Wtf.....help - RC-Monster Forums

jas21373 · **Wtf.....help -** 05.03.2011, 09:37 AM

OK .......where do I start

just fitted a 1717 CC motor to my Savage,took it out for a bash on the weekend ,Was Awesome as you would expect from a motor that big.......Well after about 10mins of going hard in the dirt ,it stopped.As I walked over to it ,the Mamba Monster burst into flames

.....W.T.F happened...
Was it under geared Maybe????

The Truck:
XL Savage
Cen diffs
Losi Centre diff 45t
40 series Mashers
1717 CC 18t pinion
6s 25c 5000mah

Mamba Monster :20% punch control,timing: normal

Can anyone put some light on the subject as I don't want it to happen again once the Monster gets back from Castle.

cheers jas

05.03.2011, 10:02 AM

I am not sure on the CEN diffs Jas. If they are the same as the Matrix then you are roughly geared for 100mph and that is way too high. Not sure if I got the figures right but have a look here. CLICK.

jas21373 · 05.03.2011, 10:45 AM

yeh ,never thought to check with that.......

So to get it down to about 50mph ,I would have to have a 50t spur and a 10t pinion......??????does this sound right.....

BrianG · 05.03.2011, 11:25 AM

Does the XL use the same transmission as the Savage X? If so, did you lock it in 2nd gear or are you using the 2 speed?

Easiest thing to do would be to enter your data in the top speed calculator, use the "export values" button, then copy/paste the information here. You could be simply overlooking something...

thzero · 05.03.2011, 12:45 PM

Quote:

Originally Posted by BrianG

Does the XL use the same transmission as the Savage X? If so, did you lock it in 2nd gear or are you using the 2 speed?

Easiest thing to do would be to enter your data in the top speed calculator, use the "export values" button, then copy/paste the information here. You could be simply overlooking something...

Sounds like he replaced the gearbox with a Losi center diff.

BrianG · 12:50 PM

Oops, I guess I missed that.

With just a 45T spur, you'll be limited on gearing, even using truggy ratio diffs. Does the Losi CD have a larger spur option? Something around 50T+?

ZippyBasher · 09:05 PM

In my heavy Maxx CD Conversion with 1717. I found the MMM does not like the 1717 geared for more than 50mph. You must have a working fan on there and may be better to run it all the time. My fan died and I didnt know and the MMM was actually smoking but still works fine... I think the caps were melting the case?....

In any case I used a Losi CD and used the 50t Truggy spur and a 14t Pinion and the motor was getting seriously close to the outdrive cup. I would go 13-14t and make sure to not get grass in the MMM.

OH BTW MY DIFFS WERE LST SO 13/43 STANDARD BUGGY. NOT SURE ON THE CENS... I think it was 55mph or so...

You can see my thread in my sig...

EDIT. This is what I mean see how close the 1717 is to the cup:

jas21373 · 05.04.2011, 05:54 AM

cheers guys,will go with the 50t spur and a 13T pinion as i have them both,I will also wire the fan so it will stay on all the time.

05.05.2011, 12:45 AM

Quote:

Originally Posted by jas21373

OK .......where do I start

just fitted a 1717 CC motor to my Savage,took it out for a bash on the weekend ,Was Awesome as you would expect from a motor that big.......Well after about 10mins of going hard in the dirt ,it stopped.As I walked over to it ,the Mamba Monster burst into flames

.....W.T.F happened...
Was it under geared Maybe????

The Truck:
XL Savage
Cen diffs
Losi Centre diff 45t
40 series Mashers
1717 CC 18t pinion
6s 25c 5000mah

Mamba Monster :20% punch control,timing: normal

Can anyone put some light on the subject as I don't want it to happen again once the Monster gets back from Castle.

cheers jas

Possible ripple effect from low spec batteries ??? You did say the esc bursted correcdt? I've seen others with the brushless emaxx thsat were running 20-25 c lipos that had the same problem and were given very stern warnings from castle afterwards about this. Castle did replace the esc's in these situations from what the posters stated. Hopefully castle will take care of you but it may come with a little ripping but hey I'l take a ripping and a new esc rather than a "sorry you ran it without properly specced batteries"

Let s all know what you find out.............

suicideneil · 07:35 PM

The battery spec was never mentioned actually, would be nice to know what the OP is running exactly?, it was also geared insanely high; always an idea to check what speed any given setup will result in and to remain realistic about what can be achieved...