• Welcome to RCTalk! 🚀

    Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!

    • Friendly & passionate RC enthusiasts
    • RC tips & troubleshooting
    • Buy, sell & trade RC gear
    • Share builds & upgrades

tuning troubles.

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

swnichols

RC Newbie
Messages
4
Reaction score
0
Points
0
RC Driving Style
  1. Bashing
i just got a savage 25. with a 4.6 engin. my first one. its used. for some reason it wont shift. how do i adjust it? also what are the factory settings on the high and low speed needles on the engin. it keeps stalling. I'm new to this and realy engoy it.
 
First, start with a copy of the manual. It sounds like you didn't get one with the truck.

http://rcdocuments.com/HPI_Savage_25_Manual.pdf

The manual shows how to adjust the two speed, adjust the slipper clutch, and more.

The factory settings on the S-25 engine are 4.5 turns from seated on the high needle and 3 turns from seated on the low. As you probably surmised, there's no mid-range needle like the older .21 big-block in the original Savage...

As for the shifting issue, it either needs to be adjusted, or tuned better (mine has to be tuned fairly well for it to shift) or the clutch/spur combo is so off it can't get enough rpm into the trans to shift it. Most likely it needs a better tune.

If the engine has good compression but a lot of nitro through it there's probably no need to go back to the factory settings. They are usually way rich for a broken in engine...

When does it stall? When accelerating? When braking? Will it hold an idle?

HTH...
Mark
 
it idles high. and mostly stalls when i stop or slow down but it will start right back up. if i turn the idle down it stalls. it has good compression. i got it used from a friend and he got it from someone down in lousiana or somewhere in that area. i live in maine. would that make any differance. thanks for the info. I'm fairly new at this.
 
Sounds like your a little lean. Louisiana is way more humid, which requires a leaner tune. But the no shifting would indicate an overly rich tune. Does the truck jump off of the line, then kinda bog down, while smoking excessively? If so, the hsn needs leaned, while the lsn will need richened a hair. A lean lsn would cause a high idle and stalling. A rich hsn would cause bogging(loading up) and no shifting, due to the engine not reaching high rpms. I would richen the lsn a 1/16th of a turn, then concentrate on getting the hsn dialed(good smoke, good power and correct shifting). Then go back and fine tune the lsn for the best acceleration. How's your temps?
 
Last edited:
Back
Top