kantfunkshin

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Well I think I have finally decided on how to paint my next MT body. I might use a Inca paint mask and go with a candy apple red for the major parts and the holographic paint for the Inca designs themselves. Any input from anyone will be considered and appreciated. Here is a pic of the paint mask that I might use (I got the pic from Tower Hobbies website).

tcoop25

Hey everyone, parts are slowly coming in for my MT1 rebuild. I picked up a G3.0 a few weeks ago, and have since gotten a new gas tank, new fuel lines, and a new fuel filter (a new exhaust pipe is coming soon). I just bought a full MT2 clutch setup off ebay (flywheel, clutch bell, shoes, spring, bearings, etc). Should I keep the wrap around spring, or go with the 2 spring setup with teflon shoes?

Also, I was told to get new hardened diff gears. Which gears should I get? Will the MT2 diff gears fit inside my MT1 diff housing?

Thanks,

-TC

MattVid

My Feedback: (1)

I would say go for some chamelon/halographic paint on the body. Then try to do those designs in chrome. That would be awesome, but hard possibly. I am not a huge painter, so I don't really know how to mask and stuff well. Do you actually cut out the pieces of paper and glue/tape them on the body to mask it? I would like to do a more intricate design sometime.

And I need to post new pics of the body, when I took the plastic off, it looks amazing now. Much more glossy and poppy. I will be curious to see your paint job when you get underway, I know mine was simple, but an experiecne

MattVid

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I am relatively new to all this, so I am not sure what a "wrap around spring" is for a clutch. I am using the standard 2 clutch shoes that came with the MT2 18SS, and they seem to be working fine with my OS 18 CV-R ... it flies, and gets off the line well.

For the diff gears, you want the hardened steel ones, that come in the 18ss+ kits. There are some people on eBay that part out the kits, so you should be able to get some there. I actually bought some aluminum diff boxes (instead of the plastic) and mine seem to be holding up well. And I don't have hardened gears. The aluminum doesn't give/bend/torque around as much as the plastic, allowing the gears to stay threaded better.

I will get the hardened gears once I strip my current ones out, but there is no point in replacing something that isn't broke

kantfunkshin

My Feedback: (8)

I use pre-cut masks since I dont have the skill yet to make my own. The pre-cut masks are like a vinyl sticker that you place where you want on the body. There is also a liquid mask that you brush on then cut out your own designs after it dries then just peel it off, but I dont have the skill to do that yet. Maybe in a few bodies I will try that way along with some airbrush practice.
I am picking up a body today and hopefully the paint if they have the ones I want in stock at my LHS. So if all is in I should have pics by tomorrow.

MattVid

My Feedback: (1)

Ah I see. I thought you printed that sheet off or something, but you purchased it. That is cool, I might try looking into something more intricate next time. Honestly, my body is going to get trashed anyways, so I don't really like spending loads of time making it look perfect.

My last body on my old electric car was fully lined with duct tape. I did so many ridiculous jumps with that thing. It will be just a matter of time until I see how much punishment the MT2 can take

MattVid

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Hey guys, I had a quick question about engine tuning. I was doing some speed runs yesterday to try to get my engine tuned up, and leaned out the HSN so the engine runs anywhere between 185/190-220 (depending if I am flooring it, in the grass, or going medium speed), should it be running hotter?

The car seems to be really fast, as I am not used to the speed, so I am mainly going by temperature and sound of the engine (and visible smoke). After I ran a tank of fuel through it, I brought it back inside and started cleaning body and shocks out a little. I turned the car upside down and some gas dripped out of the pipe. This makes me think it is running too rich? It wasn't a lot of gas, but is this normal?

Overall, the acceleration and top end speed seem pretty solid. I am no pro-racer, so it is kind of hard for me to tell when it is perfect ... I just want to make sure I am not doing damage to my engine by not tuning it right.

