I recently got an MTX-3 with the stock engine (MR12). Just found out that the piston, liner and conrod are not being imported anymore. Can I use the ones from the newer version novarrossi engines? Any help would be appreciated.

rs4lola: sorry for not getting back to you on this before, busy buying a house...YES, change that rod. If you don't do it soon, do it before you get to a gallon. I had almost 2 gallons through the motor before I changed mine. As for the choise of pipe, toss the RD pipe, go get yourself an Ofna X-12 pipe, and run the restrictor in the carb, it won't hurt. The restirctor doesn't effect the motor that much, you will be breaking loose the rear if you don't, trust me. Oh, when you do switch to the x12 pipe, it is going to be A WHOLE LOT MORE POWERFUL.....If you know Ravi from Fast and the Furious R/C, he can vouch for the motor, he has been watching it, but like I said, I need more track time.(working on that) I just took an old rossi pixy black and modded the heck out of it, and it isn't even close to the RR, but this rossi is an experiment. I still have some work to do on the crank. Although, I havn't even touched the RR, it doesn't need it.

Anyone know some great pipes to run with an MT12? I run a THS pipe at the moment, but I'm guessing it can run much better than this.

Mugen pipe, works very well, and the STS pipe too.

EFRA 2601 pipe is the best

Who makes that EFRA 2601?

Novarossi.....

But not only Novarossi sell this pipe.......

here are the brands which are selling the pipe:

NOVAROSSI, REX, TOP, JP RACING.....

The same pipe is sold as EFRA 2602 by NovaMAX

and also RB Concept sells the pipe as EFRA 2604 (not sure if the number is right, but the pipe is identical anyway)....

you'll find slightly differences on the pipe stinger length between these brands.....

Cool. Are these one piece pipes or I'll need a RE manifold? Also what's a good plug for the MT12? I run an RB #6, but don't recall any performance difference, because in the past I ran blue thunder with the stock black #4 plug.

yes.....

it's sold as one piece kit........and also sold as spare parts separately......

here in Brazil Novarossi #6 plugs (same as RB) were my favourites when I used to run MT12 engines......

RCFoolz
1) How much approx is a con-rod for the RR12L3??
2) Does the Ofna X-12 come in a right side version for the rs4-3ss or Tamiya TG10 Mk 2??
This is my first rear exhaust engine and I feel a liitle nervous trying to replace the con rod my self. I will probably get someone from the hobby store to do it. The engine is barely broken in with about 10-11 tanks thru it which is at least half a gallon. I will take your advice as I want to run this engine competetively all thru spring, summer and fall. Yeah the back end does move out a little if you gun it from start. And that was with a tall first gear and 1/8 foams. I have since shortened the gears and can't wait to run it soon. I am also running 30% with no shims. I can go at least 10 minutes, idles absolutely rock solid, no flame outs and even though it smokes a little on acceleration, hardly any oil on the exhaust or body!!! How should I tune this properly?? I have barely turned the high needle with the low needle turned just enough so the engine does not stall and the clutch is dis-engaged. Ballistic acceleration with this setup and that was with a 3-shoe clutch. I have since got a centax and I assume I should get even better acceleration...

18$

Sounds like you are running TOO LEAN if you are getting 10min from a tank. and you should be getting some oil on the side of the car too, at least a trace. I've gotten good performance from mine, but I'm getting about 6 min. The rod is part number 07601(novarossi) it is about $35 and not hard to change.

RCFoolz
If I richen it anymore the engine dies when I give it gas. Does this mean it is too rich?? I have tried richening the low speed needle as long as i can still idle without engaging the clutch. I have turned the low end half a turn and the high sped needle 1/8 of a turn from stock. I am assuming I have barely touched the needles. The temp is between 220-240 and I have NO problem restarting once the engine is upto temp. I had to use a heat gun for 7-8 tanks just to get this thing to turn over!!!

Actually I'm thinking of selling the MT12. $100 bux and $9 for shipping and insurance. Figured I'd get myself a much faster engine since it seems quite slow in these large parking lots bashing with my friends Mugen 8th onroad. For the price the Sirio Evo II seems good and offers lots of power, but the NS12 is tempting.

rs4lola: If your temps are in that range, you should be fine. what type of fuel are you running, nitro/oil content. If you are running a low oil content, you won't have that much of a trace.