L.A. Choprods Internal Throttle Kit - Hide It Like You Stole It

L.A. Choprods Internal Throttle

1. The L.A. Choprods internal throttle kit includes (clockwise from top left) inner slider tube, throttle rotor tube, double-row bearing, cable guide, roller bearing sliding pin, and end cap.

2. After cleaning (barely) the rusty patina from the handlebars, they were put in a vise...

3. ...before measuring and marking 3.7 inches from the end of the bar. The inner slider tube will occupy this cut part, making both sides of the handlebars the same length. It's very important to get this measurement correct and to make sure that it's the side of the handlebar (usually right) where the throttle will go.

4. Moving over to the Maxisaw, Gard cut off those 3.7 inches. That's why it's important to get the measurement and the side correct. This cut could be made in your garage with a hacksaw if a Maxisaw isn't available.

5. Following the cut, the end of the bar was sanded to clean any rough spots.

6. Likewise, the inner lip of the handlebar was cleaned up with a deburring tool.

7. Moving the bar back to the vise, Gard measured 1.725 inches from the end and made a mark before using a spring-loaded punch to mark the spot...

8. ...where he drilled a 9/64-inch hole.

9. We verified the location of the hole and then tapped it to 8/32-inch. This would be used to secure the inner slider tube to the bar with the supplied 8/32 x 1/2-inch set screw.

10. With the bars ready to go, Gard moved on to the easy task of assembling the throttle assembly by sliding the throttle cable through the cable guide. You'll notice the end of the cable is bare. It's supposed to be that way and can either be purchased bare, or you can just cut the "knob" off any throttle cable that mates to your carb. Make sure you plan how and where the throttle adjustment will go, as the stock-like adjuster no longer resides up by the bars. An adjuster can be positioned under the gas tank or close to the carb. It's also possible to carefully measure the cable with the bars installed and cut the throttle end of the cable to the length needed. Make sure you check measurements with the bars turned in each direction.

11. In this case, a Barnett cable was used. It comes with a brass sleeve that slips over the end of the exposed cable, which prevents fraying.

12. Then the cable was slid into the roller bearing sliding pin, before...

13. ...tightening the cable with an Allen wrench.

14. The parts already assembled were then slid into the inner slider tube.

15. At this point, the handlebars were retrieved and the throttle cable slid into the right side...

16. ...until the hole in the inner slider tube lined up with the hole from steps 8 and 9.

17. Once lined up, the set screw was screwed in until just below flush with the handlebar.

18. The double-row bearing was readied before...

19. ...popping it into the hole in the inner slider tube.

20. The outer throttle rotor tube was slid over the inner slider tube, lining up the groove in the outer sleeve with the bearing. Of particular note is the way the groove in the outer sleeve was machined: It only requires 160 degrees of rotation to go from closed throttle to wide open. No more trying to twist your arm to China to get the throttle open.

21. The final step was installing the end cap and securing it with an Allen bolt. If needed, there is a set screw that can be used to secure the outer sleeve to your grip, although it's often not necessary to use it.

Creating a bike that's sanitary and uncluttered is one of the main stylistic points for many builders and owners. Over the past few years a big trend has been to hide every conceivable nut, bolt, wire, oil line, and any other parts of the build process that go into making a running motorcycle. It usually takes a ton of work to give the impression of simplicity-certainly more effort than just bolting everything together and calling it a day.

A relatively easy modification many owners opt for is hidden handlebar wiring, where the wires are run inside the handlebars. Even brake and clutch lines, along with master cylinders, can be concealed within the bars. A particularly cluttered situation exists around the right grip-with dual throttle cables exiting the throttle, then snaking their way in an arch under the gas tank before mating up to the induction unit (um, carb or EFI throttle body). These push/pull throttles have one cable for opening the butterfly and another to close it. The push cable can close the butterfly in the event the pull cable breaks and the return spring on the butterfly fails. Many a rider has set up his or her scoot with only the pull cable with no ill effect. When you let go of an open throttle, the spring is what returns it to idle position.

Where are we going with this? Well, we got our hands on the latest internal one-cable throttle assembly that conceals the cable within the bars. L.A. Choprods has designed an internal throttle based on customer feedback relating to earlier versions of internal throttles. The company lengthened the outer sleeve, making it easier to secure a grip, and added another bearing to the assembly to enhance the performance of the throttle. Outer parts are made from 1018 mild steel, while all internals are CNC-machined from billet 6061 aluminum and anodized for corrosion prevention. It fits standard 1-inch handlebars and 1-1/8-inch bars with an optional outer sleeve. The handlebars will require some modification that should take less than a couple of hours.

We visited Gard Hollinger and Jay Brown at their L.A. Choprods safehouse hidden within the vast Los Angeles metropolis. The Choprods throttle retails for $170, but we've negotiated a deal for you to save 20 bucks if you mention you saw it in Hot Bike.