New Zz Pcb Mod
 

This is the mod we have all been looking for. As always use at your own risk....if your ZZ blows up....dont blame me.

there are two 68 ohm resistors that will be jumpered. Locate these resistors as follows:

1) Remove the clear cover over the PCB.
2) hold the ZZ so the motor is on the right.
3) on the PCB there is a very small resistor on the very bottom right corner just below a 3 pin MOSFET (labeled Q6). Solder a jumper across this resistor.
4) locate the same resistor just below Q5 and jumper it.

5) In summary you are jumpering the two resistors just below Q5 and Q6. Note: between Q5 and Q6 there are two resistors the one you are jumpering is the top one (the one next to Q5).

Based on test myself and others have done we know that the speed controller has a very high on resistance. I originally thought this was due to poor components etc. I now think that the speed controller is designed to not allow full current to reach the motor. Not sure why, but it seems that way.

This mod allows forward and reverse to work and boosts the current supplied to the motor by 25% from a somewhat charged battery of 1.22volts before the mod I saw 97ma after I was getting 125ma. A fully charged battery no doubt would bump the current more.

I would caution against running multiple batteries with this mod.

Cheers

Faster?
 

Likely much faster, eh?

Possible for you to post some pics of the process?

Thanks for the tip!

Sounds like my kind of mod. I dont really like the idea of adding batteries. I got my parts car and a soldering iron. I get back to y'all in a few with my results.

I'm adding this gem to the 'Look here first' sticky!

Good stuff gpile, thanks!

so how much improvement on the speed is there? can you tell the difference, or are you just saying the power is better according to the meter readings?

pictures of this would be awesome i definitly want to try it, but would love a pic or two to go by

I am in the process of compiling a big giant FAQ about Zips, which will be posted sometime probably late this week or early next week. I hope to have a central repository for ZZ questions.

If you could provide a labeled pic, I would really appreciate it, as I am sure everyone else would.

Regardless, thanks a bunh for the info!!

How do you solder a jumper? Never solder before but I would liek to try soemtime and tips for a newbie?

Nice job!
 

I just did the mod. At first I thought you were trying to tell us to jumper the two resistors together, which didn't make sense. Then I realized that you BASICALLY wanted us to bridge each resistor together (seperately).

I was thinking of just removing the two resistors and running a layer of solder between the points, but took the ghetto way instead and just put a big amount of solder between the points (on top of the resistor). If I want to remove the solder later I can use a wick or suction.

On another note, you might want want to include the resistor numbers along with the location (ie, R19).

I also found out that the two MOSFETs on the right side of the board are paired with 2 resistors each. One set of 2 resistors and 1 MOSFET is for forward controller, the other is for reverse... very interesting.

EDIT: I assume you CAN run multiple batteries, just in parallel, just not series. Also, I think the reason the resistors were put in place was to allow for longer runtime. Since more maH is going to the motor, the runtime is shorter. So if you add a battery in parallel to the existing one, the runtime should be normal.

Thanks again for the mod tip, works great!

Matty,

Feel free to add upon the FAQ I already have (in my Sig)...No need to redo what's already done, but I'd love to see the FAQ become more comprehensive!

Re: Nice job!
 

I tryed running two batteries in parallel. you lose all reception to the radio.

Re: Nice job!
 

So, for those of us waiting for results before we do this, how did it work?? Big improvement? Not that big? We need details!!

... the details.
 

Well, the mod worked out well. Here is what I found out through driving it around for awhile:

My Car: Green Gearing, Turbo (RED) motor, stock battery, stock body.
Co-Workers Car: Green Gearing, NOS (Orange) motor, stock battery, shaved body w/ drilled holes in chassis to drop weight.

I took both controllers to get a even drag start and notcies my car was now MUCH faster than his right off. I was actually beating his NOS for about 5-8', then he took over and won. I was VERY happy. This was racing a NOS vs. Turbo motor AND more weight on my end (stock body). I then had him do the above mod and raced again. This time we were dead even at the start for 5-8', then he continued to pull ahead.

This shows there is some extra speed from the start, but in the end, the motors higher RPM/top speed pulls away. I also think with this change, you can't really "beat" other people.. I consider it a 2-3 second "advantage" when racing those who don't use the this mod. Also, it seems all people with this mod will get the same quick start as others with it, ie: independant of gearing, motor, etc...

The downside... this eats my battery QUICK! Every 1-2 minutes I need to recharge. I really think the manufacturer added the resistors to increase the runtime.

Overall: A nice mod.. it has its place in certain races, but given the amount of runtime between charges I get, I'm not sure I want it all the time. This is just my PERSONAL opinion though.

If I don't see any pics from gpile tomorrow morning, I'll scan my car and post some pictures of the mod for others to follow.

OK here's a diagram for the mod. Sorry about taking so long....got to work and pay the bills etc. You are basically jumpering or putting a blob of solder across each resistor (not connecting them together as others have indicated).

Gomer

Sweet, I'm all over this as soon as I get home this weekend and have access to a solder gun.

Thanks for all the hard work and info guys!!!

<IMG>This Bud's for you!

hi guys,
are you guys talking about the microsizers. i can't seem to find these resistor you are talking about. what is a zz.

You're in the ZZ (ZipZaps) subforum bud...This is NOT for Bits/MicroSizers.

I did it with NOS and the red gears. Nice. I'm gonna see if it can power my MS 2.6 now. IT couldn't before.

Powers the 2.6 effortlessly with a stock battery. Runtime is reduced severely with the NOS motor versus the resistors not being jumpered, even more severely with the MicroSizers 2.6 motor, but damn the 2.6 is fast now. Before this mod, I could only "rock" the car back and forth about 1/2 inch with the 2.6. Now it takes off.

