Nope, john didnt put the camera in until after lunch.

Of course not..

I think I will invest in a helmet cam for Sandblast.

a few more photos:






somebodies ball joint looks fubar in this shot:

ok, well I don't seem to be able to post pictures anymore. can someone fix those links up there? I tried everything I could think of but no luck.

I just moved them to our own directory...the BB doesn't allow parameters inside of image URLS...ie anything with a ? in it.

Crazyswede wrote:a few more photos:



somebodies ball joint looks fubar in this shot:

Yeah, I was gonna say... "man that right front wheel has some wicked tuck..."

Crazyswede wrote:somebodies ball joint looks fubar in this shot:

Luke,
You've probably already thought of this but the conversation hasn't gone there yet so...
The ball joint failure suggests you hit the bumpstop. Yes?

1. One way to look at that is to figure the spring rate and/or ride height was too low for this particular rally/stage/yump.

If you look at it that way and decide to raise ride height and springrate, you have to accept that it can have a negative effect on your handling and stability. As a racer, I understand how this may not be acceptable to you.

2. Another way is to accept that sometimes you can take a particularly hard hit on a single wheel that just completely overcomes your springs and shocks. If that rock coming off the yump was the culprit, then that's basically what happened I guess.

Going with that reason however, means you've come to a point where you have to decide if you want your ball joint to break first, or your A-arm?

If it were me, I'd much prefer to use the ball joint as a "fuse" than the A-arm! The ball joint is a three-fastener fix and as shown by the photos, doesn't always break "all the way". That allows you to finish the stage and not have to deal with "floppy wheel" syndrome.

Of course, you could always put a lot of TEM (time/effort/money) into developing a "soft hit" hydromechanical bump stop... Similar to a tiny little Mtn Bike shock mounted in place of the rubbers.

Also of course, I literally have no idea what your current bump stop setup looks like. I only know what the stock ones were. So, I could be talking out my ass and not know it until the stink comes back at me.

Luke and I talked about some ideas. He has that cool Jag ball joint with bolts on either side of the ball. That will help with some of the loading. Plus the car really needs progressive rate springs. And he is only running a 60mm bump stop and is thinking about getting some longer progressive ones. I think doing all 3 of those should really help a bunch.

Geoff wrote:Luke and I talked about some ideas.

Yup. Just as I thought...

formulasaab wrote:You've probably already thought of this

Stefan,

I definatly agree about the spring rate part. I am very hesitant to go to a stiffer spring on gravel. A spring in rally is always a compromise, must be soft enough to provide good grip on small irregularities and firm enough bottom on only the hardest hits. The problem is we have got much faster and we are just hitting things harder than before. Thats where a progressive spring would be ideal, unfortunatly true progressive springs are very expensive.
I have always worried about the integrity of the upper ball joint, which is why I had a jaguar ball joint already sitting on my workbench.

My thinking is that if I make a couple design changes such as: stronger ball joint system, longer more progressive bump stop and maybe a slightly stiffer spring I should be ok, hopefully.

-Luke

Luke wrote:Thats where a progressive spring would be ideal, unfortunatly true progressive springs are very expensive.

Even for the coil-overs? Hmm. I wouldn't have thought. But then, I've never looked. It's probably the long-travel thing. "Lowering" progressive rate springs are probably cheap as dirt.

How about stacking two (short and cheap) different rate springs on top of one another?

I put this little stage time comparison together. It show Luke and John's time in the car VS my time on the bike VS the fastest bike VS the fastest car. the stage distances are on the top....the bikes did not get to run all of the stages hence the " - ".

I really liked this image so I bought the full sized version from Pete, figured it would be a good one to use for sponsorship packets and stuff.