Losi Xcelorin and LRP 5300 Lipo in Cat SX
 

Just some pics of my recent build.

This is the first car I have built in 22 years, so if I made a FUBAR anywhere, please let me know.

http://www.caymanclub.net/gallery/fi...3/dsc00544.jpg

Wires to the ESC are nice and short from the motor. This orientation means the LEDs on ESC are on the outside and easy to see.

http://www.caymanclub.net/gallery/fi...3/dsc00545.jpg

The vertical outlet of the Corally works better with the LRP LiPo. It keeps the wires well away from the belts.

http://www.caymanclub.net/gallery/fi...3/dsc00546.jpg

But you have to be very careful how you place the front as the bumps on the LiPo only have approx 1.5mm per side clearance of the 2 front pulleys.

You can also see the velcro I cut to shape on the LiPo and strap. I also used the locators to make sure the LiPo didn't slide around and hit the pulleys.

When I tried the same 5300 pack in a CAT SX, I am sure that the inside hump on the casing rubbed against the pulley for the front belt. This was with the LiPo slammed against the servo as per the manual. And the servo position/spacing cannot be changed.

Has anyone had any thoughts/ideas on this?

You didn't sand and glue the carbon fibre edges:)
I suggest doing this, as carbon fibre can split after a crash.

Matt, if you push the LiPo against the back of the servo the hump DOES rub on the pulley. That is why I centred the bump between the pulleys, marked up the position, and glued the battery locators to the bottom, and then doubled it up by using the velcor to make sure it won't move. It works fine.

In retrospect, it would have been a lot easier to get Trakpower LiPos and then the position wouldn't matter. But I didn't know that when I bought the kit and battery :)

Rossi, I'm not sure if I can really be bothered doing that. Sounds like a lot of work. If it splits I'll just buy a new bit, I think.

could you space the servo a few mm out to give room for the LiPo?

You can buy short Losi sensor wires ;)

Can the cap or zip tie hit the fan in the event of a crash? If they can then you will break the fan blades, other than that it looks good.

Just get a screw driver and dab some glue on it, then run it around the chassis and towers.

I play with Ryans because he wasn't getting proper lock on the steering, they seem very sensitive to small adjustments and it took a while to get it right, it may work though.

I never bother doing any of that prep work to any carbon fibre that I run, it always holds up just fine.

its all internal stuff in the CAT SX anyway with the undertray on.

There is plenty of room for the Lipo. Too much room. If you push it up against the back of the servo the bump hits the pulley. You need a packer between the servo and Lip really. The position of the Servo is not a problem.

Southwell, I'll take a look at the cap. The battery and motor leads were MASSIVE, but for some reason the Cap leads are very short. That is why the cap is hanging over the edge.

Servo size affect battery placement too. I've got a savox servo which is very compact and it means my battery has a lot more width that the instruction suggest.

I run the lrp 5300. I cut the hump off so it clears the pulley. I cleaned up the casing and filled the hole with sealant and smoothed it off. Presto, put the battery up to the back of the servo and can still run the servo without spacers. Perfect(in my opinion). :D

If you want to fail scrutineering at a BRCA event :cry:

G

Sorry.

disregarding his mods, they allow 5300?

I'm assuming that altering casings in any way is not allowed then? Thats fair enough, otherwise its open season for cut and shuts. Are you allowed to glue stuff to the casings? The lipo locaters on Cats are glued to the lipo. Does that not compromise its structural integrity? Only a thought. I will buy a new lipo for brca events then. Need to know which ones are allowed then. Any news on that?

TBH I think 5300 is not allowed. Not sure but I think I read that its got to be 5000 or less?

max capacity is 5500 for the 09 brca lipo rules,
You should give patience and wait for the EB list of all the legal lipos for the 09 season which should be out late february sometime otherwise you'll be taking a big gamble on what cells will be legal or not as no-one knows at current.
Cutting parts off your case and filling in holes would most certainly be failed at scrutineering at a brca event. Glueing chassis locators onto a lipo should be fine, it's if you break through the case in anyway that isn't allowed.

So decent chance the high cap trakpower cells will be ok. I bought a 4900 for regs but would like to buy a 5400.

The main problem with all the current cells out at current like the trackpower cells is that they arn't factory sealed so will still be illegal! See the brca lipo rules for 09 below c&p'd from the brca web

3.3 Lithium based (LiPo) battery packs must have a hard, protective case that
completely envelopes the cell(s). The case should be made from ABS or a similar
material. The two halves of the case must be factory sealed in a way that any
attempt to open the case will destroy the case. The only opening in the case that is
allowed, is for the exit of wires.
3.4 For 7.4v Packs: The maximum case sizes allowed are as follows: -
Length: 139.0mm.
Width: 47.0mm. (The max. width includes any side exit wires).
Height: 23.5mm. (In addition, chassis location protrusions are allowed)
Saddle-Pack cells are allowed, and must comply with the above width and height
dimensions. Saddle-Pack cells must have a combined length dimension of 139.0mm
max when placed end to end.'
For 3.7v Packs: The maximum case sizes allowed are as follows :-
Length: 93.0 mm
Width: 47.0 mm
Height: 20.0 mm
3.6 The battery pack shall have leads extending from the case for the positive and
negative electrical connections using wire of adequate size to handle discharge rates
acceptable to racing applications. Alternatively, the case shall have internal
connection points for these wires clearly marked positive and negative so the user
can apply the lead wires. It is strongly advised that the link wire for Saddle Pack cells
utilises a plug which will separate with any undue force.
3.7 The case must have the original suppliers label intact, stating the rated voltage
and the pack capacity. Maximum capacity is 5,500 mah. The Brand name/logo shall
be easily readable.

