1Likes"the tuning bible"
07-27-2009, 01:36 AM
#91
No, actually it's a bit rich....
Lean it a bit, and lower your idle....
Because of the rich LSN, you had to set a high idle setting, after a high speed pass, the engine is fully cleaned out, and then running a high idle until it loads up again....
Lean it a bit, and lower your idle....
Because of the rich LSN, you had to set a high idle setting, after a high speed pass, the engine is fully cleaned out, and then running a high idle until it loads up again....
07-27-2009, 07:24 PM
#92
Lean it out a touch and re-set your idle!
07-29-2009, 06:22 PM
#93
Tech Regular
iTrader: (19)
In this method it mentions that if you blip the throttle and the engine idles high for a few seconds then drops (which my engine does) then you should lean out the LSN until it idles high for 20 seconds, then change the idle screw appropriately. I'm going to assume screwing in the idle screw opens the carb more (which my carb does do from my observation) and hence if i want to decrease idle i should close the carb ie undo the screw. Let me know if this is right philosophy please
Also, after changing the idle screw via this process... do you keep the LSN as is? or do you readjust the LSN depending on smoke/performance again, now that the idle is set properly...
I'm a total novice to RC so yeah... please help out a young'un
Cheers
Also, after changing the idle screw via this process... do you keep the LSN as is? or do you readjust the LSN depending on smoke/performance again, now that the idle is set properly...
I'm a total novice to RC so yeah... please help out a young'un
Cheers
07-31-2009, 08:08 AM
#94
Tech Apprentice
Hi
Run the engine for a tank of feul to get everything hot. refuel the tanks and do a high speed pass come back in and check the lsn by listening to the idle if it idles high and then drops you have a rich botoom end and should lean the LSN by 1 hour turning it in (Clockwise).
Do another full speed pass bring the car in and listen to the idle again you will notice that it still high idles but not for a long. Keep doing Full speed passes and continue to lean the LSN until the idle stays high.
now with the engine still running turn the idle screw to the left (Counter Clockwise) you will notice the idle speed drops. Set it so the idle is nice and smooth and sounds constant the clutch should not be engaging.
once you have done this the LSN and idle is tuned and you dont need to touch them.
last of all check the HSN and tune accordingly beause your rich bottom end could be hiding a lean top end
Hope that helps
Ben
Run the engine for a tank of feul to get everything hot. refuel the tanks and do a high speed pass come back in and check the lsn by listening to the idle if it idles high and then drops you have a rich botoom end and should lean the LSN by 1 hour turning it in (Clockwise).
Do another full speed pass bring the car in and listen to the idle again you will notice that it still high idles but not for a long. Keep doing Full speed passes and continue to lean the LSN until the idle stays high.
now with the engine still running turn the idle screw to the left (Counter Clockwise) you will notice the idle speed drops. Set it so the idle is nice and smooth and sounds constant the clutch should not be engaging.
once you have done this the LSN and idle is tuned and you dont need to touch them.
last of all check the HSN and tune accordingly beause your rich bottom end could be hiding a lean top end
Hope that helps
Ben
07-31-2009, 09:10 AM
#95
so the ideal case is that after a high speed pass when you bring the car in, the engine should drop to normal idle immediately?
07-31-2009, 02:31 PM
#96
Tech Apprentice
yes the idle will always stay the same no rise no drop
08-07-2009, 11:32 PM
#98
just bought a rossi .21 and broke it in.. i'm having trouble understanding the damn thing (i can't find the lsn)... let alone running it.. anyone know where i could find some pictures or videos?
08-08-2009, 12:08 AM
#99
Rossi or Novarossi? Both have extensive information about the engines on their websites.In both engines, the low-speed needle is in the end of the slide valve, nearest where the throttle linkage attaches.
Last edited by SteveP; 08-08-2009 at 12:24 AM.
08-08-2009, 12:20 AM
#100
08-12-2009, 12:25 AM
#101
08-21-2009, 05:19 PM
#102
Tech Addict
You have it mostly correct. It's not really wearing because it's thin. Both coatings will wear, but the nickel wears half as much as the chrome. Lets say for example that the NSC sleeve wears 3µm, then the hard chrome would wear about 6µm under the same conditions. The piston however, is where there's a big difference. In an engine with a hard chrome sleeve, this piston may wear 20µm, but the same piston under the same conditions with a NSC sleeve will probably wear 60-70µm. So, it's easy to see why the performance degrades more quickly in engines with NSC sleeves - it kills the piston.
If the NSC coating is applied via chemical process instead of electrochemical, it can be as thin as .3µm, whereas chrome starts about 2 to 3 times thicker, and gets multiple passes. So, the opportunity for the coating to wear through a NSC sleeve is greater if it's not applied thick enough. but the RATE of wear is still much lower when all other factors remain the same.
If the NSC coating is applied via chemical process instead of electrochemical, it can be as thin as .3µm, whereas chrome starts about 2 to 3 times thicker, and gets multiple passes. So, the opportunity for the coating to wear through a NSC sleeve is greater if it's not applied thick enough. but the RATE of wear is still much lower when all other factors remain the same.
09-04-2009, 03:53 AM
#103
Tech Apprentice
PLEASE HELP ME :-)
I have excatly the same "issue" on my engien (O.S. V-Spec blue head).
Two things you must know before I describe the issue:
When I come in to fuel, I do this only with a 1/4 throttle because it is quite difficult to get in our pit lane. And the pit lane is really narrow.
That means the engine has normal idle and it is close to stop.
But when I stop the car at the track after a high speed pass it has a higher idle.
If I blip the throttle it returns to normal idle.
If I do not blip my throttle it takes 5s to 10s to go down to normal idle.
I understand that you all recommend to lean the LSN as M7H has done:
"No, actually it's a bit rich....
Lean it a bit, and lower your idle....
Because of the rich LSN, you had to set a high idle setting, after a high speed pass, the engine is fully cleaned out, and then running a high idle until it loads up again.."
Lean it a bit, and lower your idle....
Because of the rich LSN, you had to set a high idle setting, after a high speed pass, the engine is fully cleaned out, and then running a high idle until it loads up again.."
And I lowered the idle.
It feels perfect after a high speed pass.
But if I blip the throttle it lowers the idle and it's really close to stop or it stops.
Same when I come in to fuel with 1/4 throttle the idle is really low and after 1 to 5 sec it stops.
Some of my colleagues told me I am to slow I shall race a bit faster this solves my issues :-)
but I hope you can recommend something better.
Thanks a lot
racer_hh
09-04-2009, 04:38 AM
#104
Hi.
Try a hotter plug and retune. What plug do you use now, and how much nitro?
Have you added or removed shims in the top?
Cheers
Try a hotter plug and retune. What plug do you use now, and how much nitro?
Have you added or removed shims in the top?
Cheers
09-04-2009, 05:09 AM
#105
very good suggestion...
Well actually, what you just described is quite normal and as suggested by Lille-bror, try to put in a hotter plug (go from 7 to 6, or from 6 to 5)
When driving 1/4 throttle through the narrow pitlane, your engine will load-up...
Maybe you can also just set idle a bit higher...