Two Thumbs up. Also, I can't think of a reason I'd need excessive runtime of over 2 minutes. I don't mind charging it every few, as long as I can make a run through a large autocross course or make a drag race run I'm happy. My batteries aren't fully charged so I'm in no position to give you a runtime breakdown. It seems like about a 50% drop in runtime, longer than 2 minutes but not by much.

Just an FYI - Put the Control or Performance motor in and I bet you'll get good runtime. This is a lot like tuning real cars. You put a turbo, exhaust, headers, ported/polished head, stroke and bore it, and then you go out driving like a maniac, your fuel economy will suck. I wouldn't expect any different with what we're doing to our Zaps.

do yall think it will run the 3.8 and is there any reverse side effects ??could i take the soldier off and will it go back to norm ???thanks -cat-

I have a 3.8 on order. I'll let you know when it gets in. This isn't a mod for people who are new to soldering though. REMOVING the solder will be even more difficult, but in theory it should be back to normal when you remove the excess solder, as long as the surface mounted resistors will stay put!

so can we get a def. way of doing this ???cant you just remove the chips and soldir a line in place ??

Interesting thread. How does this compare with a ZipZap with a Microsizer/Bit circuit board? That's what I run in all my Zips. I'm curious if this mod makes the Zip board pump out more juice to the motors than an bit board. Can someone test out the readings?

Thanks
nugz

well idid it. good results the only thing is that i hate soldering and some how the resistors came off while i was bridgeing them together well twenty minutes after i charged up i am still running strong well what is wrong do i need to put the resistors back?

Good job Oz. That sounds like a good idea.

Welcome aboard crazy foo!

hit me up on AIM if you see this. Maybe we could post some pics too

Re: New Zz Pcb Mod
 

I assume you are were measuring that current between the terminals of the motor?

After the mod on a full battery I saw 150ma.

Did you do any voltage measurements? I am only seeing .9XX volts to the motor, I forgot to check before the mod though.

I guess this makes sense though that voltage would drop as resistance was decreased according to Ohm's law...

I did the mod but removed both resistors as well. I'm impressed with ozmotear's soldering the pc jumpers. My first resistor just slid of and the second stuck to the tip of the soldering iron and I just assumed it was cooked. I think my zip is faster but I can't be sure. I'm planning to back off zips for a while untill I find a nice grey 911 and start anew with that one...my rx7 is turning into frankenstein's monster.

I dont understand how soldering a few short wires on a circuit board can increase battery capacity. can you explain this?

it's not increasing battery capacity. it's increasing the current from the battery through the board and to the motor. the circuit board restricts the flow of current and he's making it so it's not so restricted..... IE "resistors"

oops my bad

i soldier the two and i see no differanc e ..i thought i did but the 3.8 dont work and my friend brought over his and no differance..could i have messed up..and what kinda changes do you get ..also ..1 chip fell right off will that affect anything -thanks-

I'm abvously not an expert. But I would think that if the ZZ still works then losing a chip didn't hurt anything.
And despite my anti mod additude I did the same thing. I lost achip as well. I didn't notice a differece in speed, I did notice a definate delay in the steering response.

which resistor?
 

hey there, long time lurker first time caller (well, lurker for the past week or two)

so im intrigued here. if one resistor is forward, one is reverse which is which? i dont really need the increased speed in reverse (and probably shouldnt have it). and by only bridging one resistor, mightnt you get some of that lost runtime back? (probably not enough to count, since itll be relative to the amount you drive backward)

Hum.

WIll be intersting to see if the power transistor will hold. Usualy resistor are put in line to protect the transistor from blowing. Simular to R15 in the charge circuit.

Could cut the value by paralling the same value across what is there now. Would give some protection to the switch transistor.

As soon as I can get two client project done, I am planing on ripping up both a controller and car to generate voltage points and the circuit for the receiver.

based on my knowledge of computer, isnt this basically like over clocking a amd cpu using a pencil? ive done it with my amd cpu and its bridged gaps before, would this work?

Probably not.

Graphite isn't a great conductor. It'll conduct but not very well.
With the AMD chips the idea is to just get a trickle of eletricity going through those bridges to disable the multiplier lock.

With this mod to the PCB the idea is to reduce the amount of resistance in the circuit. So you would want to shortcut around the resistors with a GOOD conductor. Good wire and solder job or something.

Graphite may get electricity going around the resistors. But it might not. Electricity is gonna take the easiest path and that may be the path through the conductor instead of the through the poor conducting graphite.

Hum.

Got this very strange idea. What if this is basically a booster style car with two speeds? And it sets for 1/2 speed? The TX-2/RX-2 chips set are basicaly 5 channel RC chip set.

Well I got a few minutes so will pop a controller and ground the magic 6 pin and see what occures.

Trainwreck! :( Well it was worth a try.

All grounding pin 6 on TX-2 IC1 is stop the car.

I would recomend to find the value and cut it by 2/3 or 1/2 the value. If this is like most H configuration then those resistor are feeding like a flip flop. You could burn out the two top tranistors of the H.

This is IT!!!!!!!!
 

This was what I was looking for!!!!!!!!

I like my ZipZap better than my bit but the bit could spin the wheels and the zip couldn't. (Man did I try) I tested at the motor and saw a substancial diffrence just didn't know which resistors.

Thanks

Re: This is IT!!!!!!!!
 

So did you get this mod to work?? I'm not exactly following you here. Since alot of other people seem to be dead in the water with this, if you did get it to work, I think I speak for everyone when I say POST HOW YOU DID IT!!! :D