Techpriest

Was planning to get the TXT-1, but have started to look at the Twin-Force a bit closer. It is lighter then the TXT-1, costs $130 less, more ground clearance and includes bearings to boot. My one big gripe is the dual batteries. Anyone with a TF care to help me out? How hard would it be to convert one to twin 540 motors so I can run 7.2v? I figure I could make a motor plate with the right spacing for the smaller motors. Not having seen one up close I am afraid I might be missing something. Thanks in advance!

I know it will be slower, but should not be any slower then a TXT-1 right? I could easily make a single batt mount centered on the chassis so that is not a concern. I had an E-Maxx and really disliked the dual batts.

Crazy_Coconuts

I dont have a TF, but I'm pretty savvy when it comes to electric MT's.

Basically, if you want to run your TF on 540 motors, just put them in instead of the stock ones. Since you need to get an ESC seperately anyway, just dont get the EVX. It has a very high motor limit and isnt suitable for mild 540's.

I would say that a TF would be faster than a TXT even with the same motors because of the gearing. Just dont try to out pull one .

xism

"Just dont try to out pull one" why not? =)
just wondering

Techpriest

The 550s are all about torque. Not sure if I could find 540s with as much pulling power as the 550s.

I had another idea. I will leave the 550s in and use a 7.2 dual motor esc and a single batt. I am thinking the truck will run like a 14.4 at half throttle. Plenty fast enough for my small yard, chasing the cat in my house, playing around town. I could then just swap the ESC for a 14.4 and use 2 packs for when I want full speed. Will let you guys know how well it works.

Anyone been to Kyosho's new website? They have two Twin Forces listed now and both come with ESCs. Not sure if I want to order a TF now or wait for the ESC equipped kits that I assume are coming soon.

Techpriest

Did some more research. Both ESCs that I have been looking at are fine running both one or two packs. I can run one pack, then run two and never have to swap anything. That is great news! My T-Maxx has a few more days on eBay and then I will be ready to order my Twin Force!

Crazy_Coconuts

TXT's have a lower gear ratio. They have more pulling power.

out of curiosity which two have you been looking at? See, there are a few ESCs that can run with up to 16 cells, but its all about wiring. If you are ok with wiring up a harness that will let you run two batteries on one jack, then I'd go for it... or you might need to short out one of the battery connectors with an EVX type of ESC that has two batt connectors...

Techpriest

Mtroniks Sonik4 Super E-Truck
Waterproof, can handle from 5 to 12 cells, has hook ups for brake lights. 24 month warranty

Novak Super Duty XR
Water-resistant, can handle from 6 to 14 cells, has port for fan. 120 day warranty

I am leaning towards the Mtroniks.

Comparing the EVX to the two above it comes up lacking. From what I can find I don't see where it can handle less then 12 cells. I have heard a lot of people complain about the EVX letting the smoke out when near any kind of moisture. I am definately going to play in the snowand would like to play in mud if I think I can get it all sealed well enough. In all fairness the two above are about $40 more.

Yes, I have no problem soldering up a harness. I am a computer tech with a bunch of electronics training behind me. This is the big reason I am selling the T-Maxx and getting the Twin Force. For me, messing with an electrical glitch for an hour is a fun challange while tuning a nitro motor for 10 minutes is just frustration. I think I will buy another nitro monster when they come with O2 sensors, fuel injection and a computer brain like my real car.

Thanks!

tndiverdown

Do you realize how slow and underpowered a 10+ pound monster truck will be on 7.2V and 540s? Your runtime will be almost nothing too. IMO, your wasting your time unless you run two packs and the 550s. The only time I would run what you are thinking about is on a crawler with a really low gear reduction unit.

Techpriest

10+ pound monster trucks have been running, and racing, on 7.2v and 540s for 20 years and often have better runtime then the dual battery 14.4 trucks when given the same number of batteries. My question is not can it be done, because I know it can, my question is can the TF do it?

I have given up on the 540 motors for now anyway and plan to try the 550s first. I will set it up for use with 1 or 2 batts and see how it does. I may try 540s just to see how it compares if it does not look to difficult to do.

Crazy_Coconuts

BL Force: He changed his mind. He said he's going to run 550's on 14.4v outdoors, but only 7.2 indoors and around his small back yard.

Techpriest: Oh man! My bad, i thought you were a kid for some reason. Those ESCs are really sweet... I dont have either one personally, but I would like one. Neither are without quirks though. The Super E-Truck is a nice ESC, but unlike many of the other high end ESCs, the Super E-Truck loses steering as the battery dumps. The XR on the other hand, isn't waterproof like the E-Truck (I dont even think its that resistant to water), but you can just waterproof it by putting it in a balloon or a sandwich bag and zip-tying it closed... If you want the E-Truck, I suggest you use a seperate battery pack for your reciever (like on nitros) because the loss of steering can get annoying when you are trying to finish off the battery...

