Tag Archives: tires

So much done, so little accomplished

I was out of the house almost 7 hours today. I had a 20 minute procedure done in Lewisville and spent just over 6.5 hours getting to and from it. And I had to skip lunch because I was constantly running around to catch a bus or train with never enough time to stop to buy food. So, I had a lot of time to sit and think about things, and when I wasn’t thinking about things I was thinking about my second-favorite subject, the Mid-Bucket.

The big thing weighing on my mind about the bucket is getting rid of its inherent oversteer. There’s just way too much weight on the rear axle for 4 equal-size tires, and not enough tire selection in 15″ rims any more to be able to correct it with bigs and littles without giving up a ton of front grip. While I realize that excessive front grip is the problem, my philosophy is don’t give away what you have too much of in relation, get more of what you don’t have enough of. So, while I’m willing to find larger rear tires to get more rear grip, I’m completely unwilling to get smaller front tires to get less front grip. This is a race car, you always, always, ALWAYS want more, especially more grip. It may be a race car that I’m going to drive to the race and (hopefully) drive home, but it’s still intended to race and win.

Before I get back to the bigs and littles there are ways to keep the tire size “square” (same on all 4 corners) and reduce oversteer without completely killing the front grip. That can be done with restricting wheel travel on the front while getting absurd amounts of travel on rebound on the rear with long travel shocks and bump stops that only allow the same amount of compression as the front suspension, so that as the car rolls over on the outer tires the inside rear tire is still carrying a lot of weight because it still hasn’t extended the spring fully.

Another way is aero loading the rear more. That one is a little more tricky as rear grip will vary as the square of speed, so the car will still be loose at low speeds but potentially plowing tight as the car goes faster. This is not the way to go. Obviously I’m going to go for as much downforce as I can get, but balanced, and after I get the mechanical grip balanced, not before and definitely not “instead of”.

And I keep falling asleep on the keyboard so Nighty-Night…

I didn’t want to do it this way, but I have a working tire pump now.

Well I had two pumps, one that failed somewhere in the piston and the other one that had a rotting hose from the pump to the chuck. I only have to send one back, so I put all the bad parts in the return box and assembled all the good parts into a working pump. I then used that pump to get my tires back up to the minimum 70 pounds per square inch to prevent pinch flats on potholes.

And after I did that I felt like Superman™ so I tried to mount the tires to the wheels I had just mocked up that afternoon. It was a struggle, but as you can see:
Wheel reduced from a scale 10 inches to a scale 8

I got the front edge even with the bead on the tire, but I need to pump the tire so the back side matches the front.
Back side sticks out a little bit, don't it.

It’s hard to see from that angle, so this is easier.
See all that white? Not supposed to be visible.

So what I do now is talk to my diabetic friends about getting some used needles and syringes to pump up the tires to meet the beads of the rim.

And there’s something good coming on Science Channel, so I have created enough with the words and pictures, Opus the Unkillable