Rotax 912 Carb SafeSync

by Kevin Stewart in 912 / 914 Technical Questions 11 years ago

Fancy a simple method of single handedly balancing the carbs from the safety of the cockpit?

Well look no further, I've come up with this which I now use, if it is of use to anyone else then all the better.

See a video here:

http://www.youtube.com/watch?v=91b0NNI53-M

And parts list, drawings and photos here:

https://drive.google.com/folderview?id=0B6ytVYfsfAiNY3J3STVTUXZ5OEk&usp=sharing

If anyone has any ideas for improvement let me know.

Safe syncing!

Kevin

IMG009.jpg (You do not have access to download this file.)

RotationofIMG_0446.jpg (You do not have access to download this file.)

Page 1 of 7

Start
Prev
1
2
3
4
5
6
7
Next
End

Re: Rotax 912 Carb SafeSync

by jan kerstens » 11 years ago

jan kerstens

34 131 5

Hi Kevin,

Thank you for sharing this new invention.

What a clever design. I always adjust only the cable length of the left carb so two of these devices are in my opinion not necessary.
Having synched many times up till now it appears that cable adjustments have to be very small. Seen your video I am sure that the RPMs are just fine enough to ensure that.

More importantly it adds greatly to the safety of the entire operation.

I have started the construction of the KS remote Bing carb cable adjuster.

Best regards Jan

PS: KS stands for Kevin Stewart :lol:

Report
Re: Rotax 912 Carb SafeSync

by Kevin Stewart » 11 years ago

Kevin Stewart

5 184 0

Thanks for your kind words Jan.

The reason I made a dual channel system was that it allowed me to make fine adjustments of the idle speed. I find that on the Eurostar the idle speed is quite critical. If it is set too high you never land, you just float on down the runway!

Let me know how you get on sourcing the parts. Most of them I had lying around at home, the Lego I stole from my son ;)

I think that everything could be bought from eBay. The servos were given to me by a friend. They were specially made for a product where he works. I think that you could take a normal radio control servo and remove the control circuit (including the potentiometer) and just connect to the motor directly. I don't know whether they have and internal stops that would need to be dealt with.

Kevin

Report
Re: Rotax 912 Carb SafeSync

by jan kerstens » 11 years ago

jan kerstens

34 131 5

Hi Kevin,

How much torque (Ncm) has your servo? Do you have any specifications?

Thx Jan

Report
Re: Rotax 912 Carb SafeSync

by Kevin Stewart » 11 years ago

Kevin Stewart

5 184 0

Here is the spec:

Hitec HS-77 BB Torque (Kg.cm): 4.40
Hitec HS-75 BB Retract Servo BB Torque (Kg.cm): 6.60

Remove the stop and POT so it can rotate freely through 360°

Report
Re: Rotax 912 Carb SafeSync

by Hans Meier » 11 years ago

Hans Meier

2 15 0

Hi Kevin,

thanks for sharing Your invention!
Tack welding the nut is a great idea! Maybe soldering or just safety wire would do the job?
It seems useful to me also when adjusting without servo.
How precise should the synchronizer gauges match in the end? Some motorcycle guys prefer long hoses with fluid inside or some other "Carbtune Device" for more precise results.

Best regards Hans

Report

Page 1 of 7

Start
Prev
1
2
3
4
5
6
7
Next
End

You do not have permissions to reply to this topic.

Title	Category	Replies
Need to find 912iS Fuel Filter	General Tech Discussion	0
Need to find 912iS Fuel Filter	General Tech Discussion	8
pin cramp for ignition 912	912 / 914 Technical Questions	3
Garmin sensor kit for Rotax 912/915 iS	915iS Technical Questions	3
912iS Dual Flashing Lane Light at Startup	912iS Technical Questions	8

Rotax 912 Carb SafeSync

Recent Videos

Safety First!

ROTALK News

Prize Giveaway!

Log In/Out

Login