Crazy_Coconuts

bah... you replied before I did. [:'(]

when you run trucks in 14.4v's with 12 cells, the run time will be less than a 7.2 because the RPM's are higher. They have a higher amp draw at higher RPM's and they will kill the batteries faster, much like why a low turn motor kills a battery faster than a high torque one.

The answer to whether it can or cannot is simply that it is possible... It can be done. It has been done before. It has been done by racing clods, TXT-1's, etc... although they have lower gearing, the motors they use were much hotter....

tndiverdown

Coconut, I disagree. It's about power and that's why 14.4V trucks are superior to any 7.2V system. Amps X Volts = Watts (Watt's Law). Less voltage requires more current to do the same amount of work in Watts. A 7.2V system actually needs more battery current than a 14.4V system to move the truck at a given speed. I guarantee you can't get 15 minutes of run time out of a dual 540 truck with a single 7.2V pack. I average that with my stock E-maxx and 3000mah packs. You would need two 7.2V packs in packs parallel, which essentially doubles the mah ratings of the individual packs to even get near that. It still wouldn't be as fast or efficient, so what's the point in running 7.2v? Also, the 540's won't last nearly as long as 550's. It makes more sense to just step up to 14.4v. Gone are the days of the 7.2V racing clods IMHO.

Techpriest

I think I see some of the problems all around. While I am not a kid (31) my nephew is (9). I am not only getting a TF for me, but one for him as well. I did not see any reason to clutter the forum with my family situation and what all I plan to do with the trucks since I thought I asked a pretty straight-forward question, but I see now leaving it out has caused even more clutter. Without even asking who would be driving the thing some people started telling me if it did not do 30mph then why bother? I want to thank Crazy_Coconuts for not only giving me an answer, but the logic behind it. It was very helpful.

My nephew has grown tired of his Stampede (No knock on the Stampede, he has been driving it for 2 years and just wants something bigger and 4wd.) He is selling his go-kart and will have about $300 to spend on a monster. I should have about $450 to spend on mine. I was hoping we could each get the same truck mostly for the logistics.

I looked at Clods and while it would be fun for him (I had a blast with one when I was older then him), I am afraid it would cost to much to make fun for me now (need a new chassis at a minimum). I looked at TXT-1s but it is over his budget and is pushing mine. I had an E-Maxx and liked it but prefer more realism since we are both fans of real MTs, and it has the same 14.4v issues as the TF. As for speed the stock TF is too fast for him in most cases, for me in some cases, and for his friends in all case. The TF with ESC and servo will run me about $420 buying all things new, this is under my budget. I think we will sell the Stampede and that will get him close enough that I can pick up the rest. We have radios and recievers so that's not a factor.

I want to let one of his friends be able drive my monster on occasion since it is always more fun to bash with a friend. I would rather the kid not trash my truck totally so keeping them both at 7.2v will result in less parts broken and longer overall run-times.

In winter I want to set up a monster truck track in my heated garage. I figured I could get some cheap plastic toy cars for us to run over and maybe a little ramp at the end, like the real monster tracks used on TV. In this case I think 7.2v would be plenty.

BL_Force, you just proved my point about 7.2v having longer run time. You can get 15 minutes out of an E-Maxx. A single battery Clod can go 10 minutes. With 2 batteries (one at a time) the Clod gets 20 minutes of run-time to your 15. I am more worried about run-time per day, then per battery. Your 14.4v could only play as long as my 7.2v if you had an unlimited supply of batteries. Give us each the same number of batteries and I will still be driving after you have packed up for the day.

My nephews RC stuff is kept at my house so when he is around we each have 5 batteries and a charger, but when he is not around I have 10 batts and 2 chargers! When I am alone and at the big dirt hill nearby I definatley will be running 14.4v and getting full speed out of the thing. This is why I was talking about being able to swap back and forth. When playing with him I can run mine at 7.2v so it's more fair and we can play longer. At that time the focus for me is not the truck, it is simply spending time with him.

As for the days of the Clod being long gone, I am really surprised this thread has not been hijacked yet by Clod fanatics. There are plenty of them out there.

infernalstone

Clods have their places, these days. But like you said, you spend 200 bucks on the clod, and then you, like most of us, would need to drop a load of cash into it before we'd be happy with it.

MonsterCowpower

True,unless some very low turn,high RPM motors with very small pinions on a large spur are used and even then it is not very practical. RPM and more demultiplication will be needed to counter the lesser torque.

