Leopard Hobby 4074 2200kv "D" or "Y" wind

[Old School]

At present I have a smash Shark to which I fitted a Leopard Hobby 4074 2200kv brushless motor, taken from a new HK "Osprey". OSE store and Leopard Hobby website show the 2200kv model to be a "Y" wind thus timing should be around 15 when programming. For some inexplicable reason I believed the motor to be a "D" wind and set the timing to 0 degrees. How does one know whether a Y or D wind motor?

The boat is having trouble getting up on plane and I am now thinking would the incorrect timing contribute to the planing problem as the motor just does not seem to rev as high as I believe it should? The boat just seems to be lacking power. The motor is new and the Turnigy 180 amp ESC is also new.

[martin]

That motor is a Y wind, all Leopard 4074 motors are Y winds.

[TRUCKPULL]

That motor is a Y wind, all Leopard 4074 motors are Y winds.

NO they are not all "Y"
1650 - "D"
1800 - "D"

Larry

[martin]

Yes I forgot about those 2 kv's that OSE keep, apologies.The 2200kv is still y wind.

[Luck as a Constant]

Highly doubt your timing is the culprit for your issue there. Def set that to 15 degrees and you’ll get less heat for sure. What prop are you running?

[CraigP]

Old School, I have that same motor/ESC in my DF 29 Mono, on 4s. I run an M445 on it and it’s quick enough with no heat issues. I have good results with 12 degrees on that combination. I also have the hull trimmed so just the last 1” of the bottom is in the water while running straight. Hull drag and wrong prop really bring on the heat quick! Your Cat should have less drag than my Mono

[MarkF]

It sounds like your prop is too small and why it's not getting on plane. What size is it? That motor can swing a 442 to 447 prop. Adding timing gets you more mph ( 3 to 5 mph) at the expense of heat. Not the other way around. 15 deg. is high timing and not good for longevity of the esc. The motor doesn't care what the timing is set at but will get hotter as timing goes up. It all depends on your prop size, and 15 deg. might be fine with a small prop but will get esc and motor hot as prop goes up. I have raced that size motor using a 447 prop and 7 deg. timing just for a reverence. Now that is a hot set up and if you want more runtime then go with a 442 to 445 prop.

Mark

[Old School]

I have tried with an M442 and yesterday I tried with an X440 with same result. The boat raises its bow up high but just does not have the power to get the tail up. As a precaution, last night I lowered the height of the stinger as low as possible but as yet not tested it. I am awaiting a slow boat from China with an X440/3 propellor.

[photohoward1]

How many cells?

[martin]

You could have one of the troublesome Turnigy 180a esc that goes straight into low voltage mode, this was a problem a while back on this forum for some that had these esc's. All sorts of things were tried to overcome this problem, even switching off the lvc didn't cure the problem.

[Old School]

I am using Turnigy Graphene 5000 mah 4s 45C batteries. The ESC was only recently purchased from the local Australian HK wharehouse so I assume fresh stock.

I adjusted the timing to approximately 12 degrees and the motor seemed to maintain unloaded rpm without cycling. When set at 0 degrees and the throttle wide open it would accelerate to a lower level and then accelerate further to a higher level. Perhaps wishful thinking but it did sound healthier on the advanced timing setting.

[MarkF]

If your bow is riding high, It could be your strut is not level or pointing up a little. Try putting a little negative on the strut or pointing the prop down a little and that should help get the nose down. Might also try getting weight more forward too. Going smaller then a 442 is not your answer to your problem. A 440 3 blade will just give you less speed and more runtime.

Mark

[Old School]

Many thanks.

[CraigP]

I’m sure you know you’re way around a good Cat setup, but the problem sounds like it’s in the setup. Have you double checked all the basics? CG at 30%, Strut neutral and centerline of prop shaft 1/8” above the back of the sponson line? Even if the ESC is throttling, it should pop up on plane for at least a short distance. My first prop was a Grim Racer I was using on my hydro when I first completed it. It was the first blade that I shaped myself. It did exactly as you describe on my hydro and my mono! I got a Cat some time later and thought, what the hell, try it out. It did exactly as you are describing. Put another blade on it, only change, and off it went! I still have not identified exactly what I did wrong on that blade. Showed it to a racing friend of mine, he thought it looked decent enough, but it wouldn’t push ANY boat...

You gots to let us know what you find! We are all really curious....

[Old School]

Craig,
the hull was reinforced thus additional weight. Secondly, the first prop tried was a TFL modified 442 with absolutely no low torque tongue. The stinger is parallel to the keel and since the last dismal performance with a 440 prop (which worked perfectly on a hydroplane) I have lowered the stinger approximately 2 mm to hopefully help the hull out of the hole it digs itself when power is applied. As initially tested the hull was more a displacement hull with the bow high and absolutely no speed at all, not even enough to allow the cooling to work.

Now that I know that the motor is a 'y' wind I have upped the timing to approx. 12 degrees and await a further prop to test, a 440/3 which is known performing prop on this hull with a 4074 motor. The motor does seem to sound better with the new timing. I have shifted the battery aft after relocating the ESC to the left side rear bringing the C of G further aft approximately 1.25". A test will be carried out in a week or so.