Txt-1 Power Upgrade

[pilotrcuk]

Hi All,

I just got a great deal on a TXT-1 on the 'Bay, it currently has an LRP F1 Bullet Digital ESC running a standard setup (2 x 540). A lot of people seem to have opted for the 550 upgrade (Titan 550) and 14.4V. I would be interested in trying that with a 3S LiPo pack, to keep the weight down. However I'm wondering about a brushless setup such as this EZRUN setup: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...em=300309448660

At the end of the day I would like a reasonable turn of speed, relatively speaking, from the truck, but some low end torque to negotiate the odd rock or two...

Any thoughts appreciated. Oh, doing this on a budget was of interest too!!

Al

[mymonsterbeetleisbroken]

Hey,

That ezrun system isn't very quick, it would probably need the 3 cell lipo to get it moving the truck fast, as its only the 2400 kv motor. The txt-1's weight might be pushing its limits a bit.

Tried and tested options are 550 motors (from HPI's E Savage, Traxxas E maxx etc) and a 14.4 volt esc. Mtroniks and Novak make good truck esc's that'll keep cool even pushing a txt along. The newest duel motor trucks use 2 7 cell packs, so 16.8 volts is possible (the txt-1's battery tray is big enough for those too!)

I've got an mtroniks truck esc and 2 hpi 550 motors. It brings the truck up to a level that you'd expect from a big powerful monster, with a good balance of torque and top speed. I will be upgrading to a mamba monster motor in the future once I've got a bit more use out of my current set up (I've got a thing for power )

The ezrun could well be worth experimenting with, and I believe you'd be the first here to use one in a txt-1. Just fingers crossed it doesn't turn out to be an expensive way of finding out it doesn't work

[pilotrcuk]

OK, interested to hear I could be pulling more than 60A. I have an Eagle Tree data logger which I use for the aeroplanes, so I could hook that up to find out what currents are actually going through the system (well, coming out of the pack...). I went for the higher equiv. turn on the EZRUN motor shoice, thinking that was the thing to do. Do you think there's scope to go for the 13.5T (3300kV) option? That might be better on a 2S setup, 3S would prob pull too much current for sure on that 60A cont. ESC. Just seemed swapping out two 540 motors and a 6 cell NiMH pack (current stock setup) for a single BL motor and LiPo pack would be a good move on the weight front. This thing is heavy enough without 2 x 8.4V packs!!

BTW what pinions are you running on the 550s? The ESC I got with the truck should be more than up to the task if I go that route, as it's 50A / cont, 90A / 30 secs, 260A / burst.

Any tips for reducing the torque roll on the chassis?

Thanks,

Al

Hey,

That ezrun system isn't very quick, it would probably need the 3 cell lipo to get it moving the truck fast, as its only the 2400 kv motor. The txt-1's weight might be pushing its limits a bit.

Tried and tested options are 550 motors (from HPI's E Savage, Traxxas E maxx etc) and a 14.4 volt esc. Mtroniks and Novak make good truck esc's that'll keep cool even pushing a txt along. The newest duel motor trucks use 2 7 cell packs, so 16.8 volts is possible (the txt-1's battery tray is big enough for those too!)

I've got an mtroniks truck esc and 2 hpi 550 motors. It brings the truck up to a level that you'd expect from a big powerful monster, with a good balance of torque and top speed. I will be upgrading to a mamba monster motor in the future once I've got a bit more use out of my current set up (I've got a thing for power )

The ezrun could well be worth experimenting with, and I believe you'd be the first here to use one in a txt-1. Just fingers crossed it doesn't turn out to be an expensive way of finding out it doesn't work

[pilotrcuk]

Actually...has anyone done a twin brushless setup on one of these?!! 2 motors, 2 ESCs, one LiPo pack. So much for reducing weight mind you!!

[mymonsterbeetleisbroken]

I think I've gone one or two pinion sizes bigger, cant quite remember now as it's been a while since I did it.

