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jolyon
08-10-2009, 11:28 AM
Hi guys,

My son James (aged 8) and I (Jo - aged - too old boo hoo) have just sold up all our Mardave 1/12th scale stuff and decided to get into buggy racing at Stotfold because it looks a whole lot more fun and its what I used to do when I was a kid (Turbo Optima Mid era).

I am a little bewildered by the amount of choice there seems to be out there now, and I am only able to pick up snip bits of information, so some friendly advice on the whole picture would be really really appreciated.

In the way of kit, we currently have:

1. Cat SX LiPo
2. 2 x GM LiPo 2 / 5000
3. 2 sets of spektrum radio gear
4. A tamiya desert gator and a tamiya sand viper (same car, different shells) with standard tamiya 540 motors in (27T?). Bog standard Tamiya ESCs with 27T limit.
5. 2 sets of 3000mAH 7.2 NiMH for the Tamiyas which seem to deplete very quickly.
6. 2 x Ansmann xBase Deluxe chargers.

Firstly, for my son, he will racing 2WD probably with either of the Tamiyas:

1. Is there a class for this?
2. Is there any chance of being competitive with current set up or should I be looking at a lower turn brushed motor and if so which ESC?
3. Would I just be better to get him a Kyosho Lazer RTR or something like that and run 4WD? Or will that in turn need further upgrades to be competitive.

For me to complete the Cat:

1. I understand LiPos need a balancing board to charge the cells evenly. What would a suitable board be and are they expensive? I think these Lipos have two cells per pack. When I look up recommended GM part numbers on google things seem to > 100 and I thought these things were about 20.
2. I believe our existing chargers will charge LiPos so hopefully nothing to buy there. They can charge up to 5A.
3. I have no motor/ESC combo yet for the Cat. I might as well go brushless I figure because brushed seems fairly hard to get hold of economically. If so, what is a common ESC + Motor configuration (I have heard 6.5T on the grapevine). I have a 34-year old's reactions so I don't want something undrivabley quick! Also I believe the ESC needs to cut the power draw from the Lipos when they reach a certain level of discharge.
4. I have heard that reverse is not allowed under BRCA rules. Is it OK to buy an ESC with reverse and disable it for the race? I would want reverse when playing with the cars in the park you see.

Miscellaneous questions:

1. We have lost our BRCA cards but I can get hold of our numbers. Is this sufficient or must a card be produced to race?

Sorry about all the questions but like I say I am getting a bit bewildered and I am getting all sorts of conflicting advice. I would really appreciate your feedback.

Thanks a lot,

Jo

Dunc
08-10-2009, 06:16 PM
I've added some comments in red to your original post.

If you pop down the track then you should find plenty of knowledgeable and helpful members at your disposal. :)

Hi guys,

My son James (aged 8) and I (Jo - aged - too old boo hoo) have just sold up all our Mardave 1/12th scale stuff and decided to get into buggy racing at Stotfold because it looks a whole lot more fun and its what I used to do when I was a kid (Turbo Optima Mid era).

I am a little bewildered by the amount of choice there seems to be out there now, and I am only able to pick up snip bits of information, so some friendly advice on the whole picture would be really really appreciated.

In the way of kit, we currently have:

1. Cat SX LiPo
2. 2 x GM LiPo 2 / 5000
3. 2 sets of spektrum radio gear
4. A tamiya desert gator and a tamiya sand viper (same car, different shells) with standard tamiya 540 motors in (27T?). Bog standard Tamiya ESCs with 27T limit.
5. 2 sets of 3000mAH 7.2 NiMH for the Tamiyas which seem to deplete very quickly.
6. 2 x Ansmann xBase Deluxe chargers.

