Which MT parts break first?

[Smirnoff]

I'm very close to placing an order with Meganitro.com for an MT Racer. My intentions are to do what I assume is normal MT bashing, small jumps, running over grass and generally going places that my RS4 3 cannot go. I'd also like to stock up on the most frequently breaking parts, could someone tell me what these are?

[robstoys racing]

on my NMT, the only parts i have ever had a real problem with breaking are the outdrive cups at the differentials.

Replace them with the RUSH units or hardened versions and the problem goes away. the stock peices are very "soft" and wear out or snap after rugged use.

other than that, you may want to add an aftermarket uppder chassis plate (you lose the ability to quickly remove the radio tray), but their is a rather fair amount of flex in the chassis, and an aluminum top chassis plate virtually eliminates the flex all together and makes for a much more consistantly handling truck.

[Smirnoff]

Thanks robstoys. The outdrives are added to the list and the search begins for an upper tray. I'm not to worried about losing the removable tray functionality, I was on my RS4 3 but once I'd installed the HB CF upper deck and could see the benefits I soon forgot about removing my radio gear :).

What about a-arms? Do they last or should I get a couple of sets of those too?

List any essential hop-ups too. I'm not aiming to get a the fancy Alu thing going on with the MT, I want to be able to abuse this truck (within reason) and not have to worry about scratching this and permanently bending that.

[Nitro-PuPpy]

I'd definately get a couple of spare "A" arms, the tree you need is part no. A456.

I think the "A" arms are stronger now than they were initially, but I'd still get a couple of spares. Boil them too, for about ten minutes, stress relieves them or some such technical jiggery pokery :D

In the meantime, here's a couple of action shots to whet your appetite for you coming truck !

Nitro_PuPpy

http://www.scinet.fsworld.co.uk/flight.jpg

And..... weeeeeeee !!!

http://www.scinet.fsworld.co.uk/flight2.jpg

[Smirnoff]

Hehehe, that looks cool. I can't do that with my RS4 3!!!

[ally_rules]

Out grives haven't been a problem 4 me and mines a .21MT and I jump just about anything.

The thing i break are ball-ends(Z136) but i'm getting Ti ones now.

A-arms if you've got the money get alloy ones.

Spur gears-if you're making a big order u might aswell get some spare spurs.

Oh and don't forget your fuel filter.

You might want to get a bumper. You could make one yourself or buy an alloy one which will save some parts from big crashes

Hope this helps
Paul

[Smirnoff]

Thanks for the suggestions. I'd have thought Alu a-arms would be a bad idea on a stadium truck, or haven't you had problems with them bending?

Stuff like fuel filters and so on are no problem, I've already got a couple of spares lying around, I've got a Sulivan double screen filter which is now earmarked for the MT.

Who makes the best bumpers? I think (???) I've seen yours, didn't you make it yourself or have I mixed you up with someone else?

[ally_rules]

I have ally arms all round and i've had no probs with them even with full on crashes.

Yes i did make my bumper AFTER my bought ally snapped.

Just don't get GPM they have a Z/N cut in the base and it weakens it serverly.

Here's a couple of my bumper mods.

[ally_rules]

and some where else

[Smirnoff]

It looks good. I'm hoping to avoid catching the hopup bug with the MT, I'm still realing at the thought of how much I've spent on the RS4 3, its got just about everything including rush outdrives, mips cvds, alu hub carriers, centre bulkhead, lower front and rear bulkheads, CF shock towers, CF upper deck and an F4i racing Ti upper deck, two speed with Wolfgang's shoe type conversion, digital servos and more. I want to keep the MT simple, sweet and cheap but if ruggedness suffers from certain stock parts then they will be replaced.

[ally_rules]

all i did was replce with alloy when the stock parts broke......

.........thats what i did all-over.....

....FE wasn't started- converted to .21

....ballends were breaking - got Ti ones, and Ti turnbukles at the same time( still haven't come)

.....a-arms broke- got ally one alround, and got the ally bumper and F & R ally shock towers to make up a good order, from the US.

