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First off I'm OK I'm standing at the side of a road waiting for the RAC which I've just joined. Was a nice day so thought we'd go out do a bit of filming and take some photos. Towards the end Richard was filming me doing some drive bys. Went down the road to turn round came back. All of a sudden crash and my from passenger side wheel is floating about. I thought the wing had come off but no, lower wish bone has torn in two just behind the ball joint.
I'll post some pics went I get back got some video as well but I'm not sure you can see much.
What happened? Wishbone just gave up the ghost????
There's a triangle metal bit that holds the ball joint its torn straight across where the weld is and over the metal. Looks like a material defect on initial inspection. I'll know more once I get it in the garage and the bits off.
Still waiting for the RAC man at the moment. Lucky I'm not too far from home.
he he I've got once of those pocket pc phone things (and a long cable ) took forever 3 blocks of wood and a trolly jack to get the car on the truck. Nice bloke though from the towing services.
Here's some photos, lucky there was no one else involved and it was on a very quiet B road:
First thoughts are that the metal plate does look a bit thin for such a job and that I would have thought it a better idea to extend the tubes to just after the central pivot point of the balljoint. I'm certainly no engineer though so could be talking boswollox.
Very sorry to hear about the crash but the important thing is that you are ok.
I agree with John that the metal plate doesn't seem that well supported (i.e. cantilevered off the wishbone) and the welding may also have weakened the plate leading to fatigue. Extending the wishbone tubes further out (like they are on the top wishbone) is a good idea.
Are there any signs of fatigue/cracking on the other side?
I wonder if anyone else has had the same problem.
Also, it will be interesting to see what Marlin have got to say on the matter...
Thank goodness that you weren't going at speed or on a motorway! It looks like one of those F1 photo's when the wheels come off.
Good to see that your brake pipe styed intact.
Isn't this the part that had changed on Jason's kit (GOO's)? (remember he had to modify his bolt head to fit)
Is there a hint of rust on the crack (photo 4) suggesting that it cracked a while ago?
As others have said, Marlin's response will be interesting. (Might be worth contacting the MOC as well to see if anyone there has heard of this before.)
This would surely be a recall on safety grounds for inspection and replacement?
Thanks for all your kind comments guys I've posted on the MOC forum too see what they say.
I'm going to take things to bits either after work this week or next weekend see if I can see any more. In the meantime I've posted another thread with the video from before this incident!
Good news spoke Mark. I'm sending the lower wishbones back to him to inspect and he's replacing all the parts for free that have broken! He's not see one fail there before so I'm hoping it was purely a weak piece of metal or weld.
I am worrying about mine now, since they are exactly the same construction as yours Patrick. I've noticed, that compared with some older pictures, the damper mounting plates on this type have been extended out towards the ball joint threaded bush,which makes the rest of the wishbone plate very stiff. The line where yours has broken becomes the weakest point.
It will be interesting to see if Mark modifies this area on your replacement parts.
I'm not sure how best they would be inspected. I think race teams X-ray their parts before use.
Given the Sportster has been on the market for 10 years and (so far) mine seems to be the only one that has had this fault I'd put it down to either weak material or a dodgy weld rather than a serious design flaw. However it does expose the weakest point of the design.
peterux wrote:
Any other parts bent or damaged?
Peter
Track rod & head lamp casing. Need to take more off the car before I can say for sure.
Glad you're ok, and Marlin have sorted you out with replacement parts. My lower wishbones look like this:
The only thing that seemt to have changed between Patricks (and the rest of yours) and mine is that the damper mount has moved from the top of the plate to the inside of the wishbone.
That looks substantially stronger in the area where mine broke!
Mark was also talking about the angles of the wishbones and track rods saying that steep angles are bad. He wants a picture of the front of the car with it sitting on the front so he can see what angles things are at.
I think as Simon suggested, if the tubes were longer like the top wishbone, there wouldn't be a problem becasue the ball joint would be welded to the tubes rather than just the thin triangular plate.
Alternatively, an additional plate welded across the bottom of the ball joint socket and the lower edge of the tubes would add strength with only a little addtional weight.
I'm standing at the side of a road waiting for the RAC which I've just joined. Was a nice day so thought we'd go out do a bit of filming and take some photos. Towards the end Richard was filming me doing some drive bys. Went down the road to turn round came back. All of a sudden crash and my from passenger side wheel is floating about. I thought the wing had come off but no, lower wish bone has torn in two just behind the ball joint.
) took forever 3 blocks of wood and a trolly jack to get the car on the truck. Nice bloke though from the towing services.