One more thing, when I go WOT and then let off the throttle, I get a sort of gurgling "brrr brr brrr" sound as it slows back down to idle. Would this be something pointing to a rich mixture? I probably need to adjust the LSN some, as I haven't touched it much yet. Any insight would be helpful ... off to read some more tuning guides to see what they say :P

SAVAGEBANE

so, I was able to get the MT2. took it all apart to clean it up and check it out. took the hpi .15 motor off and cleaned and sealed the carb, new clutch and springs and also put a gasket on the manifold. when i start it up it is exactly as the seller said. it starts up fine and then gradually goes into max rpm before it shuts off. If i am quick then i can hit the brake to reset the revving. i have to continually feather the throttle to keep it running while tapping the brake every 3 seconds to stop it from getting to max rpm.
the HSN is flush and so is the big screw on the side(LSN?) however, about the small screw that is spring loaded on the front of the carb(idle screw?) i dont know whether it should be in or out or in between. the return spring seems to be doing its job.
does anyone know where the idle screw should be set?

MattVid

My Feedback: (1)

So are you sure you are not getting any air leaks now?

If the engine is reving up to high RPM's it sounds like it is getting air from somewhere. You are saying that braking makes the RPM's drop? What is your carb set on when it is "neutral" (you are not touching the trigger)? Your idle screw should be set so when the carb is "closed" (which is neutral/braking position), you have a 1-2mm gap. You can easily adjust this when running as well, if it is set too high/low.

The idle screw doesn't sound like the problem. It sounds like your carb is seriously malfunctioning or you have an air leak somewhere. Are your fuel lines crack free? Have you tried replacing those? I am not an expert, but it sounds like you are having some kind of air intake issues (you are getting too much air).

You could try richening the fuel mixture a lot, to try to lower the RPM's down. I have not experienced a problem like this before, just trying to reason through it some, hopefully others can throw in some advice. A more detailed explanation might help as well. Like is the engine only running for a few seconds? A few minutes? Define "gradually reaches max rpms". And by max, you mean it is really WOT? Again, it sounds like major air leaks ... as in, a wide open carb full of air leaks.

SAVAGEBANE

thanks for the reply. To clarify, i mean that when the engine starts it idles for 2 seconds and then it sounds like it reaches WOT within 2 seconds.It stays at WOT for a second and then shuts off. if i wanna keep it running then i hit the full brake for a second and it drops down the rpm....low enough to make it shut off if i dont start feathering the throttle again. with the car off the throttle linkage works well, although the closed position is probably more than 2mm. i will change that tonight.
As far as the air leak is concerned, i have sealed the carb at the neck and also the header(probably not necessary) where else could this possible air leak problem be coming from? the fuel is as rich as possible, HSN is flush. no cracks in the fuel line or tank but i will double check.
i will try to do a video tonight but its always dark when i get home.

kantfunkshin

My Feedback: (8)

Hey Savage, It sounds like your idle set screw is adjusted too far open. Try closing the screw a little (the one under the aircleaner) so it doesnt rev like it is now. If it stalls when that is adjusted but it doesnt rev high then you might have to lean the LSN (the screw facing the muffler). Try it in that order first-Idle screw then lean LSN (if needed). I hope this helps you.
Here is the nitro star .15 manual from HPI. I also got mine used and it didnt come with the engine manual so this came in handy for me.
http://www.hpiracing.com/graphics/in...5101-2%20S.pdf

kantfunkshin

My Feedback: (8)

I also have a little gas coming out of mine, but as long as it isnt a big amount (stream) and just a few drops it should be fine. After getting advice from others here (also fairly new myself to nitro) about tuning they said some engines might run hot but as long as it is tuned so there is the right amount of smoke and the engine sounds right it should be fine. Just keep an eye on the temp so it doesnt get WAY too hot and just adjust from there if it does. The manual for the .15 looks to say the safe range in between 200-260F.

