Sounds a bit like you need a slightly bigger idle gap, then adjust accordingly.. From what you describe after doing that, maybe you need to richen up the HSN a tad?...

I would check a couple of things.

How old your fuel is and how well has it been sealed.

eventhough it's a new engine double check the front bearing. They can still leak. Personally if I had experienced what your going through I would change the bearing regardless.

thanks man. I reset my needles to factory specifications in order to try and get it tuned again. I may just forget about trying to get this perfect idle, because I can get it running really well on both the low and high end, just with an idle that last no longer then a few second. Might just bump up the idle screw a bit and say to hell with it lol.

my fuel is indeed fresh. Or I assume it was. It was from Amain a few weeks ago and was sealed perfectly, and I store all my stuff indoors. It’s funny you mention about the bearing, because to me it seems like it may be an air leak issue. My fuel tank is the old school ones with a primer button on top, it is a new tank with new lines but you may be on to something with the bearings. I didn’t think about that because I don’t race, the engine is literally brand new, and I think I have the good novarossi bearing(blue seal). Unfortunately I don’t really have the tools or workspace to change bearings, but I guess I could send it out and get it done. I really just wonder if it’s the poor stock tank though

Did that engine have the long or short LSN
with 20% id recommend a 5 plug, with any tuning issues check the fueling system first IMO.
get the engine nice and warm put the truck up on blocks, slowly pull the throttle open to fully open and listen to it and watch the smoke and take note. once you get up to high rpms close the carb and see how it reacts. if you make any changes give a short burst of full throttle to clean out the engine and do the slow pull again. once you get the engine sounding good and consistent through the whole pull move to2-4 second full throttle bursts followed by full brake for 2-4s and full throttle for 2-4s.once you get it set so it doesn't go lean during these bursts your going to be 95% in the ballpark to a race tune.
once your engine is this close any slop in the linkage or your throttle return spring not holding the carb fully closed is going to make the idle seem funky

Not looking to start an argument, but IMPO these things are very rarely an air leak or bearing problem.. Fuel tank, maybe.. But very unlikely with a new one.. I think it just needs more messing with. Maybe try a hotter(or just another fresh) plug as suggested. But as you said, if you can get the low and high good, then just live with blipping it as necessary.. But then I am used to that with most of my big block engines.. A Nova I would expect to idle more nicely though. (my LRP ZR.30X idles perfectly though..) Basically, just keep at it...

Ive had plenty of tanks that wouldnt seal properly out of the package thats why the lids are adjustable.

If you've had "plenty" of faulty brand new tanks, then you're running brands I never have, and wouldn't if I had to expect faulty tanks...

whatever i was just giving some advice that almost all tuning issues come down to the tank seal and poorly set up linkage. I then gave the method the guys that get paid to do this do to get an engine 95% to a race tune. If you want to get into an experience and who i race with pissing match im not into it.

Hey guys I have good news. So I reset my low and high speed needle to factory novarossi specifications. I changed the glow plug to a basically new cto6(only one I had) that had maybe a tank ran through it total, it was perfect. I opened up my new gallon of byrons 30/11 and ran that instead. Leaned the high speed maybe an 1/8 of a turn from factory, the low speed a half turn or so, bumped up the idle maybe 1/12 of a turn. And now it’s running great! Thanks to both herrsavage and haulinbass for your inputs. I think the higher nitro with the ct06 plug really helped, as did retuning from factory. Engine ran crisp( could probably be leaned even more, and idled pretty dang good. Even at the very end of the huge Losi LST tank, no lean bogging whatsoever. Super happy guys

I'm not interested in pissing matches either. I have no doubt that you have 100x more nitro experience than I do. I am however pretty confident when I say that over all the years I've been into it, people always say "it's an airleak", or "change the bearing", and that is almost never the case. I used to seal engine carbs and backplates with silicon goup back 12-14 years ago, and I don't think it did jack. Nor does changing bearings on new engines, or rods after a gallon, or pre-heating beyond break-in for that matter. Now you race guys who care more about getting 12 seconds more run time than actually having fun...( )* might do things differently, but by and large if a nitro engine is not running right, %90 of the time it's the needles..

I recently ran all my cars this year, with 5-year old fuel ("Fuel is bad" is another fairy tale/myth diagnosis IMO...), and they all ran great. Surprisingly so, given that in forums all anybody ever says is you have to change 12 different things if you let it sit a few months...

And I still think if you are expecting tanks to be faulty then something is wrong. (Rare...) exception to the rule? Maybe... But the rule, to the point that you should expect it? No.. Not in my opinion. Not unless you are running the cheapest of the cheap brands, which I'm sure you are not.

I seriously doubt it is an airleak or bearing issue either....

* I know racing puts more strain on things than most other types of use...


ps - Losi215, way back when I had a Nova 528XR, and I absolutely hated it. At the time I ran Sidewinder %25, which ran great in all my other - non-Italian - engines(LRPs, Machs, Axials, etc..) I could never get that dumb Nova to run right though.. I ended up selling it, nervous that something was wrong with it, but the guy contacted me and said thanks, it ran great... He was using a different fuel. After SW fuel was no longer available, I changed to Tornado %25, which I think has slightly less oil, and all my engines ran great with it, including various racing 21s, including Novarossis and RBs.., but also my MT non-Italian engines... So there could be something to a fuel with too much oil in it (I don't know, more than %12 or something I guess...) But even then I'd be a bit skeptical and still think you just need to fiddle with the needles more, and/or maybe just get some more fuel through it, in case part of what's going on is that it's just being bitchy during break-in....

herrsavage, I completely agree with the fuel. I remember a lot of the fuels(especially back in the day)had a ton of oil, 16-18 percent if I recall correctly, and that was way too much. I think 10-12 percent is perfect for bashing, less is preferable with racing I guess but I am absolutely not a racer so I’ve never really dipped into the single digit percentages of oil. Haulinbass wanted me to put in a hotter plug which I don’t have on hand, so I thought to myself since I’m running a medium novarossi cto6 plug,I could probably bump up the nitro percentage and cut down on the oil. The engine definitely ran much better on the byrons 30/11 percent oil blend, I didn’t have to lean the needles as much to get acceptable performance, and my idle was more stable. I also agree with the break in process, sometimes I forget that it does take a good bit of fuel to get these novas broken in fully, it’s not like you run 5-6 tanks and the break in process is over. I’m at about 3 quarts, and when my engine is room temperature with the plug in, it is very difficult to turn the flywheel over by hand. Looking forward to running again, ran 4 tanks the last two days and nothing broke, clicked, binded, or stopped working and I’m super Happy about all of it. Thanks again guys

Check and or change your slipper clutch, 2 speed clutch, and engine clutch

hey thanks for the info brother. I actually have all new spurs gears, low and high speed shift hubs, new tko heavy duty clutchbell bearings, newish losi aluminum clutch shoes and springs. And I got the engine tuned pretty well last time I was out. Changed my fuel and glow plug, retuned from factory settings and I’m good to go. Probably would be a good idea to change my 2 speed clutch and slipper setup, mine do look to be in good shape though. Thanks again for the input

Glad to help. Changing the 2 speed clutch helped mine a lot because it was hanging up going back to first gear and idle wouldn't drop. I had to blip the throttle to get it back down quicker.