Nitro Engine Factory Settings

Alex

New Member
Messages
4
I thought this might be a helpfull thread for everyone who might have lost a manual or did not receive one when they bought a mill second hand.

OS Engines:

18TZ series engines:
High Speed: 2.5 turns out from fully closed
Metering Needle (low speed): flush with carb or ball link body

18CV series engines:
High Speed: 2.5 turns out from fully closed
Metering Needle (low speed): .5 turn in from flush with carb body

21XZ Series engines:
High Speed: Approximately 3 turns open from fully closed
Metering Needle: Rotate until slotted head is flush with carb body

21VG Series engines:
High Speed: 3 turns out from fully closed
Metering needle (low speed): flush with ball link body

21VZ Series:
Depends on the model/version of the engine

21TM Series engines:
High Speed Needle (Needle Valve) 2-1/2 turns out from close.
Low Speed Needle (Metering Needle) 1/2 turn in from flush with carb body.

28XZ engines:
High Speed: 3 turns out from fully closed
Metering Needle (low speed): Rotary: flush with carb body
Slide: flush then 1/2 turn in

30VG engines:
High Speed: 2 3/4 turns out from fully closed
Metering Needle (low speed): flush with ball link body, then 1.5 turns in

Novarossi .21 - .28
HSN: 3.5 turns out from seated
LSN: 5 turns out from seated
IDEL: 0.6mm

LRP Z.28 Spec 3
HSN: 3.75 Turns From Closed
LSN: 3.75 Turns From Closed
IDLE: Gap between 0.5mm and 1.0mm open

Mach 427 (lst2 and muggy)
HSN: 4 turns out from bottom
LSN: 2,5 turns out from bottom
IDEL: .5mm - 1mm

SH .28
HSN: 3 turns out
LSN: 3 turns out
IDLE: 1mm open

Ofna/Hyper .21 engine

Set the master needle IN until stops, then turn OUT 4.5 to 5 turns.

Setting for the black low end needle is OUT 3.5 turns out from flush.

Setting brass head mid range needle, should always be flush to the case

Dynamite Platinum .28 (Mach)

HSN: 3.5 turns out (counterclockwise) from closed.

LSN: 2 turns out (counterclockwise) from closed.

Idle: 1mm gap

STS .21-.30
HSN: 3 turns out from the end
LSN: 4.5 turns out from the end
Idle: 0.5mm open

Force R36
HSN: 3.5 turns from seated
LSN: .5mm out from casing
Idel: 1mm

I have also read that the factory settings in the manual for both the picco .21and .28 are way off.
He is a good starting point that most people have had sucess with.

Picco .21 and .28
HSN: 7 1/2 - 7 3/4 turns out from seated
LSN: 5 1/2 - 5 3/4 turns out from seated
IDEL: 0.5 mm

HPI

Nitro Star S-25
HSN: 4 1/2 Turns From Closed
LSN: 3 Turns From Closed
IDEL: About 2mm

F4.6
HSN: Flush with groove
LSN: Flush with case
IDEL: 1 mm

K4.6
HSN: Flush with groove
LSN: Flush with case
IDEL: 1 mm

K5.9
HSN: Flush with groove
LSN: Flush with case
IDEL: 1 mm

HPI also recommends not to adjust the mid range needle.

For The traxxas lovers out there :p

TRX 2.5 & 3.3
HSN - 4 turns out
LSN - flush with valve or 1.5-1.75 turns out
IDLE 0.70-1mm open.

I know there are engines that I missed so feel free to add at will.
I have a savage 25 I know their discontinued but what are the factory settings for it
 

Jam Racing 1

NPTB MONITOR & Master of the known Universe
HPISF Staff
Messages
4,650
Savage 25 is at the bottom there all by itself....

Nitro Star S-25
HSN: 4 1/2 Turns From Closed
LSN: 3 Turns From Closed
IDEL: About 2mm
 

Alex

New Member
Messages
4
Savage 25 is at the bottom there all by itself....