Not sure about the "brr brr brr", but I am thinking it might be too rich on the HSN since it happens when slowing down from WOT. Again im not sure so hopefully someone with more experience can help. Not sure which engine you have but if you have the .15 I posted in the above post the link for the engine. Hope this info helps you.

MattVid

My Feedback: (1)

Your carb idle screw setting has to do with the car shutting down when you apply the breaks. You need to make sure you have more of a gap when the brakes are applied (and should also be at the same setting when in "neutral"). But if the engine is also shutting off when it starts reving up, that smells more like an air leak to me.

What could be happening (assuming your engine really is hitting WOT somehow), is air is leaking into the engine from somewhere and mimicing a "fully open" or "mostly open" carburettor. All that regulates engine RPM's is the amount of fuel to air intake, well the things we can actually control (needle settings and carb opening). So if a ton of air is leaking, or getting into the engine (due to bad throttle linkage operation or actual air leaks) it will rev up. If it is seriously hitting the max RPM range, you are technically "leaning it way out", to the extent that it will shut off ... that could be a possibility.

Other places to check for air leaks would be the back plate of the engine (the plate behind the roto start, or pull start). Might be worth making sure that any o-rings are in place on the back plate and go ahead and seal that up.

First I would adjust your idle screw so the engine (hopefully) doesn't shut off when in idle/braking. Then reseting the HSN/LSN needles to the HPI factory settings (from the link kantfunkshin posted), and trying again. Running too lean, or too rich you can get stalling/weird behaviour. If you want to check out he air leak stuff before, or after you do the first two steps, go for it, but looking at that back plate for o-rings/gaskets would be a good idea, and seal it up for good measure.

I will try to look up some more stuff on this issue and let you know if I find anything. Hopefully one of the "pros" will get on and shed some light on this topic. Hope you get up and running soon!

nitro-rob

Savage,
I had a problem like that once and there was an internal problem with the needle that forced too much fuel in the carb. The engine would start but when fuel pressure almost immediately got built up it forced too much fuel in the carb and rev too high but it wouldn't have enough oxygen because the carb wouldn't be open enough and it would cut out. The high speed needle wasn't in far enough although it looked okay from the outside making it not restrict fuel flow. I don't know if that is your problem, but it had the same symptoms.

MattVid

My Feedback: (1)

Yea, I am thinking it is possibly too rich still, but temps are about at nominal. The gas that came out of the pipe was probably about a teaspoon's worth, not a ton, but noticeable. I have the OS 18 CV-R engine, I will try leaning it out some more and see how that goes.

As far as the noise it is making when slowing down to idle from fast speeds, could this have anything to do with a rich setting on the LSN? It is approaching idle when making the noise, or the carb at idle but still moving quickly. It is odd, still trying to figure out how to tune it properly, but I am getting there slowly ... and I haven't broken anything yet, so that is good

ace9213

How do you guys like your mt2's? I think I might want one. Are they fun cars? Are they durable?

KeithjV

WOW that was a lot of posts to read in a short time..
OK, as Matt said check all the fuel lines for holes and leaks. Check your fuel tank as well. It sounds like the engine isnt getting enough fuel. Thats why the rpms shoot up and then it dies out, just as it would when the tank runs empty. Try turning your LSN counter clockwise one full turn. Take your air filter off and adjust the idle screw so that gap is about 1mm. If the HSN is flush with the casing that should be ok. Try restarting the engine and see if you can get it to idle. Also, is the CB spinning when the engine is running or just when the RPMs come up?
What kind of fuel are you using and how old is the engine?
Usually after running you will get some oil and a little bit of fuel spilling out of the pipe. A little bit is normal and is usually from running a little rich. A LOT of fuel is a problem. Just remember its better to run too rich then too lean.
When tuning you can keep turning the HSN clockwise 1/8th of a turn at a time till you dont see an increase in performance anymore, or the temps start to get too high. Then turn back 1/8th. Then adjust the LSN to improve throttle response off the line.
Once you have the truck tuned the way you like you can check your needle settings by doing a pinch test. With the engine idling, pinch the fuel line about 1 inch from the carb. If the engine takes the 2-3 seconds to rev up and then die you are running pretty good. If the engine immediately dies you are running too lean. If the engine takes a long time to rev up and then increases RPMs a lot before dieing, you are running too rich.

