Losi LST E-Conversion Kit

[_paralyzed_]

Originally Posted by Overdriven

I wasn't a fan when I first saw it either, as evidenced by my post on page two. But it is a kit you can work with. I got a really good deal on a Aftershock with the Losi kit with Losi single speed and MMM2200 combo. Driving it is like driving a cc2650kv powered rustler on 4s, yea it's that bad. But it's not hard to cut the upper deck off the battery tray (leave the upper slots for the straps) and mount it up front. Switching to a erevo rx box saves some space and a piece of plexi with a TRX MMM mount takes care of the esc out back. Truck drives like it should now, still wheelies but alot more controllable. Gearing is prettt much limited to 25/63, can't go smaller on the pinion or spur. But this works well with my current 1520 1600kv on 5s combo.

I don't know if you necessarily need the full LST2 conversion. I do know with the 1515 every run I was either spinning the 14mm hex in the rim or spinning the pin inside the hex! I had another MMM and the 1520 so the 2200 combo was sold to fund the LST2 conversion. Can't complain as I have about $75 into the roller at this point. When I eventually make it into an XXL with center diff, I'll assemble all the leftovers (basically an aftershock) and see how it holds up, with 17mm hexes and rims this time though.

Hey Overdriven- want some fun news on LST center diff conversions? Ofna Ultra series center diffs are a direct replacement for the tranny. and you know how the driveshafts just barely sit in the cups on the LST tranny? An Ultra center diff is a hair wider than an LST tranny, so the driveshafts fit in the cups even better than a stock tranny. Use an ultra dm-1 spool if you want, or a center diff. I have a spool in my LST conversion. I'll get updated photos in a day or two. You'll see them here in the brushless section.

[Overdriven]

I seem to remember reading that, I believe in your LST thread. Thanks for the heads up though, look forward to seeing more of your build. Not sure what diff to go with, I have an RC-M losi mount but no diff, and I might go bigger than XXL to 1/6 like brian015's latest build. Gotta see what I can fit in between the rails (inspired by Bondo's build) and do some gear calcs too.

[coolhandcountry]

How are the Losi holding up?
I haven't seen many talk about breakage.

[Robl45]

couple questions here, hopefully someone can answer. I converted my lst2 to brushless probably 4 years ago. used the fine design mount and an xl11 motor I think it was and a used FD battery tray that i picked up. its worked fine for me but the I got a forward only esc and have no place to really mount it, rigged it so it works the way it is but not really happy with it.

this kit looked nice because the battery box has the esc mount on it which would help.

So anyway, can someone explain why you have to change gears in the transmission? I never did and the truck has run fine for me and its on 6s as I had the batteries laying around. way too damn fast to be fun though with the current setup.

Also, if I wanted to ditch the mechanical brakes and mechanical reversing, I would need to do the forward only conversion, is that correct? I'd also have to ditch the 2 speed and just go one speed with a dude racing hub?

[Overdriven]

There's no need to change the gearing inside the transmission when going brushless. I'm guessing you've seen the Losi Conversion kit has different bevel gears and seen some people switch to XXL spec bevel gears. Both the XXL and Losi E-kit gears will make the truck faster. If you're happy with how it is there's no reason to change.

If you want to ditch the mechanical brakes you have to ditch the 2 speed and convert to single speed. With the 2 speed you cannot use esc/motor braking and have to run mechanical brakes due to the one way bearings. The Dude makes a nice single speed hub, the Losi is cheaper. You'll also need a car esc with braking.

To ditch the mechanical reversing you have to do the forward only conversion. The only one availible is from Losi. Or if you're cheap you can use some JB weld on the gears inside to hold them in forward like I did on my nephews LST. Works just fine, but the extra gears are still in there addidng weight, unfortunately just didn't have the cash for his truck.

[Robl45]

Originally Posted by Overdriven

There's no need to change the gearing inside the transmission when going brushless. I'm guessing you've seen the Losi Conversion kit has different bevel gears and seen some people switch to XXL spec bevel gears. Both the XXL and Losi E-kit gears will make the truck faster. If you're happy with how it is there's no reason to change.

If you want to ditch the mechanical brakes you have to ditch the 2 speed and convert to single speed. With the 2 speed you cannot use esc/motor braking and have to run mechanical brakes due to the one way bearings. The Dude makes a nice single speed hub, the Losi is cheaper. You'll also need a car esc with braking.

