Artificial-I

iTrader: (17)

Just to make a little point. The more you lighten your drivetrain , the less traction it will get in low traction situations.

Same goes for cars or motorcross even. When your not getting grip out of the hole we will usually run a heavier flywheel. Which is the same as running heavier driveshaft components.

So its not 100% the best idea to just lighten your drivetrain.

But on the flip side a lightweight suspension is a good choice in almost all situations. Reduced unsprung weight helps it cope with bumps better. Therefore more grip.

So TI pillow balls are a BIG #1 choice for me. I got those on for sure. As they are at the end of the arms , this will help your car absorb bumps more efficiently.

itchy b

iTrader: (2)

The mess is indirectly caused by the Sirio( plenty of wheel spin! )

MaDaGAS CAR

got my mugen mtx4 wce yesterday and from wat i could see there was not a big diffrence between the normal version and wce but im yet to compare the 2 next to each other cant wait for the maiden voyage

Bigbarn

iTrader: (13)

Yes, lightening your drivetrain will cause you to change your setup. This is true.

TomB

iTrader: (10)

dude i htink you are wrong. a lightweight transmission on a car is beneficial especially when the engiens we use rely on rpm to produce power. Your example of a motorcross bike is wrong to apply to a rc car. why? because a flywheel on a motorcross bike is on the rear wheel. you are getting more traction not due to the heavier flywheel, but due to the added weight on the rear wheel which acts as a lever pushing the tyre down more (ie imagine accelerating a bike as 5 guys push down on the rear).

guys, a lightweight drivetrain is the best modification you can do to a car. Remember that these engines rev upt o 41K + so therefore the quicker you get it up to it's peak rev range (whatever it may be...20,000 to 30,000, or whatever it is) then the more punchy the car will be and the better power it will have out of the corners.

a lightweight drive train does not make the car less grippy, this is a falacy, that originates from a bad example (ie motocross). a car that is close to minimum weight will wear out the tyres less (to an extent) use less fuel (to an extent) place less strain on the engine (to an extent) and will be more punchy out of corners.

drivetrain mass i remember someone saying here ages ago, is equivalent to x2 static weight (or something like that) basically what i am saying is that rotating mass is x2 more important and worthwhile eliminating than static weight.

artificial your comment of pivot balls being better to lighten goes against what you said about motocross bikes and your flywheel example. ie, if your flywheel motorcross example was correct, then the heavier pivot balls would also seem a better option if we continue your analogy. ie more weight then on the ends of an arm, according to the motocross flywheel principle would be better as it places more downwards force on the wheels, hence more grip right? BUT OF COURSE THIS IS WRONG! reduction of unsprung weight is important, and so is rotating mass.

experiment by drilling holes in a flywheel (ACUARATELY!) and you will eventually find the maximum you can drill it out to without affecting idle. this is the lightest the flywheel can go without ruining the idle...done problem solved, and fallacy of a heavier flywheel is good analogy solved!

remember these are not drag cars, or motocross bikes, two things that require and rely on weight over rear wheels to lay down power effectively.

Tire Chunker

iTrader: (16)

Thinking about trying my old Mtx-3 H710 clutch bell with the Mtx-3 .08 pinions to stop the spur gear stripping problem?

What do you think? Three years of racing this car I never lost a spur gear, the mtx-4 and 3 use the same spurs and other centax clutch parts it seems like it might be a good fix. I might also try the larger pitch spurs and pinions I also have from the mtx-3.

Nitrogasm

question about set up

if the set up sheet calls for 2 degrees of rear toe in
is that 1 degree per side equaling 2 degrees or does that mean 2 degrees per side ?

i am using a hudy set system and i have been using the set up sheet as per side , but now im thinking i have been doubling my toe in settings .

can someone enlighten me

cheers

Andrew D

It means 2 degrees on each side

twoh

I was building my new MTX4 kit and came across a problem I cannot seem to solve.

When I put the servo steering linkage on the servo it rubs the servo. JR 9000S.

When I put it on my KO it rubs that also. I am not sure how mugen wants this mounted. The way it is pictured in the manual it should be perpendicular with the servo when centered.

Any help would be great.

Bigbarn

iTrader: (13)

Everyone I have ever talked to about rc racing says lightening the drivetrain is the way to go. The lone decenter is AI. I like the explaination that followed from TomB. Drilling out the clutch shoes is also important not for the weight issue but for more consistant clutch engagement through corners and slower sections of the track. However this must be coupled with a really hard spring.

lil-bump

iTrader: (89)

Make sure you are using the correct servo spacers.

Artificial-I

iTrader: (17)

Ive heard the same too for years and as far as acceleration on a grippy surface is concerned....its correct. Otherwise low grip...no. Therefore I wanted to have the full statement , not just half cause it doesnt work in all situations. Hearing something doesnt make it true either.

I just got tired of hearing it over and over in this thread without both sides so I figure I would share some of the real benefits it has and in what track conditions.

Otherwise where I run...its not a benefit. Low grip tracks , its not a good idea to get a setup thats easier to spin tires.

JetMD

iTrader: (1)

I've been messing with my steering servo lately so I feel your pain. The servo horns that come with JR servos will not work. I installed my JR servo and came across the same thing your are talking about. The horn simply fits too close to the servo case. You'll need to find a aftermarket horn. The one I used is an older version of these. You will need to do some trimming on either of these to get maximum steering throw. I trimmed a little on mine to keep it from hitting the battery and I had to trim a little like the picture in the manual shows (where the ball-end hits the horn).

http://www2.towerhobbies.com/cgi-bin...&I=LXHZE3&P=SM

http://www2.towerhobbies.com/cgi-bin...&I=LXLMW2&P=SM


I personally think the JR horns aren't "beefy" enough. When you drill out the hole in the horn for the screw, it gets very thin. I would be concerned about the arm breaking. Hope this helps.

Artificial-I

iTrader: (17)

So today I took the car out for the maiden run at the track. The car is pretty good on the track. Turns well , has pretty good rear traction, even though its the first time hitting the track.

Well the car was shifting well and after awhile just kinda stopped shifting into 2nd. Which is odd as my friend has the same thing he just says , it shifts different everytime. That wasnt so nice.

I was also having some motor trouble , then finally got it to stay running. Then im running around and I didnt even hit the wall hard when my right rear wheel start flopping around like a useless limb.

Pull it in and its got a broken hinge pin/suspension shaft , broken arm , stripped ball holder. I then talk to one of the guys on the track and hes like man , my RRR never really broke anything for the last year.

Im like me either, I never broke my r40 like that except for one time at the end of a straight I took the turn way to fast and smacked the wall. I go into the lhs and my friend who also runs a mtx-4 says hes never seen that on his car.

Either way pretty bummed. Bad shifting , bad motor and broken parts they didnt have to replace makes for no racing tommorrow. Im gonna try to retrofit some parts. But has anyone had any problems such as this. I now know im getting the hardened hinge pins for this car. But im worried about the arm and how it just ripped right through it.

I think I might know what to do with the 2 speed. But the arms breaking and shaft and such at such a low speed is kinda making me think. Im hoping its just a fluke.

But the spur gear looks great. I think ill never have a issue (crosses fingers).

Let me know what kinda stuff you guys are breaking and what you did to prevent it.

EVIL-ET

after breaking a few rear arms, shock shafts, swaybar links, rear bulkheads, rear shock tower, rear hinge pin holders and bent hingepins.
i found the best prevention is not to hit hard objects, so i haven't broken any of these parts for awhile