Losi LST #2 build

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have some of those (think the proline versions) on my MGT, was debating throwing my 17mm hexes on the MGT and using the PL 23mm adapters on the LST, or just get another set of 23mm adapters and get another set of 23mm rims and tires. i love the mashers, but not as good of grip as I've grown to like.
my only gripe with going 23mm is that it seems it is going obsolete for most of the newer tires. but lots of stock online though so i dont know if its enough to worry about.
 
not too much progress to report, got the screws i needed of the correct length, so have replaced the screws i had in to hold it together, got the upper hinge pin brace from my LHS, a stub axle, some misc hardware (5-40 screws are a PITA to find), and some clutch shoes and springs for the clutchbell, got some of the other pieces ordered including the shock hardware set and steering bellcrank assembly. its really weird being able to get parts ordered through my LHS, instead of everything being online only or NOS if they have it.

also ordered the flywheel kit (i had the flywheel with the purchase, but did not receive the nut), the missing turnbuckle, and the throttle brake linkage.
down to needing:
- transmission and 2 speed assembly,
- diffs front and read
- servo mount assembly
- servos
- tires and wheels, (atm have a set of T-maxx wheels and tires just as placeholders.)
- wanting to upgrade to RC Raven Springs probably order 2 sets.

still to decide on
- Steering setup- single servo setup? or stick with dual? thinking either getting some 20kg servo, or something at least 350+ oz/in torque spec, and converting to single, or get two (probably Hitec HS646WP or HS 5645mg) and go standard setup. i thik running dial super high torque servos would be overkill, and just drain battery faster and probably break stuff if any binds occur.
also just realized that the stock servos (ZR590M) only produce 85 oz/in of torque, which kind of surprises me for how well they work to turn this thing.
- engine - still indecisive on what route to go, see a few mach .26 engines for sale and have been loving that one so far, but kind of want to try something new out as well, including maybe a Novarossi truggy 28-8 possibly? right around 220$.
but i have time to decide.
 
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ur making me want another lst even more lmao
lol you know you want to! ;) few there on ebay, is an LST1 for around 230$, they call it an aftershock, but it is definitely LST1, has forward/reverse trans, with HI/LO, has blue shocks, and the blue head mach .26 engine. probably would have been cheaper for me to start with something like that or a roller from a few of the groups I'm in, but the build is just so fun and addicting.

i think eventually i am going to be updating to LST2 hubs, arms, axles, and carriers on this, either that or swap my other LST original components over, and have a true original LST1, and then build my other up.
 
bit more progress, had found a transmission online for quite cheap, it included everything on it, including the FOC, Brake assembly, and 2 speed/slipper assembly. was kinda cool because it had the TiNi Gears on it, but they are pretty rusted. will probably put plastic spurs on it as i dont seem to have problems with the stock ones, and i wont have to get the TiNi clutchbell as well. kind of cool to have though imo!

down to only needing a few parts including servo mounts, servo(s), and front differential. my LHS has an assembled one i believe for right around 50$, and i can buy a aluminum case for it, (still have a plastic case from when i swapped my other LSTs diff case out to Alu. after i broke one). or i could go to Jenny's RC and get one with driveshaft and case for right around the same price, but not supporting locally...
i do already have a driveshaft, but a spare would be nice.

side note: the one diff i did buy online through ebay (think it came from an RC chop shop as it was brand new) was really tight, i noticed as soon as i got it, so i tore it down but even with the shimms pushing the teeth away from each other as far as possible, it is still tight. bearings are good, just can't space the mesh far enough, hoping it might "break in" and loosen up maybe?
pretty worried about that.
LST #2 top view left front.jpg
LST #2 top view left.jpg
LST #2 top view right front.jpg
LST #2 top view right.jpg
lst #2 w body.jpg
 
Got the servo mounts ordered, forgot I had a Hitec HS645 on my Axial AX10 roller, made up a quick steering linkage, put the servo in place (no mounts yet so just floppy in there. Eventually going to buy another HS645 I think if I do feel I need more steering power.
Also got some Hot Racing Titanium axles, more or less because they were cheap, and atm I have 3 normal thread axles and 1 reverse, so would like all to be normal.
 