But trakpower 4900 is already allowed isn't it?

No cells have been made legal for the 09 season for any brca events yet!
The official EB list of legal lipo cells for 09 isn't out till late february!
The trackpower cells arn't factory sealed aswell at current so will be illegal until they bring out new factory sealed lipos!

Nice one. Thanks for that. I'll wait till the list appears until I buy more packs then. I'll use the lrp(modded) at our club until then. If only the lrp was flat! Thanks for the input. I'd have looked a tool turning up with those packs at the regionals.

Ok but they were legal in 08. Are they really likely to rescind that?

Now I know why people are getting so worked up on the batteries threads I've been ignoring lol :lol:

Well some regions allowed them, but they wern't legal for nationals. I hope we get something soon, im down to two working packs. :cry::woot:

I would like to think that the EB will consider the heatshrink over the packs to be classed as the factory seal. If this is removed then fair enough, the seal has been broken.

If you look on any packaging, the seal is usually a bit of plastic and a sticker.

Im pretty sure is doesn't say factory glued ;)

wonder if trakpower would let people send them back to base for inspection+seal sticker.

What exactly is the reasoning behind this rule?

to ensure no-one has tampered with the lipo cells inside, it's all about the health and safety :woot:

Damn, and there I was about to tear it down and change the lithium formulation with some added kryptonite. Now i'll never win :cry:

Forgot to say thanks for the pics. Where are the LED status lights on the xcelorin as I don't want to cut cables and realise I've arranged it so I can't see them! The manual cunningly doesn't have a diagram showing where they are! In fact it doesn't even say where the button to change modes is but I'm guessing its the microswitch on the main power switch?

Hoping to do my wiring tomorrow if I get a moment.

I know!! I spent ages looking for the LEDs before I had it wired up. It was pure fluke that I had the ESC the right way around to see them! The manual is good, but missing such a basic thing like that is s bit stupid.

In the top photo the LEDs are on the bottom side of the ESC, facing the wall of the bottom tray. Really this is the only way you can orientate the ESC and be able to see the LEDs. And yes, the push button is the one on the switch. You will need to be able to see the LEDs for programming.

After my first "incident" with the Xcelorin, with this second unit I assembled the whole thing and ran it for 20+ minutes in the carpark at work to make sure everything was running fine, and only then started tidying up the wires. Did the battery harness first, then tested it again. And finally shortened the motor wires and tested again. All good this time apart from the lack of reverse with the 010128 software (010125 works fine).

The only difference you might want to make to mine would be to come 90deg out of the Corally connectors out of your Trakpower LiPo. On the LRP the terminal sockets are recessed, so not possible to come out 90deg, hence the out-top way I soldered to the Corally plugs.

Sorry guys I went to bed early last night, but I think it has all been covered.

• You are not allowed to modify the hard case.
• NOTHING is legal yet.
• Heatshrink is not classed as factory sealed - it can be removed without tools (unless you include Lee as a tool - then a tool can remove it)
• The factory seal has to mean the case is damaged if it is removed.
• This rule is to stop tools fiddling with the lipo internals.

G

Yeah I wasn't sure about 90 deg or not. Your way does a nice job of keeping one of the wires out the belt. Maybe one done each way is best. Think I'll just wire it up with long leads to start with then modify as you did.

Shame about your reverse problem, did you manage to sent the full reset to the ESC after upgrading as the data format for its settings appears to have changed so they need blanking and doing from scratch. If you didn't, it would also explain why it works ok when you downgrade as your settings would then be in the right format.

What? Say again?

How do you send a "full reset" to the ESC after upgrading?

Funny thing is, today I was massing around in my kids nursery playground and even with the 125 software, reverse wasn't working. Something strange is going on, and I'm not sure what.

Maybe I need to try another transmitter.

On the commands drop down menu, click 'reset to factory defaults' once you've upgraded.

Oh yes, of course. I followed all the instructions on the PDF and in the manual, to the letter.

Everything else works fine, just there was no reverse with 128, and now for some reason the reverse with the 125 firmware has stopped working.

sounds like a duff unit :(

Well that was famous last words. Mine won't reverse either. Leaning towards just returning the unit for a refund as was warned off losi and if their firmware is still shit I've not got time or inclination to be the guinea pig.

I know what you mean. I wish I had sprnt the bit extra on a Speed Passion system or Notvak.
and see wha
I'll have a word with Marc and see what he suggests.

Late Feb??:cry:

Where is that from, if it's late Feb it'll be longer than I thought before I can run the Cat! Assuming it's then possible to actually get anything on the list, I bet there will he quite a rush of buyers!