To ditch the mechanical reversing you have to do the forward only conversion. The only one availible is from Losi. Or if you're cheap you can use some JB weld on the gears inside to hold them in forward like I did on my nephews LST. Works just fine, but the extra gears are still in there addidng weight, unfortunately just didn't have the cash for his truck.

okay, so mechanical reversing I can get rid of with the forward only conversion. Then I can stick 2 speed and use the mechanical brakes or do the one speed hub. I didn't know losi has a one speed hub??

truck is plenty plenty fast right now. even with the wheely bar, I managed to flip it on its back the other day and watch it slide down the street. ate right through the back lip of my beautiful almost new body. Yea, a couple of tears were shed.

So is it better to keep the mechanical brakes? what are the pros and cons?

[Robl45]

one other question, what size motors will the lst electric conversion fit? With the mounts I have now from fine design, I can fit 36mm motor and if mine every goes, it seems 36 mm motors are in short supply so will the losi electric fit the 36 mm and other sizes?

[Overdriven]

Mechanical brakes take some load off the esc and motor resulting in lower temps on both. Mechanical brakes also allows the use of esc's that don't have brakes like air and boat esc's. Some people also like the feel of mechanical brakes too.

How are the temps of your motor? An 11xl is not the most efficient motor out there and ditching the 2 speed and mechanical brakes will make it work harder raising temps. Ditching the 2 speed will make it easier to control wheelies though.

Edit: If you read the through this thread you will see the Losi kit fits up to 42mm motors. I found the Losi mount held heat in the motor since a 42mm motor won't contact the mount along the can so it can't act as a heatsink. Read through my other post regarding layout and gearing limitations.

[Robl45]

Originally Posted by Overdriven

Mechanical brakes take some load off the esc and motor resulting in lower temps on both. Mechanical brakes also allows the use of esc's that don't have brakes like air and boat esc's. Some people also like the feel of mechanical brakes too.

How are the temps of your motor? An 11xl is not the most efficient motor out there and ditching the 2 speed and mechanical brakes will make it work harder raising temps. Ditching the 2 speed will make it easier to control wheelies though.

Edit: If you read the through this thread you will see the Losi kit fits up to 42mm motors. I found the Losi mount held heat in the motor since a 42mm motor won't contact the mount along the can so it can't act as a heatsink. Read through my other post regarding layout and gearing limitations.

I just wanted to confirm that it would also fit a motor as small as 36mm.

[Mozzy]

Originally Posted by Robl45

I just wanted to confirm that it would also fit a motor as small as 36mm.

Here are a few pics of mine.

I managed a very simple cheap conversion. Then I bought the Losi Single Speed Conversion, which needs longer bolts to hold the gear & put nuts on the exposed threaded end. I had mine fall off. With nuts, no problem!

Now running a 34T pinion. This motor is the 1717 1580kv Castle motor, Castle Mamba Monster on 6S. The closest thing to it now is the XO-1 motor.

Also, I changed to motor brakes because I could not get it to stop or stop chewing through brake pads & discs. They would glow red in the night time!!















A little video on the beach with paddles.

[Robl45]

you did the forward only conversion as well I assume? I think I'm going to ditch the mechanical brakes when I redo this. they were a pain to change the first time anyway.

But if you ditch the 2 speed, then the motor heats up a lot more because you don't have the lower gear to start it off right?

Originally Posted by Mozzy

Here are a few pics of mine.

I managed a very simple cheap conversion. Then I bought the Losi Single Speed Conversion, which needs longer bolts to hold the gear & put nuts on the exposed threaded end. I had mine fall off. With nuts, no problem!

Now running a 34T pinion. This motor is the 1717 1580kv Castle motor, Castle Mamba Monster on 6S. The closest thing to it now is the XO-1 motor.

Also, I changed to motor brakes because I could not get it to stop or stop chewing through brake pads & discs. They would glow red in the night time!!















A little video on the beach with paddles.

[Mozzy]

Well, you need to gear appropriately for your motor & wheels too.

I originally built this as a racer with a .32 engine, then converted it years later.
So, it was already sporting the FOC kit with a gear flip which increases speed. I have also changed the bevel gears to the higher ratio for more speed since being converted.

I'm using a motor much bigger than yours because I wanted the torque to be able to gear up for insane speeds. Last clocked chasing with a car at 100km/h at 3/4 throttle (still to try the 34T pinion on the freeway). My motor gets to about 65-70 degrees Celsius, not sure of Fahrenheit, after a full pack doing WOT runs. ESC has a fan & it rarely turns on. Unless it's a 30+ degree day.

