1Likes"the tuning bible"
01-19-2010, 12:05 AM
#166
NOVAROSSI ENGINE TUNING
hsn is the control valve, set the control valve first when final race tuning . after doing so go to the lsn and lean until the engine keeps a consistent idle but does not ting when idling , that is caused from lack of fuel on lsn . lower the idle until it is as low as you can get it and it will maintain a good safe idle during on track decel and on the bench for at the least 20 sec.
after you do the low end you will usually have to richen the hsn about 1-2 hours
there will be a few things that will need to be tweaked slightly but that will get you in the ball park .
OTHER ENGINES TUNE DIFFERENTLY !!!!
from page 1
hsn is the control valve, set the control valve first when final race tuning . after doing so go to the lsn and lean until the engine keeps a consistent idle but does not ting when idling , that is caused from lack of fuel on lsn . lower the idle until it is as low as you can get it and it will maintain a good safe idle during on track decel and on the bench for at the least 20 sec.
after you do the low end you will usually have to richen the hsn about 1-2 hours
there will be a few things that will need to be tweaked slightly but that will get you in the ball park .
OTHER ENGINES TUNE DIFFERENTLY !!!!
from page 1
The way you descript it, sounds similar to tuning any engine... or does the LSN influence on the HSN in a Novarossi carburator?
Thanks
01-20-2010, 09:47 AM
#168
01-23-2010, 04:04 PM
#170
I just wanted to thank you all. By reading this thread, I was able to make my buddies Losi 8ight scream!! I never really understood tuning but then I read this and shazam!!! Tuning was never any clearer.
02-15-2010, 04:43 PM
#171
Anyone have any suggestions for the following tuning issue I'm having with a nova +4:
After clearing the carb with a full throttle pull, engine comes down to idle. 1 second later it goes to a higher overly idle for 2 seconds, than back down to a normal idle for 20 to 30 seconds.
When I richen the LSN from this point, it goes to a high idle and then to a rich low idle after about 6 or so seconds and dies sooner.
After clearing the carb with a full throttle pull, engine comes down to idle. 1 second later it goes to a higher overly idle for 2 seconds, than back down to a normal idle for 20 to 30 seconds.
When I richen the LSN from this point, it goes to a high idle and then to a rich low idle after about 6 or so seconds and dies sooner.
02-15-2010, 05:04 PM
#172
02-16-2010, 10:18 AM
#174
Anyone have any suggestions for the following tuning issue I'm having with a nova +4:
After clearing the carb with a full throttle pull, engine comes down to idle. 1 second later it goes to a higher overly idle for 2 seconds, than back down to a normal idle for 20 to 30 seconds.
When I richen the LSN from this point, it goes to a high idle and then to a rich low idle after about 6 or so seconds and dies sooner.
After clearing the carb with a full throttle pull, engine comes down to idle. 1 second later it goes to a higher overly idle for 2 seconds, than back down to a normal idle for 20 to 30 seconds.
When I richen the LSN from this point, it goes to a high idle and then to a rich low idle after about 6 or so seconds and dies sooner.
02-24-2010, 09:51 PM
#175
Tech Regular
iTrader: (9)
Anyone have any suggestions for the following tuning issue I'm having with a nova +4:
After clearing the carb with a full throttle pull, engine comes down to idle. 1 second later it goes to a higher overly idle for 2 seconds, than back down to a normal idle for 20 to 30 seconds.
When I richen the LSN from this point, it goes to a high idle and then to a rich low idle after about 6 or so seconds and dies sooner.
After clearing the carb with a full throttle pull, engine comes down to idle. 1 second later it goes to a higher overly idle for 2 seconds, than back down to a normal idle for 20 to 30 seconds.
When I richen the LSN from this point, it goes to a high idle and then to a rich low idle after about 6 or so seconds and dies sooner.
anyone know im havin a similar prob whit an os tz
02-28-2010, 03:44 AM
#176
If the idle climbs up in RPM and stays there, it typically tells you that the low-speed mixture is too lean. If it idles high after cleaning out the engine, then gradually returns to a normal idle, then the main needle is a little lean. If it does anything beyond that, then it's time to check the fuel system. When the idle fluctuates like you've described, then there's usually a pressure or vacuum leak somewhere. Check that all your fuel lines are properly attached and that there's no cracks or cuts in them. You also want to be sure the fuel filler cap is completely closed and sealed. If the pressure line from the exhaust or the filler cap aren't sealed properly, then the amount of fuel going into the engine will fluctuate. A loss of pressure in the fuel system usually makes the mixture lean, which is accompanied by an increase in RPM.
