What Headspeed???

[united737pilot]

Could someone please tell me what the proper headspeed for the 700 is?

[tcast305]

I'm running 1850 rpm, with an OS 91SZ with cline mod, on my 700. I would not run anymore than 1900rpm.

Thanks.

[raptorz499]

Why no more than 1900...should be fine with 1950...no!?!?

[tcast305]

raptorz499,

Thats on the high side. YS 91SR I would stick to 1850rpm and OS 91SZ no more than 1900rpm. Some will run higher, however you will start getting out of the motors peak power band.

Thanks.

[united737pilot]

Thanks guys. I appreciate the input

[raptorz499]

Well if you set the headspeed higher than the "optimum" peak power output of the motor at hover, then when you are bogging it down in really harsh manuevers you will be at a slightly lower motor RPM, which will give you peak power under load. Does this not make sense?

[Finless]

Idle up1 1900
idle up2 2000

And let me tell you! Any more than 2000 by even 50 and the tail grips DONT like it!
Time for a set of Kasama tail grips!

Bob

[raptorz499]

Sweet so 1950 would be ideal!!

[duceduc]

I'm running 1850 rpm, with an OS 91SZ with cline mod, on my 700. I would not run anymore than 1900rpm.

Thanks.
Whats a cline mod?

[JD]

Idle up1 1900
idle up2 2000

And let me tell you! Any more than 2000 by even 50 and the tail grips DONT like it!
Time for a set of Kasama tail grips!

Bob




Seriously? On a 90!? 2000?!! Perhaps your tail grips coming off would be the first clue this might not be safe....

[4cyclic]

I'm running 1825 on a OS and it's pretty responsive already.

[Finless]

Seriously? On a 90!? 2000?!! Perhaps your tail grips coming off would be the first clue this might not be safe....

Who said my tail grips are coming off???? Most the Align guys are running 1950 to 2K. What I said was getting much above 2000 is a problem since the 700 uses the same plastic thrust tail grip design as the 600... Most 600 guys are running well above 2000 (like 2100 is very common on a 600)!!! The diference is the larger tail blades on the 700 are loading up the grip bearings too much. I am going to get a Kasama tail for mine. I bet you will see a Align tail upgrade for this down the road.

Bob

[nwolsink]

Who said my tail grips are coming off???? Most the Align guys are running 1950 to 2K. What I said was getting much above 2000 is a problem since the 700 uses the same plastic thrust tail grip design as the 600... Most 600 guys are running well above 2000 (like 2100 is very common on a 600)!!! The diference is the larger tail blades on the 700 are loading up the grip bearings too much. I am going to get a Kasama tail for mine. I bet you will see a Align tail upgrade for this down the road.

Bob

QUK also has an upgraded tailbladegrip, since it is the same as the 600N

[tcast305]

Whats a cline mod?

duceduc,

Its a cline regulator installed onto the carb I have on my OS 91SZ (non pumped). Basically it turns a non pumped OS 91SZ motor into a pressurized setup like a YS 91SR, giving you consistant fuel delivery.

Thanks.

[cbdane]

I am going to get a Kasama tail for mine.

Hey Bob, just a quick heads up on the Kasama. The inside edges of the aluminum grips are closer together than the stock tail which prevents the slider from moving close enough to the hub. I had to machine a flat on each side of the slider to create enough clearance. I can attach a photo to this post a little later this evening.

Hope that this is helpful.

[Finless]

Hmmm OK thanks for the heads up!

Bob

[Tres Deuce]

I fly at 2020 or so with 710's and a 91 SZ.

I have over 12 tanks with no issues.

Jim

[jetpilot]

Bob so it is true that the Grips fly?....my god i don't like it


Luc

[Finless]

Bob so it is true that the Grips fly?....my god i don't like it


Luc

No they dont... Why do people keep asking me that? I never said the grips are flying off.....

Bob

[nwolsink]

Would this be a good setup:
1700 Normal - +/- 12
1850 Idle 1 - +/- 12
1950 Idle 2 - +/- 12

[Mercuriell]

Would this be a good setup:
1700 Normal - +/- 12
1850 Idle 1 - +/- 12
1950 Idle 2 - +/- 12

Looks good - quite lively :) - you will bog the motor on extreme collective but I assume you like screeching stops !

[CoronaL]

1920 per my tach on 91 YS ST. I was at 1960 but backed it off a bit. I tried 1880 too, but I liked 1920 better.

[nwolsink]

Looks good - quite lively :) - you will bog the motor on extreme collective but I assume you like screeching stops !

would 11 degrees of pitch be better?

[HeliSmith]

So if I am running 710 SB and 1900-2000RPM what pitch should I be after as maximum value? 13/13 as I usually do or do we tone down on a 90? Just seems like everyone is at 12/12.

[nwolsink]

So if I am running 710 SB and 1900-2000RPM what pitch should I be after as maximum value? 13/13 as I usually do or do we tone down on a 90? Just seems like everyone is at 12/12.

I found that I fly better myself with a little less pitch, on my 600 I use 11 to 12, not more