Firstly, for my son, he will racing 2WD probably with either of the Tamiyas:

1. Is there a class for this? Yes
2. Is there any chance of being competitive with current set up or should I be looking at a lower turn brushed motor and if so which ESC? I'm afraid those Tamiya buggies won't be competitive full-stop
3. Would I just be better to get him a Kyosho Lazer RTR or something like that and run 4WD? Or will that in turn need further upgrades to be competitive. It's not a bad car, but not many people run Kyosho so advice may be difficult to come by

For me to complete the Cat:

1. I understand LiPos need a balancing board to charge the cells evenly. What would a suitable board be and are they expensive? I think these Lipos have two cells per pack. When I look up recommended GM part numbers on google things seem to > 100 and I thought these things were about 20. TrakPower make a balancer that you can plug in series between your charger and battery being charged
2. I believe our existing chargers will charge LiPos so hopefully nothing to buy there. They can charge up to 5A. They should do the job
3. I have no motor/ESC combo yet for the Cat. I might as well go brushless I figure because brushed seems fairly hard to get hold of economically. If so, what is a common ESC + Motor configuration (I have heard 6.5T on the grapevine). I have a 34-year old's reactions so I don't want something undrivabley quick! Also I believe the ESC needs to cut the power draw from the Lipos when they reach a certain level of discharge. If you're on a budget the Losi Xcelorin systems seem good for the money - I would go no lower than a 6.5 motor to start with (something a bit milder would probably be best). Oh, and a sensored system would be preferable to sensorless (better throttle control)
4. I have heard that reverse is not allowed under BRCA rules. Is it OK to buy an ESC with reverse and disable it for the race? I would want reverse when playing with the cars in the park you see. I think that would be okay, but I'm not certain

Miscellaneous questions:

1. We have lost our BRCA cards but I can get hold of our numbers. Is this sufficient or must a card be produced to race? I believe so, but a replacement card would be a good idea

Sorry about all the questions but like I say I am getting a bit bewildered and I am getting all sorts of conflicting advice. I would really appreciate your feedback.

Thanks a lot,

Jo

Kit Jones
08-10-2009, 06:27 PM
Hi Jo,

I'll try to answer all your questions.
Yes there is a class for 2wd to seperate them from the 4wds but often in the dry they arent much slower. The Tamiya and standard motor will be slower than a car designed for racing but will be stronger so I guess that depends how good your son is. If he can lap without crashing for 5 minutes then it would probably be best to upgrade if money allows. If the motor included is a standard silver can then it will be very slow as the track is fairly large so it would be worth upgrading to a proper 27turn stock motor at the very least. If you decide to buy another car then most ready to run cars will allow you to race to a reasonable level but will require upgrading to be competitive with the fastest cars although this will be mostly dependant on driver skill. The fastest 2wd cars will be running approx. 6.5 turn brushless motors.

A quick search on the internet says your chargers will be fine with Lipos but I would check the instruction just to be sure as any problems could be very costly. Balancing boards are strongly advised although you can charge Lipos without them. I use a Trakpower v-balancer which was around 30. You may need to buy a seperate connector for it depending on the connector on your battery but that shouldn't be expensive.

Most modern brushless ESCs will have a Lipo cut off and there are lots of different versions available such as LRP, Novak, Losi, Tekin, Nosram and Speed Passion. I don't know which speed controls have reverse so you would have to go and ask at your local shop. It is fine to deactivate the reverse for racing.

The fastest 4wds will be running around 5.5 turn motors but 6.5 will be equally good and a bit easier to drive.

As long as you have a BRCA number then you will be fine to race.

Al3xis007
08-10-2009, 06:30 PM
hi im a regular stotfold member, i have a brand new 6.5 turn lrp x12 for sale 70. rrp 96
we're all friendly so if u have any probs being a noob just ask.
good to see more ppl starting up,
cu sunday alex

Al3xis007
08-10-2009, 06:33 PM
Hi Jo,

The fastest 4wds will be running around 5.5 turn motors but 6.5 will be equally good and a bit easier to drive.

i thought my 4.5 was a bit quick..... best put the 5.5 back in lol

Kit Jones
08-10-2009, 07:04 PM
i thought my 4.5 was a bit quick..... best put the 5.5 back in lol

Ive got a 4.5 in mine too but only because I broke my 5.5!

Al3xis007
08-10-2009, 07:15 PM
Ive got a 4.5 in mine too but only because I broke my 5.5!

i know dude, its my old one and its mission is to snap those fragile belts til u get fed up and buy another car !!!
im not sure its as fast as my new one, wanna give it a go? :woot:

jolyon
08-10-2009, 10:13 PM
Thanks everybody for the advice. I really really appreciate it.

For the Tamiyas:

Yes I was afraid they wouldn't be competitive but I'd like to see him go round the track with it before forking out for something quicker. Will it have the power to get over the jumps? In my day, everyone replaced the standard Tamiya motor with a 27T Demon motor, what is the equivalent now?