......First radio i got 4 it was the KO EX-5 master radio set.

......spurs were breaking- got a slipper clutch.

I reakon from last November when i got the MT i've proberly spent £800-£900 on my MT

[Smirnoff]

The good thing about doing this, especially with a Racer from a friendly dealer in the States, is that its cheap and all the extra parts needed to get it running are here waiting to go into it. I think its a better choice to buy the car to use up all the spare stuff than to sell the spare stuff at a knocked down price or let it go to waste. This is how I'm trying to pitch it to my girlfriend anyway ;).

[ally_rules]

When i need to get rid of some thing i stick it www.ebay.co.uk or www.rcauction.co.uk rc auction is pretty much free, and you can sell things better.

[Smirnoff]

Yeah, I've used e-bay loads of times but I don't want to sell these bits and pieces. I lose less by keeping them but putting them to use. Lets change the subject before a mod gets the wrong end of the stick and tells me off...

For general jumping around and stuff, what springs do most people use? Are the stock ones okay? What coloured spring do the stock ones equate to?

[ally_rules]

I use blue springs and F yellow springs in the rear together.

and in the front i use the rear stock ones with 2 large spacers.

[Smirnoff]

So you've got a dual shock conversion at the rear? Do you have to buy these or does the stock setup allow for this? Obviously you have to buy another set of shocks right?

Can you do dual shocks at the front too?

Or do you mean that you've got two springs on on shock?

[Smirnoff]

Okay guys, tell me which to get... Titanium upper deck or HPI's graphite upper deck?

[NMT_Oli]

definately go for the titanium upper deck!

IMO aluminium arms are a bad idea! they trnasfer the stress to other areas of the car. i like to keep the plastic ones as a weak point as they are easy to replace and cheap. i have only broken 3 (in 3 years) any way.

you can put dual rear shocks on an nmt. i cant any more cause i havea .21 conversion but i used to have them. i am usingthe stock springs at the fornt and the ones that came wit my hotbodies shocks at the back with 20wt oil. this allows for very good supple suspension but you may want to set it up a bt harder for large jumps, my nmt handles bmx track jumps very well with this set up.

As allyrules said, ti ball studs are very good, im awaitng mine at the moment. with stiff turnbuckles like Ti they snap very easily. you may wnat to consider an alum or Ti fornt shock tower as the palstic one is quite esy to break. you can strengthen it by putting a brace between the screws, it worked for me!

Drive fast, Have fun!

Oli

[Smirnoff]

I would tend to agree with you about the alloy a-arms. I've decided to go Ti, just placed an order now, for front and rear shock towers and upper deck.

Did you go with Titanium Racing's ball studs or the HPI's Ti ones?

Are the super shock set worth getting or do you think that they are just eye-candy?

Thanks for all the input so far guys.

[NMT_Oli]

i found the caps on the stock shocks pop a lot, but dont get hpi super shocks as they are very expensive! i got hotbodies purple threaded tmaxx shocks (alum) for $20 a pair of tower, amazing for the money.

good choice on the upper deck and shock towers

i am going to be using Ti racings ball studs, i didnt know hpi made Ti ones!

Oli

[Smirnoff]

I think you're right, I was mixing them up with screws probably.

Thanks for the tip about the HB T-Maxx shocks, I definately prefer threaded over collared shocks. I notice that HPI have front and rear shocks, are the HB ones universal?

[H-Trainer]

Essential upgrades: Kimbrough servo saver, Motor Saver air filter, fuel filter, thick fuel line, spur gear protector (not exactly an upgrade, but necessary), silicone shock oil, shims for final gears and differentials, T-Maxx manifold, strong radio tray, thicker chassis, ...and so on... and so forth.
Visit my website -> Super Nitro Rally -> SNR Modifications for more ideas.