Less typical but still a possibility is a vacuum leak in the carburetor or around its base. If this isn't sealed well, you can experience the same symptoms. Start by checking all the obvious stuff like making sure the the carb fastener is tight and that the carb is fully seated in the block. If that's OK, then be sure that there's no tears in the bellows seal on the slide valve, and that the main needle assembly isn't loose. You can go through the carb and seal everything with a little silicone sealer, but only do that if you're comfortable taking the carb apart. The only thing I caution here is to use TRACE amounts of silicone sealer. I've seen many "seal" jobs that end up causing other problems because WAY too much sealer is used. Only a very small amount of sealer is needed.
A third possibility is that the carb simply isn't closing all the way when you let off the throttle. If the carb is dirty and you're not using a carb return spring, it might simply be a matter of the carb not closing down complete until a few seconds after letting off the throttle. Vibration will usually cause the throttle to eventually close, so just be sure you haven't let the maintenance go so far that the slide valve is simply unable to move quickly and freely.
Less typical but still a possibility is a vacuum leak in the carburetor or around its base. If this isn't sealed well, you can experience the same symptoms. Start by checking all the obvious stuff like making sure the the carb fastener is tight and that the carb is fully seated in the block. If that's OK, then be sure that there's no tears in the bellows seal on the slide valve, and that the main needle assembly isn't loose. You can go through the carb and seal everything with a little silicone sealer, but only do that if you're comfortable taking the carb apart. The only thing I caution here is to use TRACE amounts of silicone sealer. I've seen many "seal" jobs that end up causing other problems because WAY too much sealer is used. Only a very small amount of sealer is needed.
A third possibility is that the carb simply isn't closing all the way when you let off the throttle. If the carb is dirty and you're not using a carb return spring, it might simply be a matter of the carb not closing down complete until a few seconds after letting off the throttle. Vibration will usually cause the throttle to eventually close, so just be sure you haven't let the maintenance go so far that the slide valve is simply unable to move quickly and freely.
02-28-2010, 04:50 PM
#178
i have a ninja. I will be going from 30% to 20% also from a p3 to a p4 plug. Should i take out the copper shim and just leave the silver one?
btw, it is almost impossible to get this darn thing up to temp no matter how much i lean it. I have just about fried one P/S set and i have another i am putting in that has been broke in.
My old one would run a 160 degrees at best. It is now fried because of being to lean.
Weird. And no the temp gun is not broken.
anyway, just some info on the shim. My tuning is not all that great.
btw, it is almost impossible to get this darn thing up to temp no matter how much i lean it. I have just about fried one P/S set and i have another i am putting in that has been broke in.
My old one would run a 160 degrees at best. It is now fried because of being to lean.
Weird. And no the temp gun is not broken.
anyway, just some info on the shim. My tuning is not all that great.
02-28-2010, 06:23 PM
#179
This is why we say, NEVER tune to the temp gauge. Tune it for performance and CHECK the temp. 
Leave the shimming alone for now. Reducing head clearance requires that you be more skilled at engine tuning, or you may cause detonation, which is going to smoke your engine (as in kill it). I only recommend adjusting head clearance for people that can get the tune right 10 out of 10 times.
Leave the shimming alone for now. Reducing head clearance requires that you be more skilled at engine tuning, or you may cause detonation, which is going to smoke your engine (as in kill it). I only recommend adjusting head clearance for people that can get the tune right 10 out of 10 times.
02-28-2010, 06:33 PM
#180
This is why we say, NEVER tune to the temp gauge. Tune it for performance and CHECK the temp.
Leave the shimming alone for now. Reducing head clearance requires that you be more skilled at engine tuning, or you may cause detonation, which is going to smoke your engine (as in kill it). I only recommend adjusting head clearance for people that can get the tune right 10 out of 10 times.
Leave the shimming alone for now. Reducing head clearance requires that you be more skilled at engine tuning, or you may cause detonation, which is going to smoke your engine (as in kill it). I only recommend adjusting head clearance for people that can get the tune right 10 out of 10 times.