So i recently just got a matrix rtr and it came with the new needles for the carburetor. All that came with the needles is a little 2 inch piece of paper saying change out the needles with the ones that are currently in the engine now. Now i had no problem getting the low speed needle in but the the mid needle just does not fit. I compared it to the one that was in the carb when i got it and i can see why it wouldnt fit. The end of the replacement needle is a little bit wider so it wont fit into the housing of the carb correctly. One thing that worries me is that people may not realize this and try to force it in and then theyll get tons of little metal shavings in the engine. I dont know if i just got a defective set of needles or what but i was wondering if anyone else had problem with this?


P.S. the engine runs fine with the stock needles but it does tend to run pretty hot even though its still relatively rich. I heard these needles would help correct that. Is that what these needle are for?

yes, because they needles are leaking air which means the engine is leaning out without any needle control

have the matrix also and it would die at about 1/2 tank nothing worked I contacted cen they sent me a new tank and the needles for the engine now it wouldnt run longer then 15 seconds etc. So I pulled the engine and sent it in to cen as per thier request they ended up sending me a new engine that runs great. Mind you I been in the rc hobby planes helis etc for 40+ years and when a company does what they did it makes me happy and I will buy from them again.

Yeah guys... when I get faulty engine back... (cuz when i get sick of 3rd speed phone calls i like to wrench)most times I will even break it in and tune it for you-
hell I even fanged out a rebuilt on-road motor and that thing screams... don't hesistate to ship in stuff that you tink is running funny... our customer satisfaction is the best in the biz!!!
Thanks for chossing CEN products,
Notch

I also switched out my needles, but when I did, I tore the o-ring on the msn. don't know why? anyway I haven't been able to try it out here in Canada, too cold, but am anxious to. Also the ball head on the carb where the servo arm connects, how do you get that off, I tried and stripped it, I didn't even turn it hard.

ps, CEN does have great service, and I am sticking with them.

you need to grease the orings or lube em or they will tear real easily during insertion
the ball thing comes off with an .050 wrench if im not mistaken

If you are having further problems contact CEN
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