With the torque twist, there is little you can do apart from stiffen up the shocks and make sure the sway bars are cable tied well. I did have my shocks set quite hard, but recently made them softer - the truck looks and handles better lumbering around on the suspension rather than having it set hard. When set up soft, the truck rides a little lower and has sufficient droop in the suspension to soak up a little torque twist and keep the tyres more planted.

You'll never eliminate it though, but it's what makes the txt-1 handle like a real monster truck

When it does lift that front wheel, with 550 power it can do THIS

[Lemming]

I tried a single Novak SS5800 in a Jugg (albeit with the carbon chassis and weighted wheels) - video here.

It was amazingly entertaining! Raced it against a Wild Dagger running 14.4v and it was slower top-end but pretty much even on acceleration!

Not quite got the same torque for flipping backwards as twin 550's and 14.4v but I found it much easier to control because of that.

Steve

[pilotrcuk]

Lemming, that's impressive!! Any idea what sort of current you were pulling with the SS5800? What pack were you running that with? I seem to have this all wrong, I though a lower KV setup would be more suited to a big heavy truck!! I guess it's about pinion choice too.

My truck has the kit 15T pinions on just now, though I was supplied a set of 17T pinions too. I'm wondering how small a pinion I get get for the gearbox? It's very tempting to "pull the trigger" on a higher KV EZRUN setup and see what it does, if it really isn't suitable, then I have a Vanquish it can run in.....

[pilotrcuk]

Also wanted to ask, has anyone found the single steering setup a bit soggy? Mine has a HiTec 645MG fitted, which actually seems a little slow. Also, the servo saver seems wa-a-ay to soft, considering it's a torquey servo. Is this normal? I don't have spare servo saver parts, would you guys recommend getting either a new Tamiya servo saver pack so I can tune it, or going to an after market one (suggestions?) What servos are people using on their TXT-1s?

I would like to add a second steering servo for 4WS - though because I don't have the spare parts I don't have the servo mounts/screws - I've posted in the classifieds to see if anyone can supply me the parts if they are only running 2WS - nothing as yet. If anyone can help there I would appreciate it (I'd prefer the original Tamiya parts but will make my own if necessary). My plan is to run the rear steering servo on the 3rd channel, and be able to mix it in or out, so 2WS for bashing and 4WS for crawling. Probably!!

Also, re the sway bars, they don't seem too well secured, i.e. they twist around the link under the cable tie. I don't suppose there's too much that can be done about this...

Sorry for all the questions, I appreciate your thoughts!!

[Lemming]

Lemming, that's impressive!! Any idea what sort of current you were pulling with the SS5800? What pack were you running that with? I seem to have this all wrong, I though a lower KV setup would be more suited to a big heavy truck!! I guess it's about pinion choice too.

My truck has the kit 15T pinions on just now, though I was supplied a set of 17T pinions too. I'm wondering how small a pinion I get get for the gearbox? It's very tempting to "pull the trigger" on a higher KV EZRUN setup and see what it does, if it really isn't suitable, then I have a Vanquish it can run in.....

Hiya,

It was a single 3300mah Vapextech nimh pack in there. Max current draw it can take is 35amp, so what it would be like Lipo could be interesting. Unfortunately I sold it in the end...

It ws also running stock pinion on there, so just goes to show the torque available on some of the older brushless systems.

Steve

[TWINSET]

Also wanted to ask, has anyone found the single steering setup a bit soggy? Mine has a HiTec 645MG fitted, which actually seems a little slow. Also, the servo saver seems wa-a-ay to soft

Get yourself a Kimbrough 124 servo saver or equivalent

On a normal servo, you're probably better off with the stock one, but the 645 will be better with a beefier saver.

[pilotrcuk]

Get yourself a Kimbrough 124 servo saver or equivalent

On a normal servo, you're probably better off with the stock one, but the 645 will be better with a beefier saver.

Thanks for that, modelsport were out of stock but model-junction had a similar thing in so took his only one - will need another for the rear servo.....

[pilotrcuk]

6S LiPo anyone?!! I jest, of course..... But I'm about to pull the trigger on a brushless setup...it's going to be 3S...I just don't know what yet!!

