Brushless Baja with 2 Castle 1717s?
 

What are your initial thoughts on a brushless Baja running (2) Castle 1717s on 6s?

Go bigger and single motor.

+1
Mo Bigger Mo better

How many cells can a 1717 handle?

Well, you will have to have some small pinions and may run into issues getting the larger diameter 1717 to physically fit with those small pinions. Keep in mind the gas engine never gets much over 25k rpm, and the 1717 on 6s would be doing 35k or so. Maybe go down to 5s for 29-30k rpms? Just a thought... I would go for 6s and lower gearing, longer runtimes...

Stock pinion size is 18 IIRC, so you would need to go down to a 12t or so. Maybe throw that into BG's speed calc and see what it gives you?

As for power, I see no reason why 2 1717 motors would not move the baja just fine. A BL baja would not be twice as heavy as my lst and the 1 1717 I have in there throws it around.

2 1717, 2MMM and 2 of the zippy flightmaxx 5000mah 40c 6s lips would make a nice setup. Given the cost of 1717 motors right now you could almost buy all of the motors, escs, and lipos for the cost of a 22 series neu... 140 for the motors, 240 for the escs and 200 for the lipos. 580 total...

Keep in mind the dual vxl and similar emaxxs run just fine.

I'm trying to decide on that vs. a Leopard 5692 730KV on 12S. Probably use a Phoenix ICE 160HV w/ Pistix if I did that.

Theoretically the Leopard will produce 4882 watts and the (2) 1717s will produce a total of 5328.

The 1717 setup will weigh 1.1 pounds more.

From what I have read the leopard motors are not all that great...

Best part of the dual 1717 and MMM would be motor brakes and reverse. With a decent radio you could even setup a mix for front mech brakes and then be able to switch it off for reverse... That way you would have 4 wheel braking.

Hmm, if the 1.1 lbs is mainly motor then you will have a much more powerful system with the 2 1717 motors. OSE claims 3000watts from that leopard. I have a feeling that the 1717 would easily overpower that leopard. Why not go with 2 1520 castle motors? Easier to package than the 1717...

love to see it.
 

I would just love to see this thing opperate with two 1717's. This is what prototyping is all about, right? Give her a shot and share your results with us.

I'd say go for it! Two 1717s will beat a single Leopard motor any day. You do run into issues using two motors on a single gear though, I think I read somewhere on here that if the motors aren't within 3% they end up just fighting each other and you get a worse result.

It may be theoretically more powerful but when you figure in the added weight it will be about the same. Or am I missing something?

From what I have read the Leopard motors eem to be well like in the boat world. Where have you seen that it isn't?

Any data on the 1520? Those aren't on sale though are they?

Really wishing I hadn't sold my 2215...

Has anybody used the Leopard Ground 150A ESC?

Ah the 1520 WAS on sale, guess I just got one of the last ones. :/ So that might be out of the question for you now. Also, I wouldn't trust the specs on the Leopard Motor, my very uneducated guess is that one 1717 is almost as powerful to what that Leopard motor can actually put out. I have a 1717 and it's no joke, it could probably push a Baja around at stock gas speeds. Two would be a really nice setup IMO.

Edit: You could always consider the new Castle 5th Scale System (Mamba XL) if it's not out of your budget. I think the motor was going to be priced around $250-300? not sure on that one though...

Double Edit: If you happen to want to go the 1520 route and can get your hands on a motor I can give this new one to ya for less than I paid for it on sale.

Many people take issue with the fact that they pretty much cloned/imitated/stole (however you want to look at it) their designs from Castle/Neu. It's generally assumed that the Chinese knock-offs are lower quality, cutting corners to save money, etc. Not sure how true that is here, they might work fine. But I'd say pick up a few of the 1717 while the Castle sale is still going, support the company that actually made the design, and then you know you have a solid motor for sure.

I hear ya on that. Still just kind of thinking out loud...

What is the continuous wattage on the 1717?

Honestly I think 2 x 1717s would do fine... the motors are cheap and 2 MMM,s is about the same or less than a MMM-XL

The challenge will be getting a motor mount made...


Although I was wondering about doing dual MMM-XL and Castle 1/5th scale motors for a bit of fun... I could ask mike what it would take to create a motor mount.

Kershaw Designs conversion can accomodate 2 1717s.

Can the 1717 run 7S?

Maybe but rated for 6S... Good luck with that but I much prefer mike's setup.

Nothing special really. Just a re-badged line of old Hobbywing EZRUN ESCs. They are decent solid ESCs but nothing to really brag about. I have a couple of XERUN series (newer versions) and they seem much better and more compact.

Had a look at the kershaw setup. Looks interesting.

Anyone know what size pinion he isusing to interface with the stock baja spur? Something like an 18t mod 1.5? That seems close to stock, IIRC.

