Brushless Baja with 2 Castle 1717s?

[KaztheMinotaur]

What is the continuous wattage on the 1717?

[Arct1k]

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.

[KaztheMinotaur]

Kershaw Designs conversion can accomodate 2 1717s.

Can the 1717 run 7S?

[Arct1k]

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

Originally Posted by KaztheMinotaur

Has anybody used the Leopard Ground 150A ESC?

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.

[lincpimp]

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.

[thzero]

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

[KaztheMinotaur]

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

[Arct1k]

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 :)

[lincpimp]

Originally Posted by Arct1k

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.

[Arct1k]

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

This will be perfect for most folks.

[KaztheMinotaur]

8S with a 15T pinion?

Direct drive pinion to spur?

[Arct1k]

Originally Posted by KaztheMinotaur

8S with a 15T pinion?

Direct drive pinion to spur?

Yes with the Castle 2028 and a stock 57T Spur