Nitro Star S-25
HSN: 4 1/2 Turns From Closed
LSN: 3 Turns From Closed
IDEL: About 2mm
Ok now my rc won't start I think it's out of tune should I set it to factory and try then?
 

joegibbstruck

Well-Known Member
Messages
238
Location
humble, tx

And if it has a msn it would be on the opposite side of the lsn, and the side of the aluminum housing.....it's typically bad practice to adjust the MSN.
 

rikkidy

Well-Known Member
Messages
158
Location
Mission B.C.
I thought this might be a helpfull thread for everyone who might have lost a manual or did not receive one when they bought a mill second hand.

OS Engines:

18TZ series engines:
High Speed: 2.5 turns out from fully closed
Metering Needle (low speed): flush with carb or ball link body

18CV series engines:
High Speed: 2.5 turns out from fully closed
Metering Needle (low speed): .5 turn in from flush with carb body

21XZ Series engines:
High Speed: Approximately 3 turns open from fully closed
Metering Needle: Rotate until slotted head is flush with carb body

21VG Series engines:
High Speed: 3 turns out from fully closed
Metering needle (low speed): flush with ball link body

21VZ Series:
Depends on the model/version of the engine

21TM Series engines:
High Speed Needle (Needle Valve) 2-1/2 turns out from close.
Low Speed Needle (Metering Needle) 1/2 turn in from flush with carb body.

28XZ engines:
High Speed: 3 turns out from fully closed
Metering Needle (low speed): Rotary: flush with carb body
Slide: flush then 1/2 turn in

30VG engines:
High Speed: 2 3/4 turns out from fully closed
Metering Needle (low speed): flush with ball link body, then 1.5 turns in

Novarossi .21 - .28
HSN: 3.5 turns out from seated
LSN: 5 turns out from seated
IDEL: 0.6mm

LRP Z.28 Spec 3
HSN: 3.75 Turns From Closed
LSN: 3.75 Turns From Closed
IDLE: Gap between 0.5mm and 1.0mm open

Mach 427 (lst2 and muggy)
HSN: 4 turns out from bottom
LSN: 2,5 turns out from bottom
IDEL: .5mm - 1mm

SH .28
HSN: 3 turns out
LSN: 3 turns out
IDLE: 1mm open

Ofna/Hyper .21 engine

Set the master needle IN until stops, then turn OUT 4.5 to 5 turns.

Setting for the black low end needle is OUT 3.5 turns out from flush.

Setting brass head mid range needle, should always be flush to the case

Dynamite Platinum .28 (Mach)

HSN: 3.5 turns out (counterclockwise) from closed.

LSN: 2 turns out (counterclockwise) from closed.

Idle: 1mm gap

STS .21-.30
HSN: 3 turns out from the end
LSN: 4.5 turns out from the end
Idle: 0.5mm open

Force R36
HSN: 3.5 turns from seated
LSN: .5mm out from casing
Idel: 1mm

I have also read that the factory settings in the manual for both the picco .21and .28 are way off.
He is a good starting point that most people have had sucess with.

Picco .21 and .28
HSN: 7 1/2 - 7 3/4 turns out from seated
LSN: 5 1/2 - 5 3/4 turns out from seated
IDEL: 0.5 mm

HPI

Nitro Star S-25
HSN: 4 1/2 Turns From Closed
LSN: 3 Turns From Closed
IDEL: About 2mm

F4.6
HSN: Flush with groove
LSN: Flush with case
IDEL: 1 mm

K4.6
HSN: Flush with groove
LSN: Flush with case
IDEL: 1 mm

K5.9
HSN: Flush with groove
LSN: Flush with case
IDEL: 1 mm

HPI also recommends not to adjust the mid range needle.

For The traxxas lovers out there :p

TRX 2.5 & 3.3
HSN - 4 turns out
LSN - flush with valve or 1.5-1.75 turns out
IDLE 0.70-1mm open.