Looks like he has a few options on spur sizes for the gear reduction, 40, 45, 50, 54, 60. He is using mod 1 gears by the look of it. So given the use of the 5mm shaft on the 1717 the largest easily obtainable pinion will be a 26t. If you calculate the distance between a 40t spur and 26t pinion, centerline to centerline you get 35mm, which should be enough to clear the 50mm diameter 1717, and the layshaft.

Here is the rc calc with my best guess of an 18t mod 1.5 pinion. Factored that the ratio of 18/57 is 3.166666, and then used the spur/pinion section to calculate the gear reduction section.

Differential Ratio: 1
Transmission Ratio: 2.4000000000000003
Other Ratio: 3.16666
Spur Tooth Count: 40
Pinion Tooth Count: 26
Total Voltage: 22.20
Motor KV: 1580
Tire Diameter (inches): 5.311
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor Coil Resistance: 0
Spur/Pinion Ratio: 1.54 : 1
Total Ratio: 11.69228 : 1
Tire Circumference (inches): 16.68 inches (423.8 mm)
Rollout: 1.43:1
Total Motor Speed: 35076 RPM
Vehicle Speed: 47.4 mph (76.14 km/h)
Effective KV Value: 1580

Check my numbers and see if that makes sense... Thought the baja 5b tires were taller than 5.3... I just used the numbers in the calc's drop down menu.

If so unless much larger pinions, or more voltage is used this will not be all that fast... I would like to see alot closer to 1:1 ratio on the gear reduction, however going much smaller with the spur will cause issues getting the gears to mesh with the 1717 motor diameter. Unless we can run alot larger mod 1.5 pinion where it meshes with the factory baja spur.

6.84-6.89" for the Baja 5b tires. These are in the dropdown for the speed calc.

If you need higher pinions/different spurs,contact bryce on HBF,he owns baja skunkworks and makes gearing ratios and overdrive setups for 62cc motors.im sure he could easily modify his setup to accomodate 2 1717's--Josh

The reduction spur and pinion are 24/50 yielding a ratio of 2.083 yielding a speed of 44.08 using stock Dirtbuster tires.

A gear reduction ratio of 1.5 bumps the speed to 61.21! HA.

No reduction is 91.82 ( I can see people being knee capped now...)

Leopard motor with same reduction is 41.8.

Does anyone know what the estimated speed of a stock Baja is?

I'm also looking into a 63mm Little Screamers motor. Up to 8000 watts. Mr. Little Screamers is supposed to call me today.

A bone stock baja does 35-40, mine has been clocked at 48mph with a rear Dom and a DS engine. But I'm buying a 2-speed for christmas so I'll top out around 70 with alot more bottom end.--Josh

The Castle eBaja was 46mph on 8s with 14T pinion - I´m now running 15T and would guess I´m in low/mid 50s.

Which is fast enough for me :)

What motor are you using Chris? Stock baja pinion is 18t correct?

Seems like the Kershaw setup would help if you planned to run something like the 2200kv 1515 in pairs and needed to gear it down to realistic speeds that would not overload the motors...

Otherwise 1 big motor and a slightly smaller pinion look to be the easy choice. I still like the dual 1717 setup, if only for the fact it uses well tested components. In a year once the CC XL setup is procen and a bit cheaper it will be the bees knees.

I´m using the Castle 2028 which is 750kV - the Castle kit comes with a 14T pinion.

This will be perfect for most folks.

8S with a 15T pinion?

Direct drive pinion to spur?

Yes with the Castle 2028 and a stock 57T Spur

So what is the rpm max for the 2028? 35k?

IIRC the can said 45k... But i think that 35K would be a good operational limit.

I think patrick mentioned that 8S was its target zone and that if you went to 12s you´d need a different motor.

Just thought I'd post some pics of a Kershaw converted baja I saw in person awhile back, since that conversion was mentioned here. This one is a powered by a single 2215 personally, the other conversions out there look a helleva lot better made.
http://i91.photobucket.com/albums/k3...2/IMG_0470.jpg
http://i91.photobucket.com/albums/k3...2/IMG_0467.jpg
http://i91.photobucket.com/albums/k3...2/IMG_0468.jpg
http://i91.photobucket.com/albums/k3...2/IMG_0473.jpg

Hmm, so around 25k rpm on 8s. 12s is 35k rpm... I am guessing it will draw too much on 12s, HEHEHE. P said the 12s MMMWTFBBQ or whatever it will be called will not have any more total wattage capability than the 8s. Still sounds like a good esc to run a low kv 1521 or 1527 on 12s lipo. I am guession the 2080 should be capable of more output than the 1527.

Are they going with the same designations on the 20 series as the 15 series? So it has an 80mm long stator... Must be BIG.