Have a few suspension arms ready, that's the first part to break in a major crash. I don not recommend replacing them with aluminum ones, because other parts will break instead and the aluminum can bend.

If you get an upper deck, get one that replaces the removable radio tray, or make one yourself, like I did.

[ally_rules]

Originally posted by Smirnoff
So you've got a dual shock conversion at the rear? Do you have to buy these or does the stock setup allow for this? Obviously you have to buy another set of shocks right?

Can you do dual shocks at the front too?

Or do you mean that you've got two springs on on shock?

I would love to have 2 shocks on the back but all i've done is put 2 springs into one body to stiffen it up.

I have a .21 so I can't have 4 shocks on the back any way.

How much is a set of HB shocks.

[Smirnoff]

You'd class a thicker chassis over the MT Racer's Super Chassis as an essential upgrade?

Everything else bar the shims and the T-Maxx header (which can wait) has been ordered. I'd already gone with your recommendations regarding Sulivan fuel filters, as mentioned earlier.

[Smirnoff]

The HB shocks are $20.99 a pair. Does anyone know if these are suitable for the front shocks? I've had a look at the specs on Tower and it doesn't give details of the shock's travel.

[ally_rules]

I wouldn't class a thicker chassis a must have..............

I've been running my MT with the stock chassis for 1yr now and no bends or anything.

You can get a 4.5mm chassis from Mega tech.

[ally_rules]

Originally posted by Smirnoff
The HB shocks are $20.99 a pair. Does anyone know if these are suitable for the front shocks? I've had a look at the specs on Tower and it doesn't give details of the shock's travel.

He uses them on the front

http://forum.hpi-europe.com/showthread.php?threadid=2592&goto=newpost

and thats how he does in his latest post

[Smirnoff]

Thanks, I started to get confused then, I tried searching and failed to come up with an answer, but its because I searched much earlier this morning :(.

Well I think I'm just about done now... spent enough already!!!

Thanks for all the advice guys, its much appreciated. Here's what I'm having:

MT Racer.
Lunsford Titanium Turnbuckles/Hingepin set.
RPM Heavy Duty Ball-ends.
F4i Racing's Titanium Upper Deck.
F4i Racing's Titanium Front Shock Tower.
F4i Racing's Titanium Rear Shock Tower.
Hot Bodies Threaded T-Maxx shocks (3 sets).
Motorsaver Off-road air filter.
Rush Shiny Outdrives.
Sulivan Double Screen Fuel Filter.
Titanium Racing Ball Stud Set.
2 sets of a-arm tree.
Kimbrough #124 Servo Saver.

Still got to decide what I'm doing about shims and will possibly look into making a front bumper myself. Got to choose a better brake disc also.

I might sift through the manual later and order the relevant screws from Titanium Racing too, depends...

[H-Trainer]

What engine and pipe will you be using? What tires and gearing? With or without slipper clutch.

The stock manifold is very restrictive, a T-Maxx header or even a bigbore header will increase engine's performance noticably, say acceleration and top speed increase, engine breathes better.
The racing clutch is an important upgrade, too.
If you have the HD chassis, that'll be all right. I have the standard one and the engine and center gear carrier move when I apply the brakes :( I won't upgrade to a HD chassis, the twice-as-thick-as-stock all-in-blue Goldorak is my preference :)

On the Racer, the final gears have a shim, but another (if needed) doesn't hurt. After I shimmed my fianl gears and diffs, they weren't running smoothly, but after some break in, they're really smooth now and I hope they'll hold up to the OS 15 CV-RX's power output.

*edit*
For a better brake, I recommend the Kyosho MP-6 metal brake disc set with two brake discs, four pads. You need to use the HPI brake plates. One brake disc provides more braking power than the tires could bring to the ground.

