upright clearance

[the weldmeister]

how much clearance between the upright and the inner surface of the wheel would you say is safe enough?

we were thinking of having about 4mm.

[the weldmeister]

how much clearance between the upright and the inner surface of the wheel would you say is safe enough?

we were thinking of having about 4mm.

[Ben C-M]

If you've checked the wheel in all extremeties (full bump, droop, all camber/toe/steer settings) and you have 4 mm, then the only to worry about are your tolerances.

I think 4 mm is a bit too close. If your jig puts it a bit off, deflection of the wheel/tire/suspension components might put it close enough to touch. That being said, in 2005 our uprights were so close to the wheel we had to shave part of the head of the outboard tie rod/toe link bolts and round the corners of our uprights because they scraped the inside of the wheel.

It's all a matter of comfort- If you can jig it well enough and feel confident you've accounted for everything in your checks, you don't need to leave more then minimal clearance; just make sure you check it manually at all settings before you run it.

/Ben

[Dr Claw]

dont forget about bolt clearances too for UBJ's and LBJ's.

also, magic rocks exist. they are sprinkled all over your parking lot and your not even aware of it - sorta like lucky penny's at the mall.

maybe its not a big concern since they dont really cause immediate failure, but you'll see a wear band on the inside of a few of your wheels that you cant explain.

[Korey Morris]

We have a set of keizers with this wear mark on the inside. Our 2003 car had about 0.125" clearance between the brake caliper and wheel so we frequently catch these magic rocks. We had to grind down the heads of the bleed valves on that car.... Ah memories, that was my first job as a freshman on the team!



We don't use the shells anymore, but I don't really think that it is a problem.

[Biggy72]

I'm not sure why anyone hasn't said this before, but your wheels will flex. Some will flex more than others and the clearance needs to account for this. Our keizers last year flexed quite a bit and we ended up with some nice machining because of it. This should become especially apparent if you're running where your tires can get hot.

[the weldmeister]

ok.. so 3mm of clearance wasn't enough...
do you think 5mm should be enough, or should we play it safer? we've got keizer wheels too, and we're a first year team.

having scratches from magic rocks wont do any serious damage i guess, but its not something i'd want happening on my car. wheel flex shouldn't create a problem for more than 2-3mm clearance right?

being a first year team, we should probably play it a little safe. how much clearance would you suggest?

[fade]

whats the predicted camber and toe stiffness of your wheel+hub+bearing+upright assembly?

[the weldmeister]

thats' an interesting question, fade. i really don't know... we haven't yet finalised the designs yet, and i hadn't even thought about calculating camber and toe stiffnesses. can you please elaborate on this, how to calculate it, and what should be a good target?

thanks

[JHarshbarger]

This is said over and over again; if you're a first year team, design to finish endurance. If you design your car at the limit, it will often end in failure, even with experienced teams. And it's not the designs that are the problem (in most cases), it's the fabrication. Build a good solid that will get you through competition and get you experience. Make your uprights, a-arms, and joints solid and experience the whole competition. If you put your suspension together and your wheel doesn't fit over your upright, you've just lost a lot of time and possibly a chance to compete. I would just play it safe and give yourself plenty of space and expect some fabrication/design errors.

Good luck!