do it any more, hope nobody got hurt.

Just another unsolvable problem with these tractors like the cam chain tensioners, When is the MOCO going to stand up to and address these problems instead of denying them. They have been documented by law enforcement organizations that no longer use harleys in their fleets.

 

Actually He died instantly on impact.