If I gear down it will flip constantly, but, this is still a wheelie king!!

Another thing, I soon discovered that my truck was mostly starting off in 2nd gear anyway as the torque produced was overriding the two-speed clutches instantly!

This next video is running my original setup (See pic) which was a +4 over stock on metal gears which explains the ringing noise in the camera.


http://www.youtube.com/watch?v=gmbs_-iFO9A

[Overdriven]

A 36mm motor will bolt into the Losi mount, the mounting pattern is the same. Your 11xl motor is a older design 2 pole that now a days would be considered marginal depending on how fast you want the truck to go. They're not bad motors, things have just improved so much. The 2 speed does decrease the load on the motor at lower speeds and from a stop decreasing temps somewhat. You also have the advantage of a pretty low Kv and higher voltage improving efficiency and lowering temps also.

If it were me, I'd try it as a single speed with your motor and go from there. Try gearing it for about 40mph or with a pinion that has the same tooth count as first gear. You might have to add a heatsink/fan but that's pretty common for those motors. Some more detailed info on your current setup and future plans will help. Motor Kv, current esc and future, current gearing 1st and 2nd, tire size, etc.

[Robl45]

Originally Posted by Overdriven

A 36mm motor will bolt into the Losi mount, the mounting pattern is the same. Your 11xl motor is a older design 2 pole that now a days would be considered marginal depending on how fast you want the truck to go. They're not bad motors, things have just improved so much. The 2 speed does decrease the load on the motor at lower speeds and from a stop decreasing temps somewhat. You also have the advantage of a pretty low Kv and higher voltage improving efficiency and lowering temps also.

If it were me, I'd try it as a single speed with your motor and go from there. Try gearing it for about 40mph or with a pinion that has the same tooth count as first gear. You might have to add a heatsink/fan but that's pretty common for those motors. Some more detailed info on your current setup and future plans will help. Motor Kv, current esc and future, current gearing 1st and 2nd, tire size, etc.

the current gearing is whatever the stock LST2 comes with. The tires currently are cen chevron tires, 7.5 inch I believe. Current ESC is an airplane ESC 100amp that came from bp hobbies, they don't seem to sell it anymore, the 60amp they sell is basically the same thing. I think thats part of the problem for me as I don't think the airplane esc has the throttle response I need. It works but its nowhere near as smooth as my sons new mini summit brushless. The motor kv I believe is 1500KV or somewhere around there.

I would like to go with a hobbywing ezrun 150amp esc or the turnigy 150amp although probably the hobbywing as it seems to have a much better rep and its only like 12 bucks more.

That opens up the option of going single speed and forward only which i'd like to do as I much prefer the motor braking.

One big question is I see pretty much all the motors are 2000KV and higher and that seems what everyone is running. Can I run that type of KV on 6s? I'd prefer to be able to buy a simple 40 dollar brushless motor and replace it if needed. Don't have the bucks for the expensive stuff. When I did the conversion years back, I was told you needed lower KV , but I seem to be reading a number of places that people are using these higher KV motors on 6S.

EDIT: one other thing, are there other motor mounts for this truck besides TDR, Losi and Fine Design? Just wondering because I see a number of motors with heatsinks built into the casing and pretty sure those aren't fitting in the losi mount and definately won't fit the FD mount which leaves the TDR mount which IMHO looks like the best option, but its also quite pricey.

[Overdriven]

An airplane esc generally isn't as smooth as a car esc. The Hobbywing will be more controllable as it is programmed for car use. The reason you see more higher Kv motors out now is because the most popular conversions are buggies and truggies. Most of them are limited to 4s use in the classes they race in and 4s is cheaper for bashers too so higher Kv sells better. All else being equal (including top speed) a lower Kv with higher voltage will be more efficient than higher Kv and lower voltage. Motors like the 11xl needed to be lower Kv with higher voltage to pull around larger trucks like the LST.

The Losi mount has a 43mm diameter so it will take a Castle, Tekin or most any finned motor. But those fins don't contact the mount causing it to hold heat in, plus it's limited in its gearing. If you kept the Kv around 1500 you could run 6s (stock trans gearing) with the Losi mount, but 2200kv you would need to drop down to 4s to keep the speeds and temps in check. I wouldn't recommend the 11xl or similar 36mm motor in the Losi mount.