received the pieces Monday, was able to spend about 20 minutes yesterday to mess with it, realized that the JR servos have a low profile top to them, most others do not. so i will have to sand/grind some of the bell-crank and or shorten the servo mounts a bit. should only be a mm or so i think.
for now going to run it as 2wd as i do not yet have a front diff for. few on ebay I'm watching and hopefully soon will be ordering them. (weddings are really expensive lol)

going to need some more receivers as well, but for now think I'm going to just take one out of another rig for testing purposes.
need to figure out something with the roto-start deal, forget the HPI had a weird dogbone shaft, i might have a small enough dogbone, but concerned on length. ultimately would love to have a pull start, but finding the 12mm owb pull start assembly is proving difficult, and spending 60$ on the 14mm p/s and OWB is almost enough to just buy a new engine.

hoping to have the servo mounts filed down and servo installed today, can at least test my electronics and set EPAs and stuff (if i have time)
 
receiver came in last night.
test fitted the first servo, had to sand down the servo mounts to get the servos to fit beneath the steering bellcranks, they clear now but are very close and i think do touch, so might send down some more. (sanded down .5-.75mm already.)
tested the electronics and noted the single Hitec HS645 servo might not be quite enough, it was on carpet though with PL Big Joes, so kind of skewed results, but then also realized i had another Hitec HS645mg in one of my evaders, ended up pulling that one out of that truck for now, and repairing one of my other servos that had chewed wires and put that back in the evader for now (shortened the wires too so not miles of wire in the RX box.)

need a servo splitter cable now to test, and trying to figure out linkage, might just need to bite the bullet and get the OEM style linkage, but will see if it will work how i have it now.
worried about un-synchronized servos fighting each other.
I did order a 20kg 0.14sec/60Degree servo along with a few more RXs off amazon i might swap in and revert back to single servo steering depending how much i like the new servo and if it seems to be fast/strong enough. might swap my Hitec HS645s over to my other LST with OEM linkages and see how i like that. depending on accuracy of the amazon listing, will be similar specs between the two different setups. i really dont trust cheap electronics though, so this will be my first experience with cheap servos. supposed to be around 30$, but was on sale for 18$. time will tell.
 
was able to get the Y-harness last night for the servo, hooked it up, then set my horns on the servos and surprisingly only had to one of the links one full turn and no binding/fighting among the servos. seems to be plenty of power now with dual Hitec HS645s! should be 260oz/in torque.
i am using true servo horns in lieu of the servo savers, and using traxxas turnbuckle ends shortened down with a 15mm long grub screw threaded between them on both bellcranks. seems to be a really sturdy setup, very little play etc. i did get some items to make one more easily adjustable if need be but as the servos are not fighting at the moment i think it should be ok.
will try to get a picture.
EDIT: Added Picture
Servo Linkage.jpg
Servo Linkage2.jpg

i actually didn't have any standard servo horns, so i used an X-horn, and cut off 3 sides of the X.
after looking at the pictures i am realizing they really need a lot of cleanup! lol
but they have worked so far for testing purposes though and will try to file them down a bit to look better.
also noticing i forgot to swap out the chassis rail screws to be all silver.

still need to swap spur gears though, dont want to mess up the clutchbell from the hardened spurs.
now just to wait on the weather to clear up a little and then can take it for a test run.
 
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if anyone is planning on doing this to their own truck, or another truck in a similar configuration, i really am hesitant to recommend using the linkages like the above, unless you have easily adjustable 15-18mm turnbuckles to adjust the steering link length. what i am using is just a grub screw so there is no reverse threads, meaning i am limited to either 1/2 turn and full turn adjustments.
something like this:
https://www.ebay.com/itm/3Racing-64...0-RC-Car-On-Off-Road-3RAC-TR315-/381264059368
i can't stress enough how hard it is on the servos to be constantly fighting each other most likely resulting in damaging them both.

or going in the direction of a single servo setup.

do have a question for those that own/have owned an LST, do you guys recall the Bad Ass Creations steering link kit? anyone get/use on?
 
if anyone is planning on doing this to their own truck, or another truck in a similar configuration, i really am hesitant to recommend using the linkages like the above, unless you have easily adjustable 15-18mm turnbuckles to adjust the steering link length. what i am using is just a grub screw so there is no reverse threads, meaning i am limited to either 1/2 turn and full turn adjustments.
something like this:
https://www.ebay.com/itm/3Racing-64...0-RC-Car-On-Off-Road-3RAC-TR315-/381264059368
i can't stress enough how hard it is on the servos to be constantly fighting each other most likely resulting in damaging them both.

or going in the direction of a single servo setup.

do have a question for those that own/have owned an LST, do you guys recall the Bad Ass Creations steering link kit? anyone get/use on?
This guy had it back in the day:
https://www.rctalk.com/forum/threads/my-lst-2-build.59566/post-592967

I may have had it on my aftershock... can't recall. I don't remember the significance of it. I always ran smaller tires/wheels on it than stock and I stuck with the stock Z590M servos I think. Funny to think how many 250oz+ servos exist now for a very low price compared to back then... wasn't the BAC link used when you ran a single high power servo? Or was it still intended for use with dual servos?
 
