You'll be fine.
I thought you had a lipo now anyway.
If I make it on Sat I'll try and bring a spare.

Hi,
I do have lipos now I just haven't had any time to build a mini to take them.

Will see how I get on with Nicads this weekend.

Duane.

Which Lipo's you got? They will fit in any std mini.....

But you should be ok with Nicd's anyway...

Ive been racing with NIcds before with the mayhem and it has never given me a problem racing with cars on lipos.. more competitive than Nimh if you ask me.

Downside is it loses power slowly and I usually realize it when Im in the middle of a 5Min race

Hi,
My Lipos fit the mini, they are 3200's I think.

I thought that a fully charged Lipo puts out a lot more voltage than a Nicad ?

I will eventually built a mini for Lipos, when i tried them in the current mini it was hopless, too at the front light so no steering.

See you all tomorrow
Duane.

Don't you remember the quick tips you gave me at Area 2? When I was complaining about the understeer?

I don't think there will be a meet tomorrow, hasn't it been changed to Fridays?

By the way, I'm running a LiPo in my M05, just some minor adjustments to the setup, and it handles wonderfully.

Decrease the ride height in the front (compared to the rear), that makes an amazing difference.

Duane, mini's like a little weight, try and get it up to about 1350g and it should be good to go. The single best change you can make is to the tires.

Regarding the SSS, it will start tomorrow, at about 17h30. We dont have a lot of light so we need to start sharp. I cannot make Friday's so the SSS will need to take part on Sat afternoons if you want it timed and set up by me.
Assuming that the days for RC are changed to a Friday, then I am afraid that I will not be able to join, and I wont be able to assist you running the events. I understand that majority rules, that is simple enough but until that decision is made, Saturday is still on for those who can make it.

Lastly, I know a lot of people invested in the Sport Tuned motor for the Al-Ain trips, so we will need to reach a consensus on whether they stay in or not. Ultimately, we all need to be in agreement.

Hi,
I know the mini needs to be weighted for Lipos, but if they dont add much in the way of speed I wont rush to build a lipo/weighted chassis.

I thought I heard someone saying that fully charged lipos are putting out around 8 volts ?

Duane.

Yeah, they put around 8.40 volts when fully charged, well 8.40 to 8.49 volts.

Be careful with radio gear, some servos and recievers don't like Lipos.

Wow, I put a lipo in my mini and its definitley quicker.

Seems to handle ok without any extra weight but I will bring some on saturday anyway.

Duane

Abdul Basit wrote:

Yeah, they put around 8.40 volts when fully charged, well 8.40 to 8.49 volts.

Be careful with radio gear, some servos and recievers don't like Lipos.

What kind of servo and recievers are dangerous for Lipos?

Lots of RC Electonics are based on a power supply of around 6Volts, this is usually supplied by the speed controller. The speed controller takes the 7.2 volts supplied by Nicads and Nimhs and turns it into 6Volts for your receiver and servo.

The problem is that some speed controllers dont do this, they just pass the battery voltage right through to the reciever and servo. Most electronics can handle 7.2 volts inplace of 6 volts, but the 7.4 or more supplied by Lipos can be a problem.

To cut a long story short, if your using the basic tamiya electronic speed controller with Lipos some of your electronics may die an early death as the tamiya TEU101 does not have a dedicated voltage circuit for the electronics and just passes the battery voltage straight through. If the battery is a lipo this could be too much for your electronics to handle.

Duane

ive been using Lipos with my TEU101 since i first race on my Mini and luckily nothing happens.

There are some servos that are more capable of handling than others, typically digital servo's will be the first to die.....the Futaba S300x series seem to be immune to them, and the std Hi-Tec models are all cpabale of withstanding the beatings...

two of my towerpro ones will testify (posthumously) they they dont like it...

Duane wrote:

Wow, I put a lipo in my mini and its definitley quicker.

Seems to handle ok without any extra weight but I will bring some on saturday anyway.

Duane

I\ve never added weight to mine, and always run lipo. Not sure if it makes much difference. I do add wight to the touring car though, cos it was struggling for grip and the weight is off centre, but the mini it seems OK to me so never bothered.

The problem isn't the fact that Lipos go to 8.49v when fully charged, the problem is that when a cell drops below 3.0v... Then you see a lot of smoke..

So, if you're not using a regulator, you might blow up your pack one day...

Abdul Basit wrote:

The problem isn't the fact that Lipos go to 8.49v when fully charged, the problem is that when a cell drops below 3.0v... Then you see a lot of smoke..

So, if you're not using a regulator, you might blow up your pack one day...

a regulator or BEC controls the voltage going to your reciever and servo constant and regulated (prevents servo and reciever them from high current damage) it has nothing to do with the lipo pack dropping to 3.0v.

to prevent cells dropping below 3v you need a low voltage cutoff

anyhow your pack shouldnt blow if it drops below 3 volts per cell it will just become a brick

All but one of us are saying the same thing which is -

1) Too much voltage can damage your components

2) Most speed controllers provide a BEC or Battery Elimination Circuit which provides a 6 volt output for your receiver and servo. It gets its name because way back when, we all used to put 4 AA batteries in our cars to power these components, then as electronic speed controllers got better they introduced this circuit to eliminate the 4 AAs so - Battery Elimination Circuit or BEC was born.

3) Some speed controllers dont have this circuit and just pass the battery voltage directly through to the radio and servo. The Tamiya TEU101 which comes with many kits does this.

4) If a LIPO is used in a car with no BEC, there is a risk that too much voltage will reach your radio and servo and damage them.

5) Its unfortunate but true that this voltage is more likley to damage more expensive equipement which is designed and built to higher tolerances so while we all get away with using low end Futaba/Hitec servos, change to a high end model from the same manufacturer and its much more likely to get killed by unregulated LIPO voltage.

6) What this 'unregulated' business ? well a good BEC also acts as a regulator this is a circuit which trys to keep a constant voltage and current available to your radio and servo regardless of the damands of the motor.

7) This is the good news bit - You can buy a separate regulator so you can keep your existing electronics and know that you shouldn't damage them. A seperate regulator might even provide smoother power to your electronics and reduce any glitching you might have.

last but not least no radio gear or servo was ever harmed by too little voltage.

Lipo and Nimh batteries regularly die from too little voltage - to prevent this you can buy a LIPO cut off, or a lipo buzzer or solve all your problems and buy a speed controller with a lipo cut off and a BEC built in.

Its all been said before and its right apart from the one previous post which isnt.

Duane.