I have two BL E-Maxx trucks and a Twin Force,the Twin uses dual Trinity Monster MAXX PRO motors.This thing hauls serious

Tried dual Trinity Speedgem Extreme 13 turn triple motors,top speed was good but the lack of torque evident.

Still you want the best of RPM and torque,BL is the way.One HV-Maxx eats pretty much any dual 540 setup,and one Hacker MAXX/Schultze will buldoze any 550 brushed setup. Always better with motors using high voltage in the heavy electrics,as to get up to speed fast and attain a high speed there is no substitute for WATTAGE.And on 14.4V the AMP draw is half than a comparable WATTAGE system on a mere 7.2V.

The only way to attain high speed and have good torque with brushed would be to use Trinity drag motors,and then the life span is so short its not even funny when they are pushed.

infernalstone

Here's something I was wondering, since we're discussing electronics in trucks and such.

Can an EVX run a single 550 motor? All this talk makes me want to get my Juggernaut up and running. And an EVX w/ 550's sounds like a great way to do it. But I have other trucks I'd like to run again, but they're single motor trucks, so the prospect of having to buy two seperate speed controls is kinda crappy.

Crazy_Coconuts

infernalstone: Yeah, the EVX can run a single 550, no extra wiring needed .

Just to be clear, I never said anything about two 540's and one pack out lasting two 550's and two packs. My argument was that one battery on any two motors will outlast two batteries on the same two motors. I see your point, but I stand next to my original statement. From experience, I've always seemed to get longer run times out of one pack versus two. It is definately much slower though. I'm sure the situation changes with better batteries, as you said with the 3000's, but with my 2400's that's not the case. The extra weight makes a huge difference with only a lower mAh.

I see it as sort of balancing itself out. With two batteries, you will have more power, but then you have higher RPM's which takes off run time, and you have the extra weight of the battery which doesn't exactly do much to your run times, but it will when then you start losing power. When you have one battery pack, it takes more power to get the work done, as you said, meaning there is more resistance that causes stress. Either way, the difference is only 2-3 minutes. Hardly worth bothering youself over.

On a single pack, my dual-Titan Wild Dagger can go about 13 minutes... longer if you include the dumping period. With two packs it starts to dump at about 10 or 11 minutes.

Brushless are probably the best way to go, but it's too heavy on the wallet. I can think of better things to spend 300-500 bucks on. They are really nice though. I envy anyone who has one... *cough* BL Force *cough*

tndiverdown

Yeah, it will run only one 550 just fine.

Techpriest

Now that I have done it I thought some people might want to know how it turned out.

I bought the Twin Force and HV-Maxx Brushless kit, both new. The HV-Maxx instructions show you how to "short" one battery lead to get it to run on a single 7.2 pack. Instead of that I made a shorted plug that I can plug in instead of a second battery. This lets me run 7.2v or 14.4 and not even have to pull off the body to make the change. Kudos to Novak for that one!

I have 3300 NIMH packs and 2400 NICD packs. Nothing outrageous, but not junk either. I use a LRP Pulsar Competition 2 charger.

Battery life seems to be right about half of what it is with 2 batteries. I was hoping for better.

The HV-Maxx brushless barely gets hot after 1 pack so I can swap batteries and keep going if I want.

I thought I would need a 3rd battery mount so I can center the weight, but I really don't. I put 1 pack in one side and once you start driving you can't really tell which side it's on. It does not pull to a side or seem to be affected in a way I can notice. Seems to fall to either side fairly when hill climbing. I am sure the slower speed plays a big part in that.

For hill climbing the single battery does just as well as two. With one, the free tires spin, with two they spin faster. I want to put some heavier oil in the diffs, then maybe I can get some use out of the extra power of dual packs.

Jumping is seriously limited with 1 battery. It can get off the ground, but it does not fly. Not a lot of fun for me, safe and easy to land for a child.

Wheelies are possible if you have good traction, like grass or pavement, and a fresh battery. A few minutes into the run and they are not possible any more. With 2 packs keeping all 4 wheels on the ground is the hard part, wheelies are easy. Again, not a lot of fun for me, but easier to handle for a child.

It's about as fast as a stadium truck with a stock motor. A little too slow to be fun for me when I am in an open area.

With a single pack you can get about as crazy as you want with the steering and it keeps under control. My nephew used and entire battery buzzing all over a dirt road and grassy area today and never had to go flip it back over on it's wheels.

7.2v is the only way I will let my nephew drive it. He enjoys it and has not broken any parts. He wants one now. For a young driver I would say a 7.2v Twin Force is a great idea.

Unfortunately since I got my Twin Force the Kyosho parts have started to get scarce. I hope Kyosho gets things worked out soon so my LHS can order direct.