For the Cat:

I decided to buy a Losi ESC + 6.5T motor combo (http://www.modelsport.co.uk/?CallFunction=ShowSpecification&ItemID=30214). I'm not actually sure if this ESC has reverse but by this point my head was spinning and I forgot to make that check.

Thanks for the advice on which balance board I need to get hold of. I googled for quite a while but I couldn't find the right one.

I was surprised to find only one set of LiPo locators with the "no expense spared" Cat so I've ordered some more of these. Also the nuts on the shocks are silver and they are all anodized purple in the pictures I've seen. I bought the Phil Booth, I sent Schumacher an email queryig it but I think they'll think I'm just being picky. As long as I haven't got a "Friday afternoon" car I don't mind.

For the BRCA membership cards:

Hopefully they can find mine, with a name like Jolyon its ver difficult to get it right. I think my card is down as Jaylan or something! LOL

Thanks again for the help!

Jo

Piman
09-10-2009, 12:10 PM
The Losi ESC & Motor is a good combination. It does have reverse which can be switched off or on in the software, so no prolems there.

Look forward to seeing you on Sunday.

PS. what tyres do you have? Recomended are Schumacher Mini Spikes. Yellow for dry, Green for wet.

Weather looks touch and go for Sunday so it may well be damp.

James

jolyon
09-10-2009, 12:29 PM
Won't be making Sunday I'm afraid. My folks are down, the shell isn't painted and no gear is installed yet. Still waiting on trakpower v-balancer which seem to be out of stock everywhere.

Hopefully me, Mike and James will all start together (I don't know their handles on here).

Schumacher didn't reply about my silver nut vs. anodized purple nut query. I guess they figure I'm a "nut"! :bored:

Cheers,

Jo

jolyon
10-10-2009, 01:20 AM
I must have done something wrong with the CAT. I have fitted the GM Lipos, and the motor and there just doesn't seem to be enough room between the spur gear and the pinion.

The lipo is right up against the front bulk-head and it fits in-between the battery post and the bulk head.

Sorry, I guess this should be in a CAT specific forum. Anyway, if anyone could point out whatever headsmacker I have done wrong here I would really appreciate it.

Here is a pic:

http://www.agmtelematics.com/dl/photo.jpg
Thanks

Jo

discostu
10-10-2009, 08:16 AM
I must have done something wrong with the CAT. I have fitted the GM Lipos, and the motor and there just doesn't seem to be enough room between the spur gear and the pinion.

The lipo is right up against the front bulk-head and it fits in-between the battery post and the bulk head.

Sorry, I guess this should be in a CAT specific forum. Anyway, if anyone could point out whatever headsmacker I have done wrong here I would really appreciate it.

Here is a pic:

http://www.agmtelematics.com/dl/photo.jpg
Thanks

Jo
it looks like you have the cells to close to the centre of the car they normal fit about flush with the outer edge of the chassis.:thumbsup:

jolyon
10-10-2009, 08:42 PM
Yeah that was the problem. I moved them outwards so that they are no longer restricted by the purple motor mount which gives it an extra few millimetres which I hope should be enough

I spent all night on it on this by the way, I should have left it because I then started to make mistakes:

I managed to trash the sp1. eed controller by supergluing the supercap to the edge and fitting it to the car. I then discovered that all the LEDs were under where I had superglued the cap. So I swapped the sides, trashing the circuit board cover into thousands of tiny bits in the process :( At least now I can see the LEDs albeit through a haze of superglue. I think it will be new speed controller time on the first impact. There seems to be so much to squeeze into these cars.

The biggest problem now seems to be connecting to the LiPos without fouling the drive belt. Negative is no problem and can be securely guided through the centre of the belt. Positive is just (by 1 mm) to the LiPo side of the car and beneath the top deck. I have no clue how I am going to connect this. I'll up some photos of it as it currently ASAP.

Thanks for the advice!

Jo

discostu
10-10-2009, 09:05 PM
hey jo they have realesed a top deck with a hole in to get that connector in personely i use saddle packs in my cat as it makes it much easier.:thumbsup:

jolyon
10-10-2009, 09:07 PM
Thanks for the tip mate.