I know there are engines that I missed so feel free to add at will.
 

pantera-x

Member
Messages
47
i have the 4.1 engine and it wheelies but not all the time" depends on what tires I'm running and what surface I'm running on",the 4.1 is actually a pretty good engine in my opinion....

P.S.. GREAT THREAD KEVIN!!!! REPS SENT
I have the savage 4.1 and it wheelies on command.i run a 17t cb and 49t spur
 

crazydriver

Member
Messages
11
Location
south Mississippi
On the f4.6 HSN which groove should the needle be flush with. My son was gifted a slightly used savage x big block and the carb is out of whack. I have adjusted the idle screw to 1mm and have the LSN flush with it's housing on the end of the barrel. Not sure exactly where to set the HSN though. Also noticed that when the throttle servo is at neutral the barrel does not return to the idle stop unless i apply the break. Once I do that it will stay in place. I'm thinking perhaps there may be some dirt gumming up the works due to the fact that the air cleaner boot is loose and did not have a zip tie securing it. the whole kit needs a good clean, lots of dirt, grass and some grime. We are having trouble getting it to start. sometimes she'll bust right off and run a bit others we will have to play with the throttle a bit before she will come to life. Also have a good bit of unburnt oil coming out of the exhaust. Anyone with some insight would become my new best friend, my son is anxious to hit the gravel pits with this truck.
 

timatworksg

Well-Known Member
Messages
149
Location
Singapore
+1 on the engine tear down and clean. Did that when I got a used Savage that was never cleaned since day 1! The sealing works wonders to. With a good seal...you eliminate one problem area for troubleshooting so less headaches...lol!
When you re-build, make sure the throttle arm to the carb is not angled or tilted and the carb ball pin is parallel with the arm. Also the return spring is pulling level and not twisting your carb gap when closing. If the throttle arm isn't level and parallel, your carb can stick sometimes or have an un-smooth return. Loosening the small lock nut just below the ball pin will adjust the position.
 

crazydriver

Member
Messages
11
Location
south Mississippi
Thanks for the speedy replies, I was thinking the same on the complete tear down clean and seal. I have viewed several threads and vids on the tear down and seal. The only thing I'm not sure of is the factory setting of the HSN. I am seeing it should be
flush with groove. The only ggroove I see would put the needle fully closed. When I get home I will take some pics to share to show what I'm working with before I start pulling the truck down.
 

Jam Racing 1

NPTB MONITOR & Master of the known Universe
HPISF Staff
Messages
4,650
HSN opening is going to vary some , but commonly about 2 1/2 turns open if the engine is fully broken in and running well... even the LSN is going to vary, there is no magic opening where they are supposed to be....
 

rikkidy

Well-Known Member
Messages
158
Location
Mission B.C.
The problem I have is the plastic collar on the HSN is sloppy and I think it moves up and down so I never know if I am close.
Thanx Jam I will give the 2.5 turns a try.
 

WoodiE

Kind of good admin
HPISF Staff
Messages
1,468
Location
Kentucky
If there are additional nitro engines you'd like added to the thread, be sure to let us know!
 

Jam Racing 1

NPTB MONITOR & Master of the known Universe
HPISF Staff
Messages
4,650
What :ercm: is in your Mammoth, I have an XTM MMT which is very similar to the mammoth truck. if it is the XTM 24.7 or the SH .28 then it is in the list I linked above..
 

wew5575

Member
Messages
6
These are my first hobby grade rc's. Other than a 1/18 ruckus for my 8th old.... Have to say that is one tough little truck tho.
 

Jam Racing 1

NPTB MONITOR & Master of the known Universe
HPISF Staff
Messages
4,650
hard to tell with your pics..... maybe a couple close ups of it so we can see what :ercm:....

as for being your first hobby grades I would only say going nitro with the first ones and used ones at that I can only hope you have some mechanical background to help you through the hard spots......
 

wew5575

Member
Messages
6
I do have a friend that has been into nitro for years. However he is busy with sweetest day this weekend so no luck getting help from him.....lol
 
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