This guy had it back in the day:
https://www.rctalk.com/forum/threads/my-lst-2-build.59566/post-592967

I may have had it on my aftershock... can't recall. I don't remember the significance of it. I always ran smaller tires/wheels on it than stock and I stuck with the stock Z590M servos I think. Funny to think how many 250oz+ servos exist now for a very low price compared to back then... wasn't the BAC link used when you ran a single high power servo? Or was it still intended for use with dual servos?
haha yup have his build bookmarked for reference if i need it thanks! that vantage pipe he has makes me very envious lol.

Many people (at least in the race world) were having issues with the steering links breaking/bending from what i have read, with doing both single servo and dual servo configurations.
I'm more or less curious because the fabricator of them "AKFireMedic" in his thread on RCU described it as having a second peice of wire welded on the length of it. as well as in his pictures, but looking at others and like in the thread above it seems to be a single length of wire, just curious if the design was changed as the second length of wire was unnecessary or something.
also was curious what the final length of them was if someone on here still had one.

It is very strange how cheap powerful servos are nowadays, i remember only a few companies made the really high torque 250oz/in servos and those were typically over 100$ a pop! now you can get them for right around 20-30$!!!
 
small update,
still havent been able to run the truck, and still no Diff for the front. (pending shipment/delivery)
from the new MMGT package, a HPI F4.6 engine was included by @Mr. block , and was in alot better shape than the HPI .25 engine i had mounted up, he also had included a pipe for it too so i installed that as well. very excited to get this thing out and run it! engine still does have some pinch so i am going to pre-heat before firing it up.
got a RX battery, so installed that as well.
LST w 4.6 left side pipe.jpg
LST w 4.6 right side.jpg
LST w 4.6 underside.jpg
 
One thing a lot of guys did was drill out the upper shock mounts/tower and use 4mm bolts as the stock bolts tended to snap off.
 
One thing a lot of guys did was drill out the upper shock mounts/tower and use 4mm bolts as the stock bolts tended to snap off.
thanks for the info, going to look into doing that. 5-40 hardware sure is a PITA to find locally at the moment i think i actually have a 3mm screw on the one, but is slightly smaller than 5-40 i think.
 
Yeah, I replaced all the 4-40 stuff with metric when I had mine. Was annoying trying to keep the screws straight between that truck and all my others that used metric.
 
so far just the shock tower screws, engine mount screws, trans mount screws, and engine brace screws are all thats left being SAE. all those require some modification to be metric and just haven't converted them over yet.
 
took the truck out today, had a few minutes between rain/hail spurts, all i can say is man this truck has some power.
truck is still 2wd at the moment and i still had it running pretty rich, but popped up on its rear wheels in first and definitely did on the 1-2 shift. definitely surprised me the first time. was just starting to get it close to tune and hit powerband when weather started getting less than desirable.
that JP-3 pipe sounds really good and from what i can tell compliments the engine well.
(eventually going to swap back out to stock pipe and see what difference there is.
A bit skeptical as the truck is still only running 14mm hex wheels, might have to swap engines to the .26. my thinking is it doesn't have quite as much torque, so wont have to worry so much about stripping wheels or hexes, might be overthinking that though if i just make sure to keep the wheel nuts tight?
thoughts on that are greatly appreciated.
steering is definitely very strong with the duo servo setup, even with the "Custom" servo horns and links lol.
realized when i was at the hobby shop i grabbed two "First/low gear" spurs, instead of a first and second. need to see if they have any 2nds left.
 
Kind of funny, the first hex I ever spun out was a 14mm on my aftershock. They were smaller t-maxx wheels though.

I spun one out before that, but it wasn't from driving it, it was from trying to remove the cross threaded wheel nut.
 

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