Da Mutha of invention

deacon · #1 (**permalink**) 07-30-2008, 06:35 AM

I need a cheap easy to build very basic simple throttle control. One anyone can make from scratch without special tools.

Lets review what I know.
1. The throttle control is for the weed eater type engine.
2. The throw is no more than an inch.
3. I use a spring on the cable end so there need not be one in the control.
4. Anything that can pull the cable and inch will do.
5. The cable sheath can be taped to the handle bars so the control does not need a stop.
6. Has to be something that can be worked with my hand on the handle bar end for control.
7. rougher looking the better lol...

I know I can use a shifter or a brake lever but I want to make something from scratch for this build.

I have toyed with the idea of pvc over the handlebars for a twist throttle. The spring on the motor end of the throttle would be the return and also hold in it place maybe.

jasonh · #2 (**permalink**) 07-30-2008, 12:54 PM

You could hack up one of the on/off bar things that are on lawnmowers.

Or the simplest is just a piece of string that you pull

Really I can't think of anything decent besides using a brake or shifter like you said.

**Bikeguy Joe** · #3 (**permalink**) 07-30-2008, 02:23 PM

A small piece of wood with a couple of holes drilled in it and a porch sping- only smaller for the return.

eDJ · #4 (**permalink**) 07-30-2008, 02:30 PM

What I think I'm going to use on my project is a shift device that came off the handle bars of a mountain bike. It has like a 2 1/2 inch long lever that sits along the top of the handle grip. I gave a buck for it as it was in a box full of shifters where the shop has bulk parts they sell. By using a universal cable (these come set up for derailer controls or brakes so look at the end of the cable to see what is molded to it for an anchor) for a derailer control the cable could be routed back to the rear mounted motor to where the end of the cable hosing would be mounted in a clip to hold it firm to something.......and the bare end of the cable run thru the throttle bell crank or joined to the carb's cable system so it works freely when the lever at the handle bar grip is moved left and right.

On my shift lever that I'm using for the throttle I can adjust the friction tension on the lever movement. So if the tension is adjusted to the "sweet spot" where the throttle lever would take little or no effort to move and stay where ever it's placed thus maintaining the engine speed I want.

Just below the handle grip is my brake lever so my right thumb is free to control the throttle lever.

Short of having a source for an inexpensive twist handle grip for the throttle this is the next best thing. I'm sure some the Chinese kits provide them. If I could buy an expensive one for like $5 bucks that's the route I'd go. (I'm sure alot of DIY scratch builders would be right on top of such a source)

deacon · #5 (**permalink**) 07-30-2008, 07:27 PM

While looking around in my own personal landfill (aka shop) I came across not one but two triggers from week eaters. there are nothing more than an odd shaped lever. They can be used along with a modified pipe clamp to make a throttle I think. I'll have to check that out since I would get one free with evey weed eater I bought to build a bike for myself.