ausracer

if i was to go to this track i would start at 30mm rollout and go from there.

Trips

iTrader: (16)

I'd go with whatever the car manufacturer recommends as a starting point. Then I'd see how the car behaves on the straightaway. Come onto the straight like you would in a race, and if the car is accelerating all the way til you let off, go down a tooth and try again. If the car reaches its top speed very early on the straight go up some. You should be able to find the ratio that has the car accelerating almost to the letoff point for the turn after the straight. Once you'er there, clock some lap times with a stop watch, then try one tooth in either direction and check times. If changing in either direction improves your times, go another tooth in that direction until your times stop improving or fall off, then go back one tooth.

That's probably not what you're wanting to hear, but that's how I go about it.

T

popsracer

I know alot of people will disagree with this, but here goes anyways.

Try to find one or more people who are running the same Motor as you are. Find out what Final Drive Ratio that they are running
Spur~Pinion X Transmission ratio = FDR. This will give you a ballpark idea of what to run on your car. From there your on your own.
As everyone else has pointed out, without the Same Car, same Driver, track, Motor, etc, etc. It is impossible to give a more specific recommendation as there are just too many variables to account for.

IMPACTPLAYR

iTrader: (7)

UMMMM... yeah there are about as many ways to get to the right gearing as there are drivers in the A-main....LOL

Personnally I race at 3 tracks, one smallish indoor asphalt, one medium sized indoor carpet and the other a large outdoor asphalt (parking lot) track. I know a god starting point from experience for the first ad last, so I go there and make changes depending on the layout and how the car feels.....

I also have a different theory to gearing than most others, I take into account how the car reacts on the infeild, because if you are runninga track with an average of 24 second lap times you may spend 4-6 seconds on the straight, bt the rest of the lap you are on the infeild...... so where are you most likely to burn up a motor???? I don't know how perfect my approach is, but I can say I haven't been slow enough to be passed on the straight away in over 2 years!!!!

Iso Octane

My car reaches top speed very quickly, and pretty sure well before the first turn after the straight. But, I'm also pretty sure that I'm already overgeared. The motor comes back simmering after every run. Our track is indoor and not quite that big either.

Fastburn

iTrader: (18)

I race on 2 tracks for Touring cars, one is a fixed layout track that is set up the same way every weekend, and the other is a track that every race weekend(2 races a month) is a different design, with no 2 being the same all year.
obviously the weekly track is easy to set up for, because it never changes, it is fairly fast, so lots of gear is fine, but the other track, because of the constantly changing layout is a little trickier.
What I like to do is figure out if I can carry lots of speed through corners, or if there is more acceleration involved. I know that the back straight is the same every week, for it is used for the pits, but the twisty bits can make or break you.
When the track is fairly fast, I can pass anyone, for I run a fast gear, but when the track has slower corners, I sacrifice straight away speed for acceleration, maybe someone will pass me on the straight by a car length, but I will gain a few on them in the twisty bits.
This was my first season of racing at this track, so the first race I went with what Losi suggested, but the following races I had to figure it out for myself.
I just like to figure out how the track itself is, and then go from there, I mean, i dont care if the straight is 200ft long, if its got a wicked infield, ill gear my car down so that im faster thru there, cause thats where you are gonna make your time.

popsracer

Brushes can be a good indicator of gearing. Some motors run hot no matter how you gear them but brushes will usually show signs of overgearing.

I also didn't see any mention of Batteries. How good your batteries are can effect your choice of gearing. Better batteries, more top speed, you now have the option of gearing down slightly for more punch and maybe quicker lap times. Speed isn't everything.

STLNLST

iTrader: (32)

if you've been racing for 8 plus years you should already have an idea of what to run a motor at. Any track that I go to I gear my motors the same everytime and go from there. I may go up or down on the pinion gear depending on the size of the track and the layout. I don't change my spur gears all that often but different size spurs helps to reach a certain final drive ratio if I can't achieve what I'm after with the spur that's on the car. do what works for you.

underdog

I run P2K2 motors in my TA04R on outdoor asphalt tracks. I only run rubber tires, and the tracks I run on have long straights (maybe 100 ft.). I like to run 6.0 to 6.2 overall gearing (93/32 for the 6.20). If I go any higher than 6.39 overall, the motor feels like a real dog.

rowdyrj

iTrader: (1)

Do this with almost any car and you will be fine. Take the number of tooth on the spur gear and divide it by the number of tooth on the pinion. If the number ends up in a 3-to-1 combination then you are in the ball park. Then run the car around the track if the motor is to hot and the brushes are changing colors go down a though.

Get a copy of the manual because there'c a copy of the gear chart which the 04 has. Like someone else stated in this your brushes play a part in your gearing but if you are on the brakes a lot it could give you a false reading because braking adds heat to any electric motor.

Go to the longest straight away on your track if it takes your car the length of the straight to top of its over drop down a tooth or two until you get a good comb of speed and acceleration.

Bob Barry

iTrader: (22)

i can completely understand where he's coming from. i am a long time offroad racer. ive run mod buggy for years and gearing wasnt nearly as critical as running stock touring. now that i have switched over to touring i have seen as many as 8 of the top ten drivers every week running WAYYYYYYYYYY different gear. around our area we have some incredibly fast guys and i noticed that whenever they are in doubt they just over gear it. i dont know if its the right way but no one seems to be able to catch them. i read on another thread that the Monsters liked to be run at 7-7.5 i run my every week in the 5.8-6.2 range and i have insane power. my problem is keeping the power flowing through the turns. i tried running the monster at 7.4 and all i did was burn up brushes.....basically my point is....there is no such thing as a set gearing...i show up and put my car down the same as it was where ever i was last. run a few laps and make adjustments....thats why you have practice and thats what makes this racing.

Bob Barry
Team Hiney