Motor and battery question

[barry]

Hi All,

I've just bought a second hand RB5 and this is my first season racing since the late 80s when I had a Kyosho Raider - happy days! I always dreamt of owning the Ultima and now I finally do.

A lot has changed over the years, so it's been a lot of work learning about the new developments such as brushless/LIPO/2.4Ghz, but I'm nearly there! I still need a battery, motor and esc so would appreciate advice from RB5 owners. I'll be racing on grass mainly.

• Motor/esc - would prefer brushless. I'd like something that will be competitive, but not hugely expensive - £100-£150 perhaps.
• battery - I'm a bit put off LIPO by the safety concerns
  • if discharging too much is a problem, won't there be a problem if they're unused over winter?
  • Can they be safely stored outside all year round, i.e. will they be ok in cold winters and hot summers?
  • if I were to go LIPO, any recommendations

NIMH - again, what would go well with a brushless system in the RB5?

Cheers for any help you can offer.

Barry

[JCJC]

Hi Barry, keep your eye on the for sale section here, lots changing equipment before the summer, Losi brushless is well thought of by some, in your price range, spect you will need something like a 6.5 or 7.5 for the RB5, we ran 6.5 in a B4 last year, was good.

You are misinformed with regard to brushless, no major problems, most modern esc's have a cutoff to stop overdischarging, and to me they seem easy to handle and charge, just charge and go, no peaking, no balancing and will last as well as nimh over winter, you may find somewhere inside to race - we do.
Remember batteries need to be of "approved make" for BRCA events (possibly not club events) and if you put lipo in you will need to add weight somewhere, they are half the weight of nimh cells.

[RogerM]

One thing to consider is the RB5 really does not like to be down on weight in it's battery tray. My findings and that of several others is that if you run LiPo you need to weight the car back to NiMh weight to get it to go. Maybe that will change in time as more people do set-up work with them!

If your starting from scratch I'd say make sure you go for a charger that can do LiPo/LiFe/A123 cells so your a bit future proof but then go and buy some proper cells, just my opinion though.

[Fabs]

Regarding the storage issue,

Lipos will not self-discharge anywhere near as much as NiMH. The actual breed of NiMH DO NOT like being kept at any point in time under 0.9V/cel, and will usually totally self discharge within a couple of weeks, meaning that you'll need to put some charge in them every so often if you're not racing, otherwise you'l be left with cells that are useless.

Lipo do not suffer from this problem anywhere near as much as their self discharge rate is very very low. Of course it is better to keep an eye on them, but once a month will be well enough.

They do not like low temperatures however so make sure you keep them out of frost's way.

[niggs98]

Originally Posted by RogerM

One thing to consider is the RB5 really does not like to be down on weight in it's battery tray. My findings and that of several others is that if you run LiPo you need to weight the car back to NiMh weight to get it to go. Maybe that will change in time as more people do set-up work with them!

If your starting from scratch I'd say make sure you go for a charger that can do LiPo/LiFe/A123 cells so your a bit future proof but then go and buy some proper cells, just my opinion though.

all of my setups use a 4900 lipo with minimal weight added. it has allowed me to make the car very supple across the bumps whilst still landing even the mega jump at worksop silky smooth everytime.

as already said have a look in the second hand section on here as there are the losi systems that seem very good value for money and also the second hand lrp/ nosrams are very good as well and have a very good warrenty system so that you can always buy in confidence even if it is second hand. depending on how much experience you have from your previous racing will depend on the motor id recomend. if you wernt the best racer in the world then start with 10.5 (sameas an old 19turn) this will make the car a lot easier to drive so that you will break less and wont be much slower than a 7.5 or 6.5 in a straight line.

as for charger and cells. personally id go the lipo route.
1 the cells need less maintenance
2 you dont need as many cells
3 the speedos above all have a lipo cutoff so you wont take the voltage to low
4 what ever cells you leave for a long period will self discharge but the lipo will do it a lot less than a nimh will.
if you are woried about leaving a lipo for a long period then get a charge pouch ( £10 )as these will reduce the risk if the unthinkable does happen.

lipos are a lot safer than nimhs. in the 7 monhs that i have used them and also in the last 2 years that my local club has used them there have been no flame outs etc that you see on youtube etc but i have seen at least 20 nimh's packs explode either in the pits or on track so ignore a lot of the scare mongery that you will hear

having said that go to www.brca.org and look up the electric board so you can find the list of brca legal lipos and nimhs and also safe charging advise etc etc

as for charger the bc6 seems to be a popular choice and it has a built in balancer or if you are on a tighter budget look at the flightpower/trackpower unit(both the same. one black one gold). small compact and easy to use as well as being cheap although bare in mind that you will need to purchase a balancer as well unless you have a race friend who also has one.

mark christopher will be able to give lots of advise as to how to treat your lipo for maximum life so look for him on oople as he is a very helpfull chap.

As for rb5 setups look in the setup section on here or feel free to pm me any questions you may have, as a beginer dont forget to stock up on spares. all cars have a weak point or 2 and the rb5 is no exception. personally to date have broken

front c hub
rear T-piece

but as a precaution i also carry wishbones, shock towers, all hubs and the above bits

[barry]

Thanks everyone - much appreciated.

Barry

[barry]

Thanks again for your help - have just bought a BRCA legal Demon Lipo battery and a Losi Xcelorin Brushless Systems from the for sale forum. That saved me a bob or 2!

Cheers,
Barry

[ramdrive]

To right Barry, I have kited my ZX-5 out with (New) Xcelorin 6.5T Combo, Lipo & Charger and (Used) Super Exzes transmitter, Spektrum 2.4 module and receiver all for under £200 notes.

The sales section has been a godsend

I also used to race in the 80's, Hotshot's & Cat's, now looking to get back into the sport.

Originally Posted by barry

Thanks again for your help - have just bought a BRCA legal Demon Lipo battery and a Losi Xcelorin Brushless Systems from the for sale forum. That saved me a bob or 2!

Cheers,
Barry

[Fabs]

Originally Posted by niggs98

all of my setups use a 4900 lipo with minimal weight added. it has allowed me to make the car very supple across the bumps whilst still landing even the mega jump at worksop silky smooth everytime.

We don't all have your driving skills mate... I cannot drive the car round with a (heavy) Lipo and no extra weight, not indoors anyway. Outdoors that might be a different matter...

[DanW]

I ran the RB5 with Lipo for the first time on sunday, outdoors at southport.

Car went really well, setup changed a little bit, suspension a little softer all round so it soaks up the bumps really well -better than it did with nimhs.

With no battery ballast added (does have lead in front end but that was there with nimh) the car was just 9g underweight but was really struggling for rear traction on the grass and cobbles. So its now weighted up quite a bit, but the overall weight is still much less than Nimh.