BT-01 Dual motor 4WD

[Frankster]

BT-01 Dual Motor 4WD

Anyone have 2 kits and can try using 2 motors and 2 gearboxes for 4 wheel drive?   A Clod Buster dual motor ESC will be required To make the elect is work.  
 

 

[alvinlwh]

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[Pylon80]

7 hours ago, Frankster said:

BT-01 Dual Motor 4WD

Anyone have 2 kits and can try using 2 motors and 2 gearboxes for 4 wheel drive?   A Clod Buster dual motor ESC will be required To make the elect is work.  
 

 

One motor will run clockwise and the other counter-clockwise. Which motor (s) did you want to use?

Edit: I don't really know the BT-01 so that might not even be the case. Interested to find out though

[DTSCB]

I'm interested. 

Is this just an idea... or did someone actually do this?

I know very little about the BT-01 platform though. 

[FuzzyFlynn]

27 minutes ago, Pylon80 said:

One motor will run clockwise and the other counter-clockwise. Which motor (s) did you want to use?

I have not checked the manual but you might be able to fix that by flipping one of the diffs.

[Frankster]

55 minutes ago, DTSCB said:

I'm interested. 

Is this just an idea... or did someone actually do this?

I know very little about the BT-01 platform though. 

Just a though looking at the diagrams. I do not have one and hope someone can confirm it is possible

[Juggular]

You could just use 1 motor (to make it 4WD).  Like @FuzzyFlynn said, the diff can be flipped. So you don't have to worry about the direction.  

I've seen a Japanese dude selling a shaft extension for MB-01.  Or maybe it was just a longer shaft.  All you had to do was to drill a hole on the cover.  The problem for MB-01 was that the shaft couldn't go anywhere because of the battery. (Unless you have a saddle pack.)  But BT-01 has the battery raised up, so that the shaft could reach the rear diff.  So something like that would make it 4x4.  (And it might come with a cover with a hole on this side already.)

EDIT: I found the video. 

I remembered wrong. He just stuck a 3D printed shaft to the gear.  I don't think that's the most secure way.  I wish Yeah Racing or Jazrider could make a longer shaft that could connect to both drive shafts.  Anyway, it could be done with 1 motor.

 

 

[alvinlwh]

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[Frankster]

4 hours ago, Juggular said:

You could just use 1 motor.  Like @FuzzyFlynn said, the diff can be flipped. So you don't have to worry about the direction.  

I've seen a Japanese dude selling a shaft extension for MB-01.  Or maybe it was just a longer shaft.  All you had to do was to drill a hole on the cover.  The problem for MB-01 was that the shaft couldn't go anywhere because of the battery. (Unless you have a saddle pack.)  But BT-01 has the battery raised up, so that the shaft could reach the rear diff.  So something like that would make it 4x4.  (And it might come with a cover with a hole on this side already.)

EDIT: I found the video. 

I remembered wrong. He just stuck a 3D printed shaft to the gear.  I don't think that's the most secure way.  I wish Yeah Racing or Jazrider could make a longer shaft that could connect to both drive shafts.  Anyway, it could be done with 1 motor.

 

 

Interesting. 
 

if the BT-01 is 4WD, overall it will be similar to a TC-01 in layout?

[Mad Ax]

I've not got a BT-01, but I've done this with an old M01/02 hybrid with twin motors.  You have a weight penalty over a regular 4wd car but the acceleration is incredible and there's something very robust about driving it.  Since there's no centre diff, it seems to do something weird to the handling - the Clod and the Wild Dagger are the same, although less noticeable because they don't handle so well out of the box.

I remember seeing a few twin-engined cars at a drag strip back in the day - an old Mini with heavily modified A-series engines front and rear, and also a Vauxhall Nova with a 2 litre red top at either end, which left the tree like a bullet from a gun, and building my Twini was more about replicating those crazy specials than it was about making a serious race car.

If you're serious about a 4wd car then buying a dedicated 4wd car will almost certainly be better, but it's this sort of crazy special that really gets my interest.  I've been meaning to do it with a TA02/FF01 for a while, but I haven't got around to it, and I haven't checked the FDRs to see if I'll have mismatched wheel speeds.

I've not seen the BT-01 manual, but I would have thought Tamiya designed it so you could run modern timed motors in both configurations - so you may not have to run one motor backwards.

[Honza]

1 hour ago, Mad Ax said:

I've not seen the BT-01 manual, but I would have thought Tamiya designed it so you could run modern timed motors in both configurations - so you may not have to run one motor backwards.

MB-01 and BT-01 have an extra differential gearcase within the bulkhead for this exact reason - to easily swap direction.

15 hours ago, Frankster said:

Just a though looking at the diagrams. I do not have one and hope someone can confirm it is possible

The whole chassis is rotated when swapping between front and rear motor position. That means, there's no space to put a second motor. Unless you somehow Frankenstein two "motor" chassis halves together.