You don't need a bumper if you don't crash frontally into immobile objects or land nose-down after jumps ;)

However, this is a list of my SNR Upgrades: H-Trainer's SNR Upgrade List (http://www.stud.alte-kanti-aarau.ch/~webth00f/H-Trainer's%20SNR%20Upgrades.txt)

[Nitro-PuPpy]

I think the racer comes with a slipper clutch as standard, my m8's has one anyway :eek:

That looks a l-u-r-v-e-l-y spec NMT Smirnoff, I'm jealous !! :D

Guess you are importing the Racer ;) If HPI won't let us have 'em here in old "Blighty" then desperate times need desperate measures eh. Tee hee.

Nice 1

PuPs

[Smirnoff]

>> What engine and pipe will you be using? What tires and gearing? With or without slipper clutch

I've got a Wasp coming for my RS4 3 so I'm taking the FE out of that. I've got the SS header to use with it, don't know if that's even worth mentioning, but there it is! I don't want anything high powered to begin with. I simply want something I can have some fun bashing around here with, I'll make a couple of jumps and stuff so that if I don't have time to get in the car and drive somewhere I don't really have to.

I'll be using with a slipper clutch. This thing is hopefully going to be airbourne most of the time :D.

Stock tyres and gearing to begin with.

I've got a spare racing clutch here that I'll be using.

>> twice-as-thick-as-stock all-in-blue Goldorak is my preference

Sounds like a tough one, I'll take a look later.

>> land nose-down after jumps

I haven't driven a car with any real jumping ability so I expect a few nose-down landings to begin with, and wouldn't want it any other way :).

My next todo was finding your URL and taking a look at the shim mods and whatever else.

[H-Trainer]

My URL is www.H-Trainer.ch.vu , you find the link at the end of my post, too, as well as in my profile ;)

I forgot to answer your original question, what replacement parts to stock. A 52T spur gear (for 2-speed, fits the slipper clutch, I believe) and a few suspension arm sets are what is most likely to break, besides normal wear and tear like outdrives (Rush), dogbones, and final gears (depending on shimming skills, slipper clutch tightness, and engine's power).

For the stock tires (Dirt Hawgs), I recommend belting them with fiber glass cloth and CA glue to prevent ballooning.

For jumping, you just need to start off small and hold throttle a little while in the air. When you go bigger, give throttle to bring the nose up or brake/let off throttle to bring the nose down.

[Smirnoff]

>> I recommend belting them with fiber glass cloth and CA glue to prevent ballooning

I'll give that a try. Anything specific tips on how to go about this, your site doesn't go into any detail on how you accomplished this. Do you drench the cloth in CA glue once its inside the tyre? Or do you strategically place drops here and there? Let me know, I don't want to ruin a perfectly good set of tyres.

I've done something similar with a set of tyres from my Nitro 3. I used thick surgical tape wrapped around each tire twice, this stuff is super sticky so there is no need for gluing. Seems to be working really well so far.

[H-Trainer]

Originally posted by Smirnoff
... Anything specific tips on how to go about this, your site doesn't go into any detail ...

I just cut the fiber glass cloth into stripes of ~2cm width and 5-10cm length (long ones are difficult to place precisly), put them into the tires, centered, and drenched them with CA glue to glue them to the tire compound.
If you intend to go very fast, using wider stripes may help. When I tested mine under high rev, the middle of the tires didn't balloon any, but the sides did a little (there's only fiber glass centered in the tire).
To make sure we're talking about the same (fiber glass cloth), see my picture on the "SNR Mods" page under "Glass reinforced body".

I'll add more specific information to my Mods page when I have some spare time (pretty rare recently).

*edit* I've updated my SNR Mods page, added that "How to belt your tires" information.

[Smirnoff]

Sounds good, I'll be sure to do this to my tyres. Thanks again everyone.

[AllenJO]

Essential spare parts, IMHO:

1.) front A-arms. Stick with plastic and boil them (as HPI recommends).
2.) spare screws, especially all that fit in the bottom of the chassis.
3.) diff gears
4.) ball bearings -- 5 x 11 (wheels) and 10 x 15 (diffs)
5.) diff outdrives and axle outdrives -- they will wear out over time.
6.) body clips
7.) lug nuts for your wheels
8.) hinge pins
9.) E-clips
10.) dog bones

[H-Trainer]

Originally posted by AllenJO
...3.) diff gears...

