Very slow revving on low power engine (inertia 0)

Hi, I am currently trying to make a portable generator with one cylinder and around 1.3 horsepower. That all worked, the engine is running and it even drives (i ported it to the pigeon for now) but it revs very slow. Due to the very low power I already had to set the dynamic and normal friction pretty low for it to even run, but even with the inertia set to 0 the engine revs rather slowly. Is there something I am doing wrong, or is this just BeamNG not being ideal for such small engines?

here's my engine settings:

"mainEngine": {
"torque":[
["rpm", "torque"],
[0, 0],
[1000, 3],
[2000, 4],
[3000, 5],
[3600, 6],
],

"idleRPM":1200,
"maxRPM":3600,
"revLimiterRPMDrop":0,
"inertia":0.001,
"friction":0.04,
"idleRPMRoughness":250,
"dynamicFriction":0.0001,
"engineBrakeTorque":0,
"starterTorque" : 10,
"starterMaxRPM" : 800,
//"burnEfficiency":0.8
"burnEfficiency":[
[0, 0.98],
[0.05, 0.80],
[0.4, 0.75],
[0.7, 0.60],
[1, 0.49],

 

Okay I managed to fix this with the help of AxGojusanBechi on the Modding for Dummies discord. Turns out the transmission (logically) ads some inertia as the the flywheel and pressure plate are directly connected to the crank and have a mass. I removed the transmission and all my problems were fixed! Hope this helps someone sometime.