Improve speed on flat portion.

[garthbro]

Had a good showing at today's derby - finished second and moving on to the next round. Thanks for all the great advice from the past!

In the races, I observed that my car was clearly the fastest on the downhill but lost leads on the flat portion of the track.

I don't want to do any major work, but I thought I might try a little fine-tuning before the next round in a few weeks. I'm guessing that I'm loosing speed on the flat because of friction in the wheels...thinking I might burnish the wheel bores with some graphite (using extra soft pipe cleaners) and spending some more time breaking in the wheels (didn't get to spend too much time on this round.

Any thoughts? Is this where I should focus my time?

 

[Bullet]

If you are over-steered, you could be losing a bit on the flat also. Not sure what you mean by breaking in the wheels, burnishing bores hopefully, but take all precautions to protect the running edges of the wheels like new.

 

[garthbro]

Should have also mentioned that I designed it to be a 3-wheel rail rider. During tuning, I had a fairly "gentle" bend into the center rail, but to be honest, I didn't focus much during the race on the results or if it was bouncing off the center rail.

I was thinking of burnishing the wheel bores, reinstalling the wheels, and then just spending some time spinning the wheels by hand as I add graphite.

 

[BulldogRacing]

is your weight at the rear? Is it on the hill as long as possible without popping wheelies?

 

[Fumbles]

Is it wiggling in the flat straightaway? If so, I'd imagine it needs more steer as it's getting a good head start downhill maybe due to less steer/rail riding.
If no wiggle then I'd think your weight is good to go as it's getting down the hill first.
My sons car behaved just like yours last year and I never figured it out.

 

[B_Regal Racing]

Not sure what others do (in partcular, the pros), but I have always found that graphite is the fastest after 4 to 6 runs, and then begins to tail after 10 to 11 runs or so. After burnishing and the pledge trick, I would spin my wheels with a drill buffing wheel on low speed to simulate 4 runs. After that, the car should be as fast as its going to go, but it will start to lose speed after 6 runs or so. All this presupposes that the car is tuned to its absolute best.

 

[garthbro]

My weight is concentrated about 3/4" to 1" in front of the rear axle...no wheelies.

Embarrassed that I didn't focus more on how the car was performing during the race, but I don't recall it wiggling a lot...I certainly didn't have my attention drawn to that.

Funny, though, I did seem to notice that the speed was best around races 3-6, and then started to taper off. Wasn't a big difference, but that's why I figured I would simply focus on the graphite.

 

[Pacfanweb]

This is why I wish we raced on longer tracks here. The flat is where our car starts really pulling away. It's great down the hill, too, but IMO it's my son's prep work (axle polishing, Red Rocket, burnishing with DD4H graphite and Pledge) that lets it pull away at the end.

We're on 32' tracks, but the car is steadily leaving the pack at the finish. 10 more feet, and I think it'd be a lot bigger gap.

If you lose distance on the flat, then re-think your prep, and really check your alignment. If you are running the rears canted, and a 3 wheel car, you should be rolling.

As a former NC State receiver said about another of our receivers, who had Olympic-class speed, "after 40 yards, if you're even, he's leavin' " Meaning he was just getting rolling and would leave you in the dust.

That's the way a car prepped the DD4H way IMO should be rolling at your typical pack race. At the bottom of the hill, if you're even, you should be leaving.

 

[plhiatt]

Pacfanweb results are same as mine, really the last 7 feet our cars really pullaway.
I have observed that the difference between graphite and oil on to be greatest on 42'
track as well. On a 35 ft track times are very close, then run same cars on 42' you really see
the difference in oil.

 

[Obsessedderbydad]

Losing speed in the flat portion is usually a sign of over-steering OR your weight isn't as far back as it should be. Basically your potential energy is gone before others.

 

[GravityX]

...thinking I might burnish the wheel bores with some graphite (using extra soft pipe cleaners) and spending some more time breaking in the wheels (didn't get to spend too much time on this round.

Any thoughts? Is this where I should focus my time?

GB take a look a this thread.

 

[Obsessedderbydad]

^ +1, this is what we do. Plus use colored wheels if you can. Yellow or Orange are better for being able to see your burnish job inside.

 

[B_Regal Racing]

^ +1, this is what we do. Plus use colored wheels if you can. Yellow or Orange are better for being able to see your burnish job inside.

Temporary Derailment: Are you racing again? You may not know it, but some of your posts helped me to get going initially...

 

[Obsessedderbydad]

Thanks B. It's all about community and helping each other. While I know I'm no where near as good as probably 95% of the racers on here, I can speak from my own experience and what works for me. I can not confirm or deny that I will be in the March races. I will however post my "possible" new car logo... if I would race in March that is...