Do you mean the final gears or the differential bevel gears? :confused: If you mean those in the diffs, get Nitro 3 ones, they're stronger. Shim all gears as necessary.
Funny thing about the screws, guess you have to retighten them between every couple of tanks.

[Smirnoff]

Both the spider/bevel gears for the Nitro 3 and the HD final gears were on the order. I'd rather put these in from the start.

The hingepins are taken care of by Lunsford. There are no dogbones going into the truck, the Racer has CVDs and I've ordeded the centre universals. I'm not too concerned about parts that wear over time, more things that somebody not used to jumping will break frequently, besides the Rush outdrives should last a little longer than the stock or HD ones. The rest are just sundries that I've got plenty of anyway.

There are plenty of the washers that are used as shims coming too, so I can put my 'shimming skills' to the test.

[H-Trainer]

Originally posted by Smirnoff
...the HD final gears were on the order. ...

Front and rear? Man, you have way too much money on your hands! ;) One set of HD ones is six times (!) the price of regular ones. Well, I hope I don't have to buy them, hoping my shimming skills are good enough ;')

Smirnoff, you'll have one bootie-kickin' NMT there! With the suspension and gears set up right, it'll run like a dream (for this class, of course, not comparing to MT's, 1/8 buggies, or so ;')

[Smirnoff]

>> Man, you have way too much money on your hands!... my shimming skills are good enough

LOL... I was wondering, could I pay for you to come to the UK for a day or two in return for 60 minutes of your time to do my shimming to perfection for me???

<whispering>I'd better not tell him that the order included another front and rear set of HD final gears for my Nitro 3 and new spiders too (ooh the cost of these spiders is way too high ;)).</whispering>

BTW... SN VipeR and H-Trainer (and everyone else), you really should be speaking with meganitro.com when you want parts. On this order $600 he was $110 cheaper than Tower and he is 'international customer friendly', now you are both intelligent lads and can see what I'm trying to say here!

[Smirnoff]

Besides, if I did have too much money, I'd be buying a Sandwich, err Savage! (no offence, in relation to a joke I picked up on between you and SN VipeR before)

[H-Trainer]

Originally posted by Smirnoff
...could I pay for you to come to the UK for a day or two in return for 60 minutes of your time to do my shimming to perfection for me??? ...

Sure, I have time between christmas and new year, or whenever you want! I'd even clean your car ;)
BTW, the perfect shim is always too tight in the first run, but after you broke them in, they'll run smoothly and be able to transfer more power without stripping.

I'll look into that website. Yeah, I know what you mean.

Careful reader, huh? Just have a look at the HPI .21 Monster Truck and tell me what the two plates with stuff in between look like. *hint* it looks like a Sa###i## ;)

[Smirnoff]

All becomes clear now!!! The site doesn't show that much, but he does stock nearly every HPI and Hot Bodies part, send him an e-mail (lance.bingham@mindspring.com).

[AllenJO]

H-Trainer:

I meant final gears. Have heard that the RS4 3 bevel gears are better and they look it. Would agree that there is no need to put HD final gears in the front diff, but I think they are worthwhile in the rear if you're running off-road and do a lot of jumping -- and if you have the money. With my NMT, I was chewing up final gears in the rear on a regular basis, even after shimming. No more though with HD gears. (Despite saying this, at one time I was flush with cash and put HD gears in front and rear.)

Also, in the US, Great Lakes Hobbies sells the HD diff gears at about 2/3s the cost of HPI and Tower.

Don't know if HPI does this in Europe, but in the States HPI was offering a free exchange for stock final gears -- free for the cost of mailing the gears to HPI. I have 4-5 sets in my parts bag gathering dust.