[mymonsterbeetleisbroken]

The cable tie on your sway bar is in the wrong place:

It should be where the yellow circle is.

Unless you've done that to improve articulation for rock climbing

[pilotrcuk]

The cable tie on your sway bar is in the wrong place:

It should be where the yellow circle is.

Unless you've done that to improve articulation for rock climbing

You're good!! I actually want to change all the cable ties (the others are in the correct place) to see if I can get a slightly more secure attachment (granted they need to be able to twist some).

I STILL couldn't decide what motor set to buy for the TXT (was up until 2am looking on eBay, Hobbywing, etc...) I'd like to choose the right motor straight off, clearly, but if it's not suitable then I'd like to get use out of it elsewhere. To that end, I was thinking about the 9T motor, but I don't know if that's too much for the TXT. What do you guys think? Definately going for the 60A ESC. I think!! I have a Vanquish which I'd like to make brushless...

[pilotrcuk]

Well, I got a Kimbrough equivalent (Fastrax) servo saver and fitted it to the TXT-1. I killed it on it's first run in the garden!! All I did was take a paving slab sideways at 1/2 throttle (stock setup, 7.2V) and it popped!! As you can see, the internal plastic component has sheared at the screw.

Can anyone suggest a stronger alternative?!

The stock Tamiya saver is to the left. It looks substantial enough, just it has way too much slop for my liking and therefore very poor centering.

Al

[backtomyroots]

I've always been a fan of the OFNA savers:

http://www3.towerhobbies.com/cgi-bin/wti00...=LXFNE8&P=7

I'd also recommend a metal gear servo if you don't have one.

As far as speed, I've built 3 txt-1's and slapped the first release Novak HV-Pro (MAXX) brushless in there years go in one truck. I ran that one with some success but the faster the truck is made to go the more poorly it handles (although it is fun !). I'd go with a relatively mid single brushless, I have no recommendation though. Good luck !

My txt-1's:

http://www.tcphotos.com/showroom_model.asp...ecid=670&t= (now sold)

http://www.tcphotos.com/section.asp?sid=7434&secid=669

http://www.tcphotos.com/section.asp?sid=7434&secid=947

[pilotrcuk]

I've always been a fan of the OFNA savers:

http://www3.towerhobbies.com/cgi-bin/wti00...=LXFNE8&P=7

I'd also recommend a metal gear servo if you don't have one.

As far as speed, I've built 3 txt-1's and slapped the first release Novak HV-Pro (MAXX) brushless in there years go in one truck. I ran that one with some success but the faster the truck is made to go the more poorly it handles (although it is fun !). I'd go with a relatively mid single brushless, I have no recommendation though. Good luck !

My txt-1's:

http://www.tcphotos.com/showroom_model.asp...ecid=670&t= (now sold)

http://www.tcphotos.com/section.asp?sid=7434&secid=669

http://www.tcphotos.com/section.asp?sid=7434&secid=947

Thanks for that suggestion (yes I'm running a metal geared HiTec 645MG - soon to be two). Does anyone know if these are available in the UK?

Al

[Mountain]

You're good!! I actually want to change all the cable ties (the others are in the correct place) to see if I can get a slightly more secure attachment (granted they need to be able to twist some).

I STILL couldn't decide what motor set to buy for the TXT (was up until 2am looking on eBay, Hobbywing, etc...) I'd like to choose the right motor straight off, clearly, but if it's not suitable then I'd like to get use out of it elsewhere. To that end, I was thinking about the 9T motor, but I don't know if that's too much for the TXT. What do you guys think? Definately going for the 60A ESC. I think!! I have a Vanquish which I'd like to make brushless...

I am also running a TXT-1 with twin HPI 550 and an MTroniks Super E Truck, managed to do the upgrade for £50 (new parts) Having said that managed to shear both my universal drive shafts so they have been upgraded to Revo.

Nice thing about the Super E truck is its waterproof so it really does like the mud and the torque on those motors is great.

Found that with the power the cable ties kept slipping down. The solution to this is to put a smaller tie round the cross bar at each side and loop the normal one through it so they hold it other in place on the corner. Not had one move since.