I'm attempting an engine swap in a 20 size Slow Poke. The old engine had the throttle arm on the left side of the engine well off the front/rear center line. The Saito .40 I'm trying to install has the throttle arm on the right side and much closer to the center line. My usual solution on a four stroke is to use a tiller bar mounted at the front of the engine bay, and then link back to the arm. I've already tried this with a 1/2" extension attached to the throttle arm with a ball link on the end (not shown). This was in an attempt to avoid sharp angles. There was also a ball on the tiller bar and a socket on each end of the link. The result of this set-up was a severe flexing of the plastic throttle arm and not much barrel movement. The sockets were well lube with a silicone lube. If anyone has experience with the Saito .40, or anyone else with an idea how to fix it, I would sure appreciate some help with a solution to this problem.

Throw the plastic arm away and make one out of aluminum. Get rid of the ball on the carb arm. Put a z bend in it and bend it to get it to line up with the aluminum arm you make. Use ez end with a set screw on the aluminum arm. Use the ball and socket on the throttle wire from the servo for isolation.

I got by with bending a horseshoe in the wire going to the thrttle arm. I used a Z-bend at the throttle arm. I used a slide clamp on the servo arm for adjustment. I've done it on several planes and seem to be getting away with it. I didn't use a tiller arm.

Enjoy,

Jim

Jim, the throttle arm on this .40 is tucked back in behind the cylinder. I've done it your way a few times and it has worked out well, but it was a straight out and straight back type deal. I would have to put about 3 bends besides the "Z" bend for it to connect. I've tried this before and got too much flex. I'll make a run tomorrow and round up some aluminum stock to fab a set-up like Kimhoff's. If I can't make this work, I'll try all the bends in some heavier music wire than I now have. Thanks for the ideas.

Here's what I came up with. It works well with no slop or binding. I still need to trim the screws securing the bent link at both ends. You can see I'm a fan of the Frank LLoyd Wright philosophy of "Form Following Function". If I may say this, there is a place on the gentleman at Saito who designed this throttle arm where I would like to clamp a pair of vice-grips.

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I use a set up similar to yours, Jim. No tiller arm/transfer bar needed. I can't take credit for the design. Another gentleman, Jim Garrahan, clued me in some years ago concerning this technique. It works every time.

Hi!
Guys!...I don't want to be rude in any way but ...all those linkages !!??
I would just rearrange the throttle linkage to the opposite side...much easier!


Regards!
Jan K
Sweden

Jaka, if you mean turn the carb around, on the three small four strokes I own this is not possible. The tank prevents a straight shot at the throttle arm. I've hooked up quite a few four stroke throttles and this is the first one that has been a challenge. The plastic throttle arm is so flexible, I could only get a straight push to work.

I use the 2-56 type pushrod and it is stiff enough for the horse shoe bend.

I thread this into Nyrod to go back to the servo where there is another 2-56 rod that goes the last bit to the arm.

Nyrod expands and contracts tremendously with temperature change and is sometimes frustrating. You will notice it as the temp changes during the day.

Enjoy,

Jim