What rpm on take-off should i have!

[stertwiel]

Ok, so depending if you got a VB prop / ground adjustable,fxed, and what your needs is, climb or crouse!, my cinario(hoop dis reg gespel), i have a kitfox classic 4, with round cowl.I have a fixed pitch FITI prop, very smooth, very quiet, good looking, but want climb performance.I get 4850 rpm on take off, max rpm in level flight is 5200rpm, going into the red arc(eish), 100hp ratex.So obvious nice prop for crousing, 4400rpm, 85 knotts.Reading american reviews, they recon there is a SB out stating a min of 5200 rpm static on Rotex.I can not seem to find the SB on that.Any help on the SB, or advice on rpm for take off and level flight.My opinion, i need 5200rpm on the climb at least, to warrent my 100hp engin!.Advice please!

[KFA]

Redline on 100hp is 5800 for 5 min and max cont is 5500. I would not go for less than 5300-5500 static, that should give you about 5500-5800 on the climb out. Remember the 100 horses is only at 5800, so you want to get as close to that as possible but getting the horses will make you loose cruise speed.

[Triker]

I also have a question regarding my rpm on a 582 Cobra
When static my max rpm is about 6800 and also when taking off (approx thereabout aswell)
Straight and level cruising is about 5500 1 up at 60mph and 2 up, about 5700 58 mph

Does this sound healthy to you guys? I just feel its a bit too high.
Best regards

[Goose]

I get 5200 static in my 100hp Kitfox

[JvTonder]

5300 - 5400 static on the 95hp rattex, never even come close to max 5850

[BOOMARANG]

Hi Triker

I have an Aquilla 582 with an Aquilla 2 wing. I weigh 110gk and fly at 48/50 knots on 4900rpm, one up and the same at 5300rpm with a pax of 94 kg and a full tank. I have a warp drive prop and max revs on take off is 6000rpm. my consumption is 11/12lph and wing set on the second setting from the front, ie the second fastest.

The pitch on the warpdrive is set (I think) on 18 or 20 degrees and the max the ratex wil rev is 6000. But I have more then enough power, good climb end excellent economical cruising. Fly from vereeniging where the alt is 4840ft.

Revs for any motor is a killer and I am prepared to fly a couple of MPH less if it means saving 500 revs a minute......in an hour its 30 000revs less in wear and tear and fuel.As I mostly fly with friends that are a bit slower in 503's is it is ideal for me.

[Triker]

HI Boomarang

Thanks for the info. I must say that many of your numbers correspond to mine
I also have my wing second clip from the front and burn about 10-12 liters per hour at speed 60Mph
As you mentioned slowing down a bit saves about 1000rpm's

I was just worried that my 582 will exploded if it revs 5800 at take off, but according to the performance graph this is the max HP output (approx)

Best regards

[cjkrit]

I think 6800rpm is too high for the 582. As far as I know the max rpm on take-off should be 6350-6400.

Twostrokes in general will tolerate high rpms much better than 4-strokes and in fact I think is beneficial - these machines want to work.

[bobthebuilder]

Rotax 582 - Manual Quotes:

6800 RPM Max (5 Minutes)
6500 RPM Cruise Speed.
Operating Temp. 65-80 Deg C

The engine was designed to run at 6500 RPM continuously.