Hello, I have a hong nor truggy with an SH.28 engine. I run 16% nitro fuel and have problems tuning it. Someone with the same engine please tell me how many turns out the HSN and LSN is. Thank you, much appreciated.
there is no magic settings. One person's settings may be completely different then what you need because of altitude, air temp, humidity, etc. Fuel also makes a difference as you may be running 16% fuel with 15% oil, and someone else running 30% fuel with 6% oil. Know what i mean?
Its best to just set the needles at factory settings, then tune from there. Here is what i do:
Start the engine...let it get a bit of heat in it.. pick it up and rev it up a few times to clear it out. Quickly set it back down and pinch the fuel line off as close to the carb as you can. Count how long it takes to start running out of fuel. Ideally you want it to take about 4-5 seconds then start slowly picking the revs up as its leaning out. Adjust needle accordingly. If it instantly tries to die.. your low is too lean. If it takes longer then 4-5 seconds, its too rich.
After that.. tune the high needle for best performance. After you get the needle set so that it has a good crisp topend, and '4 strokes' when you let off the throttle. You should be set. You may have to richen the low needle back up slightly after this.
In my opinon i would be running 20% on break in and 30% after it'll run better on it and a little easier to tune.When you got a high oil content its good for the lubrication but makes tuning a little rougher because technicly its harder to burn.