KeithjV

ace its a great truck. Its as durable as any other RC and there are a ton of hop ups available for it. If you have the chance pick one up.

ace9213

where can i get upgrades for it? what is the cars weakpoints? if i do get it i wont run it too hard at all. im pretty easy going.

KeithjV

The weakest point is probably the diffs. Upgrade them to the hardened ones and you'll be fine.
Upgrades are all over ebay and the web.
And Im sure you'll be running it as hard as everyone else once you get going..

kantfunkshin

My Feedback: (8)

Sorry Matt I was thinking the noise was soon as you let off the trigger from WOT. Since it is near idle when it does it I personally would lean the LSN a little.
And take Keiths input for tuning to correct settings.

MattVid

My Feedback: (1)

No, you are right, it is right after I take my finger off the throlle. It is hard to describe, but when you remove your finger from the throttle, the engine is technically in an idle state, as the carb is "closed", however, I guess the clutch would still be engaged thus making the engine still turn (because the wheels are still turning fast)? Maybe that is the noise I am hearing?

It basically sounds like a weak jake-brake, if you know what that is. Like when a semi is slowing down, they use the jake brake to help, which uses engine compression release, I believe ... and it makes that loud "bwaaaagaaaaagaaaaagaaa .... aaaah" sound as it comes to a stop.

Kind of hard to describe, but it might just be normal. Being that diesel engines and nitro engines operate similarly, maybe I am getting a sort of Jake-brake effect on the truck ... NICE!

And ace, the MT2 seems like a solid truck so far, this is my first leap into Nitro with the MT2 and it has been pretty smooth. I have already been bashing pretty hard and have not had any problems. Once I get my new shocks in the mail, I will start jumping it harder, so we shall see how it holds up. So far, I am nothing but happy with it.

I would say the only problem with the MT2 is it is a discontinued model, and not a lot of LHS support it anymore. But there are still tons of hop-up parts and replacement parts online from what I have found.

P.S. I will post up some more pictures later this week. The paint job looks even better now after I let it cure/dry overnight, you can totally see the blue/purple/green in it now. I want to get my new aluminum shocks on there and then get some pics, so stay tuned MT2 fans

eminentguitar

Hey man you have tu get that engine running hotter. No lower then 200 is the best for it. I ran my cvr-x from 240-260 and had tons of fuel through it before I decided it was time to do some crazy mods to it lol. And its still got killer compression.

MattVid

My Feedback: (1)

Yea, it feels like it could go more. It started raining a crap ton today ... and there are like 60MPH winds and thunderstorms tomorrow. I will try leaning it out some more when it gets nice again. I know the LSN is definitely on the rich side (have leaned it out maybe 1/4 turn from factory standard), but the car accelerates quickly. I should try to take a video next time and see what you guys think of the performance ... I honestly don't know what is good and what is bad, haha. But I agree it shouldn't drop below 200, as it will put more wear on the engine from what I have read.

Come on spring! I want to race more

nitro-rob

I have my MT2 together except I need to get the newer style rear shock tower for the newer style body post. I don't know what version of the truck the old posts are from but it wasn't in any of the manuals that can be downloaded on the HPI site (MT1?).

Other than that minor change the truck is good to go except for electronics, but I am likely going to get a DX3 this spring so there is no rush to put anything in there for now.

I am curious about how fast it will go. The box says 73km/h for the G3 truck but its geared shorter than my firestorm that only goes about 35 out of the box but I don't have a comparison of the internal gearing, the FS is 4.1.