[Dakratfink]

Twin engine 4WD ? You might have to find this body for it .

 

[DTSCB]

After looking at this picture, what you want to do comes better into focus.  I don't see why you couldn't do both.  I'm sort of tempted to buy two kits to find out!

[Frankster]

6 minutes ago, DTSCB said:

After looking at this picture, what you want to do comes better into focus.  I don't see why you couldn't do both.  I'm sort of tempted to buy two kits to find out!

A few guys clarified the between the left image and the center image the entire chassis has been rotated at 180°.  It is not as simple as just moving the motor and transmission from mid front to mid rear.

 

good news, based on the right image, it looks like the center driveshaft goes below the battery to drive the rear wheels. This means potentially you can convert this to a four-wheel-drive BT – 01.

[DTSCB]

Ok, I take it back.  I don't think this is possible.  Noticed the chassis direction is switched between the left and middle cars in the diagram above?

https://www.tamiyausa.com/shop/spare-parts/rc-mb-01-ld-parts/

It looks like a two part chassis that you couldn't take only the gear box side twice.  OR, maybe you can if you fabricate the joining?

 

 

[DTSCB]

2 minutes ago, Frankster said:

A few guys clarified the between the left image and the center image the entire chassis has been rotated at 180°.  It is not as simple as just moving the motor and transmission from mid front to mid rear.

 

good news, based on the right image, it looks like the center driveshaft goes below the battery to drive the rear wheels. This means potentially you can convert this to a four-wheel-drive BT – 01.

Does the gear box have two outputs to do this?

I've tried, but can't find the BT-01 Manual online anywhere. 

[cstorckiii]

This guy kind of shows the FR spur/motor box change on camera. It looks like it uses a longer spur shaft and a rear facing output cover, but seems to keep the the output cup in the original position as well. So maybe, just maybe, all you need is a second diff unit.

[cstorckiii]

Here’s a more detailed FR conversion…

[cobalt]

I hope this works

One thing i always wanted to to try with dual motor setup, is to have the front motor with a sligtly higher rpm just to get little more front traction.

This would be the ultimate rally chassis!

I am really liking this new chassis its a tinkerer's dream 

Something i am realising over the years:  the models that have stuck with me are the ones i could modify/tinker with!

[Juggular]

Oh, yes, that video @cstorckiii linked shows that one motor can do 4WD. 

The shaft is long enough to reach both diffs at the same time.  

The gear cover has a hole already. 

The connectors for the shafts are rotating whether you connect them to the front diff, rear diff or both.  

All you'd have to get are another diff, drive cups and dog bones.  

And the diffs can be flipped just like MB-01.  (Below is for MB-01, but it shows how the chassis have R and F written on it. Depending on how the diff is set up, it will show F for FWD or R for RWD.)  

Of course, if you like to experiment with a 2 motor setup, that's fine too.  But just as @Mad Ax mentioned, 2 motors tend to be wonky.  I do not like the driving characteristics of Wild Dagger (which has 2 motors and 2 gearboxes).  No motor can be exactly the same, so the front and the rear end up fighting for traction.  That's like 2 siblings fighting for attention-- It's only fun for 2 minutes.  

 

[cstorckiii]

Answer to another question; BT01 and MB01 use the same lower deck (51725). This is the end that the BT01 high mount battery tray mounts to. So, with both kits and clever relocating of the steering servo, a 4WD MB01 can be made entirely out of kit parts... I think.

[Juggular]

I think that could work.  Some part for BT-01 could have a shaft going through the battery compartment. 

If you have the motor and the servo in front, steering linkages would stay in front.  The battery won't block linkages. 

MB-01 has protruding parts on top.  So buying the corresponding part from BT-01 could solve the problem. It seems the position of the battery is different.  

The battery on MB-01 is right next to where the pinion would be.  BT-01's battery would be about 3 inches away from where the pinion would be. That's different, but I suppose it has to be that way for front-motor RWD.  Otherwise, the wheels with power won't have any grip.  

But of course, if one has a plan to go 4WD, it's better to go with BT-01.  

 

[Kowalski86]

1 hour ago, Juggular said:

But of course, if one has a plan to go 4WD, it's better to go with BT-01.  

I think the best (if boring) plan, would be to go with a TT-02.

[cstorckiii]

Oh sure. If you want to do it the easy way… 

[Frankster]

22 hours ago, cobalt said:

I hope this works

One thing i always wanted to to try with dual motor setup, is to have the front motor with a sligtly higher rpm just to get little more front traction.

This would be the ultimate rally chassis!

I am really liking this new chassis its a tinkerer's dream 

Something i am realising over the years:  the models that have stuck with me are the ones i could modify/tinker with!

Fully agree.  

Love the idea of tinkering / modifying Tamiya kits to give it additional individuality