beidle99

iTrader: (9)

Ill be starting my build on the b5m lite this week. I know the bearings were in question for the original kit. I see the lite comes with upgraded bearings, are they any good?
Also has anyone tried removing the seals or at least one seal for the transmission bearings since they are not exposed to the elements to free up the drive train?

Socket

iTrader: (61)

The lite bearings are certainly better. I would recommend you pickup a set of the avid or schelle transmission bearings before the build if you're at all wanting a freer drivetrain. I would also pickup several idler gears, and find the one that is the most round.

Jpdanger

What good is upgrading the transmission bearings if you're not also upgrading the wheel hub bearings?

Matt Trimmings

iTrader: (170)

It still frees it up. I would only run the ceramics in the trans and keep the regular bearings in the hubs as they are exposed to the elements. I clean out all the "lube" from the hub bearings and use my own. Not as free as ceramics would be but it makes a difference.

Wildcat1971

iTrader: (84)

I have been running the avid revolution ceramics in my front and rear hubs for a year. still super smooth. I was told they would not last as long, but they have. But we have very low dust here.

Cpt.America

iTrader: (52)

I only run my cars in blinky, so I no longer run any dynamic timing in my ESC. Back in 08/09/10ish... before the blinky mode thing became law in the RC world for stock racing, and when I was running touring car, you had to be VERY good at understanding and implementing dynamic timing in the ESC in order to be competitive. If you want to learn how that all works, do a google search or send me a PM and i'd be happy to explain it.

Having said that, if you ARE running blinky mode rules, you can't set even static timing in your ESC anyway. But for all intents and purposes, adding 10 degrees of static timing in your ESC is no different than adding 10 degrees of static timing to the endbell of the motor.

The real question is when do you gear up or down, vs adding or removing endbell timing on the motor. For your average racer, they really can be thought of as being synonymous. Adding timing feels, for the most part, like gearing up. Now, there are actually differences. Certain motors will perform better, or feel better, or seem to prefer a certain range on it's timing endbell. For example, on my Fantom motors I run in offroad, The motors feel better geared up one tooth, with the timing kept relativly lower, around 40 on the endbell. Geared down but running 50 on the endbell (which should net the same basic power band), feels different... feels like I loose some of that middle power band grunt. It will require testing with your specific motor.

All in all, the rule of thumb, is run your endbell timing to match the size of the track. 40 for a smaller track, 45 for a medium track, and 50 for a large track (just a general recommendation, YMMV). The longer the car spends it's time at max speed of the vehicle, the more endbell timing will help.

beidle99

iTrader: (9)

This is going to be an indoor carpet offroad car, so I will look into the Avid ceramics. Thanks for the advice.

Socket

iTrader: (61)

Leverage and drag.

BrandonBreh

iTrader: (2)

Good info! Thanks! Now what's the difference between running a 69/31 vs 81/27. I guess this goes back to gear ratios and everything, but is there an actual difference? Just some extra info, the class is on a small high traction track. Rules are 17.5 motor but you are allowed to run esc timing.

Thomas PA

There's a massive difference between those 2 gear ratios. The 69/31 is a good starting point for 17.5 buggy, while the 81/27 sounds more like a 17.5 short course gearing. 81/27 in a buggy, would accelerate to its very low top speed very quickpy

Cpt.America

iTrader: (52)

Those are two totally different gear ratios. It's like asking "When I drive my full sized car, what is the difference between being in 1st gear, and being in 4th gear"? Totally different gear ratios. Your power band will be at a lower speed with one, and a higher speed with the other. You need to gear your car for it's weight, and track size/lap times.

The question USUALLY asked, is "whats the difference between 69/31 and 73/32?". Same basic gear ratio, so no real difference. The biggest difference, is where it positions your motor in the car. In a MM car, larger gear sets, while keeping the same ratio, will move the motor forward creating more steering.

BrandonBreh

iTrader: (2)

I just used two big difference in gears example to get an explanation on the difference. From what I am understanding now, going with the larger spur/ smaller pinion is going to get my car to it's top speed faster, but the top speed is going to be slower and with a larger spur you need a smaller pinion, thus moving your motor forward to get your gear mesh right, creating more steering.

Another question, i'm going to start out with a 69/31, 40 endbell timing, 0 esc timing. Let's say I need more straightaway speed, what would you look to to change first?

Thomas PA

Whether you want to handle this with motor timing or gearing will depend on your specific motor. So try 45° of timing. Then go back to 40° and go to a 32 pinion and see which you liked better. Remember to always watch your temps when gearin . Especially when gearing up

BrandonBreh

iTrader: (2)

Yep, just ruined a D4 from heat and have a Reedy M3 coming in . I was always pushing my D4 to the limit on my track and it just slowly lost power. It was at a point where people were asking me why my car was so slow on the straighaway Hopefully I have a better experience now that I have a better insight on gearing and timing.

Razathorn

iTrader: (2)

Timing moves where in the rpm range your motor makes it's torque. Lower timing makes more torque down low, where as higher timing makes for more torque at higher rpm, resulting in a higher top speed capability as well. Your timing selection "shapes" your power band.

Gearing distributes the power band, whatever shape it is, across your car's range of operable speed. Gear higher, you will have higher top speed and less torque everywhere.

Static motor timing (or blinky mode) is not optimal, period, but most people run mod motors like this just because there's no need to add dynamic timing (boost) in most cases, and it keeps the power delivery very linear and temps down. Adding dynamic ESC timing is nice when you want to make a slower mod motor faster on a straight away, yet tame in the infield—its almost like using throttle expo, except the power comes on smoother.

For fixed timing classes such as 17.5, you generally give up some punch down low for top speed because that will get you over jumps or keep people off your tail down the straight. This means you adjust timing up from the normal 30º. I found that once I reached a point adding timing, I was getting very little noticeable top speed gain, but temperatures started going up a lot. I backed off until the temperatures normalized well and I was very near peak power. After that, normal gearing changes can be done to for power delivery and heat with the knowledge that your gearing changes will produce relatively small changes in temperature compared to timing changes that can make temperature sky rocket.

For me, I found that 45º was ideal on my d4 maxzilla, and I gear for either indoor or outdoor for my power delivery and top speed. I never get north of 160F, even after running for 10+ minutes, and my car is one of the fastest ones there, clearing everything with ease and very quick down the straight. This is in my RC10 worlds car btw.

Wayne