Steering cable setup

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09-30-2010
ToneDef

Steering cable setup

I'm in the process of setting up cable pulley steering and had a question.

Are the two additional pulleys on the motor bar really necessary? I understand it makes the steering easier, but it would simplify things without them. Can't I just run the cable off the drum, through the pulleys in the coaming, and back to the motor bar, with a spring on one side? Effectively skipping the two pulleys on the motor bar and anchoring to the bar rather than returning to and anchoring to a point on the coaming. Or would the steering be too difficult to be effective?
09-30-2010
hydroc888

Cable steering

If you are talking about using this setup on your glen l in your vidio you are going way to fast for a system like you are talking about. It will make your stearing way to fast and hard to turn . Look at it like a set of rope falls , the more parts you have in the line the easir it is to pick something up and slower. Dont use any springs your motor can wobbly back and forth and cause you to lose control of the boat.
09-30-2010
JohnsonM50

Quote:

Originally Posted by ToneDef

I'm in the process of setting up cable pulley steering and had a question.

Are the two additional pulleys on the motor bar really necessary? I understand it makes the steering easier, but it would simplify things without them. Can't I just run the cable off the drum, through the pulleys in the coaming, and back to the motor bar, with a spring on one side? Effectively skipping the two pulleys on the motor bar and anchoring to the bar rather than returning to and anchoring to a point on the coaming. Or would the steering be too difficult to be effective?

You could & you have the differing cable length per position with the spring covered. On one hand if this is for the Glen-L / 15 it would likely be adequate & steerable but the indirect method is safer. The best way to decrease wheel turn per boat turn is to use a larger dia hub. 3 1/2" - 5" - 7" Are what Ive seen available. As you get faster you'll want steady, safe -dependable steering
09-30-2010
hydroplay

It's all about leverage and mechanical advantage. Putting pulleys on the steering bar with the cable end anchored to the cockpit side will slow the steering down by 1/2 but it will also decrease the effort you need to turn the wheel. The price you will pay is that now you have to turn the steering wheel twice as far to turn the motor a given amount. Good or bad? It depends on your strength, steering hub diameter and engine torque. This is one of those questions with no correct answer- you have to figure it out for yourself. In general low horsepower rigs use direct steering, larger ones use indirect but there is no absolute cut-off inbetween.
09-30-2010
ToneDef

The hub is small, apprx. 3.5" in diameter. I will try direct first because I would like to keep the wheel turn per boat turn to a minimum. Plus, I can always just replace the cable if I don't like it!
09-30-2010
JohnsonM50

Quote:

Originally Posted by ToneDef

The hub is small, apprx. 3.5" in diameter. I will try direct first because I would like to keep the wheel turn per boat turn to a minimum. Plus, I can always just replace the cable if I don't like it!

I had it direct on my Airborn for awhile & found that when up to speed it was fine, gotta be careful either way. Oddly enough it was weird going slow with it, a small steering correction could put ya 30 degrees off LoLs
10-01-2010
Chairman

We run steering cables direct to the steering arms in our smaller OPC classes: Mini GT (25hp); GT Pro (35hp); and Sport C (40hp). I use 5-inch steering drums on my boats, which makes for very quick steering.

On the other hand, we use foot throttles in all these classes, so are able to keep two hands on the steering wheel at all times.
10-01-2010
JohnsonM50

Quote:

Originally Posted by Chairman

We run steering cables direct to the steering arms in our smaller OPC classes: Mini GT (25hp); GT Pro (35hp); and Sport C (40hp). I use 5-inch steering drums on my boats, which makes for very quick steering.

On the other hand, we use foot throttles in all these classes, so are able to keep two hands on the steering wheel at all times.

From seeing the clips of the tunnels turning so quickly it makes sense to use direct hi-response steering.
10-01-2010
yeeeha

steering

I have done it both ways. I races SST-60 and Sport E. Personally I liked direct steering (without the pulleys on the motor bars). I would mention that I typically raced short sprint races and when I raced in marathon situations, I would go back to indirect steering.
10-02-2010
ToneDef

Rigged the steering up direct today using 1/4" SS flat bar for a motor bar. Even though the hub is very small (it's an old helm I had laying around) it still steers with more response and in a tighter radius than I will ever need to go while at speed. Need to find some SS cable though, all I was able to get my hands on is plastic coated steel zinc plated cable, but I am only in fresh water for now so it will suffice for a short time.
10-02-2010
JohnsonM50

Quote:

Originally Posted by ToneDef

Rigged the steering up direct today using 1/4" SS flat bar for a motor bar. Even though the hub is very small (it's an old helm I had laying around) it still steers with more response and in a tighter radius than I will ever need to go while at speed. Need to find some SS cable though, all I was able to get my hands on is plastic coated steel zinc plated cable, but I am only in fresh water for now so it will suffice for a short time.

Brown Tool & machine has SS cable & rope for steering. Forgot to mention another way to adjust steer ratio to a small degree is steer bar length.
10-03-2010
Chairman

I forgot to mention: we don't use any springs in our steering systems. Shape and/or postion the steering arms so that the ends -- where the cable attaches -- are in line with the engine's tilt tube. This way, when engine tilt changes, cable tension stays the same.

http://www.dillon-racing.com/mini-ve...truction57.jpg

http://www.dillon-racing.com/mini-ve...truction58.jpg
10-03-2010
JohnsonM50

Quote:

Originally Posted by Chairman

I forgot to mention: we don't use any springs in our steering systems. Shape and/or postion the steering arms so that the ends -- where the cable attaches -- are in line with the engine's tilt tube. This way, when engine tilt changes, cable tension stays the same.

http://www.dillon-racing.com/mini-ve...truction57.jpg

http://www.dillon-racing.com/mini-ve...truction58.jpg

Ive been doing it different, also w/o springs. Aligning the pulley pivot with the steer pin center line instead. This does make the tilt up tight for a second till over center but theres enough flex. On most motors you cant align both tilt & steer exactly. I wonder if in between would be good. On the OMC shown thats about a 4" to 5" difference to split.