Pinion size? Bogging?

[Tachead]

Hey guys, what are you guys running for head speed and pinion? I am running the 17 tooth now at 3000 and 3200rpm for idle 1 and 2 but, am having bogging issues mainly at 3000rpm. If I run 3200/3400rpm it is much better. I am just wondering if I am a bit over geared and would see better performance at these head speeds with the 16 tooth pinion? I am a bit heavy too at 1165grams AUW but, still think I shouldn't have bogging with the Scorpion HK2520-1360kv/YGE60/Skookum governor combo I am running. Thanks.

[HeliSmith]

Well it depends greatly on how much pitch you are running. I am running governed off vbar @ 3000/3200 using the YGE/Compass motor on 17t and It loads up. If I mix too much cyclic with max 13 degrees pitch it will bog. If you want power drop back down to 16t and run it 100% wide open.. Headspeed varies during flight but it is more leverage favoring the motor, extremely efficient and it gives you that raw torque you might be missing. Governed electric is a different animal you gain consistent headspeed at the loss of raw torque and ultimate efficiency. This is by my experiences

[Tachead]

Originally Posted by HeliSmith

Well it depends greatly on how much pitch you are running. I am running governed off vbar @ 3000/3200 using the YGE/Compass motor on 17t and It loads up. If I mix too much cyclic with max 13 degrees pitch it will bog. If you want power drop back down to 16t and run it 100% wide open.. Headspeed varies during flight but it is more leverage favoring the motor, extremely efficient and it gives you that raw torque you might be missing. Governed electric is a different animal you gain consistent headspeed at the loss of raw torque and ultimate efficiency. This is by my experiences

I am running 13 degrees collective 8 degrees cyclic pitch. I only want to run governed, I will never go back to throttle curves. I love the consistency and lack of bog with the governor. It is just a setup issue I think. It barely bogs at 3200 and is flawless at 3400rpm. I just need to get it to bog less at 2800-3000rpm. That's what makes me think I may be geared a bit high? It is only at lower head speeds that it bogs. I greatly minimized the bog at 3000rpm by going up to 47 governor gain with 30 overdrive but, I would l like to get it better. I like to have my helis unboggable in full collective punch outs at very least. Maybe I am asking too much from this small heli? My Atom 5.5 is a beast and makes this Warp seem tame in comparison. Worst comes to worst I can run 3200/3400rpm or dump the 2520-1360kv and look for more powerful options. I am pretty sure it is just setup though as it doesn't bog at the higher RPMs.

[HeliSmith]

Yeah that's a wide rpm range to want to govern. When I want the most power I go for 3200 and when I want to cruise for 4:30 I use 3000. Some techniques I use are similar to an auto, if you've heard the pros over speed on the way down. I can gently gain height then give it a pop down, gather headspeed and then use it in that way.. So it's a bit of an illusion.

[Tachead]

Yeah, I would like to run 3000/3200rpm just like you but, hope to have zero bog in full collective punch outs at both RPMs. The 17 tooth gives best external governor performance at 3200 and ok so-so performance at 3400rpm where as the 16 tooth gives best performance at 3000 and so-so at 3200rpm by Mr. Mels. I want to fly mainly at 3000 and 3200rpm like you so, I think I might get better performance with 16 tooth(its hard to say) as the SK governor really doesn't need much headroom. I just don't want to waste my time swapping pinions if it isn't going to help. Is anyone running the 16 tooth for 3000/3200rpm governed? How does it perform? Thanks

[Tachead]

I am also running my motor belt on the tight side. I am not sure if that is robbing some power too? I run the tail belts on my helis just tight enough so they don't skip but, have the motor belt quite a bit tighter then that as I was worried about slippage with so much power and high governor gains. I am not sure how tight to go with the motor belt really as this is my first model with a motor to main belt.

[Jeff_Barrett]

Treat it like the tail belt, but just a hair more snug ... just tight enough that the belt won't skip on the pinion or main gear.

[HeliSmith]

I run my belt like Jeff explains. Sometimes it's about the perfect battery for the machine also. I haven't had a chance to experiment with different brands only the Pulse 1350 35c.