Idle Screws

[bklf7]

I bought a used set of stock carbs and want to install my idle screws from my old carbs, the ones for the tors removal kit. The thing is I bought the wheeler with them already intalled and want some detailed instructions on how to install them on my newer carbs.

[fastrthnu]

I bought a used set of stock carbs and want to install my idle screws from my old carbs, the ones for the tors removal kit. The thing is I bought the wheeler with them already intalled and want some detailed instructions on how to install them on my newer carbs.

 

Banshee Idle Kit

Installation Instructions

Included in this package are the following parts:

 

 

1- Size #6 Drill Bit

1- 6mm X .75 Tap

2- Brass Idle Screws

2- Idle Screw lock nuts

4- Pages of Installation Instructions

including the Limitations of Liability Notice

Please find and identify all these parts before continuing this installation. Do not proceed without the proper parts. We certify that all parts listed above are included in this package. If for some reason you find something missing you must file a claim with the freight carrier (usually UPS). Please refer to our Limits of Liability on the last page of these instructions for more information.

 

Procedure:

 

Locate the idle screw bosses on the outside of the carbs. After you have identified these bosses you can remove the carburetors completely from the machine. You can just unscrew the carb tops and pull out the slide assy. complete and leave them on the bike. Then, you must disassemble the carb bodies completely.

 

The left carb has its boss on the left side and the right one on its right. If you look on the right side of the left carb and the left side of the right carb, there will appear to be a drilled and tapped hole that looks very much like an idle screw hole. I'm not sure what these holes are for, but rest assured, these are NOT the Idle screw holes. If you are not sure which hole is which, call us and we will help explain it. The ones you want are not threaded.

 

 

 

Be Careful with this next step!

Using a drill press or very steady hand drill with the supplied #6 drill bit, finish drilling through the idle screw passages into the throttle bore but NOT through the other side of the throttle bore. There is perhaps only a quarter of an inch of thickness to drill through.

 

Next is the only modestly difficult part, but it is necessary, and must be done carefully and correctly. The Idle screw boss casting comes finished off at an angle. This must be filed, milled or ground flat (perpendicular to the idle screw hole) so that the Idle screw lock-nut will have a flat surface to lock against to secure the Idle screws. On some carbs, you might have to machine it a little shorter as well. The finished measurement is about 3/4 of an inch (or 20 mm) from the outside of the carb to the lock nut surface.

 

Now that you have finished these steps, you can screw the supplied (6mm X .75) tap through the idle screw hole fully. Be sure to use a good oil or taping fluid specifically for aluminum for this job. This way you will get a good clean thread. We have heard horror stories of people who do this without oil, and break off the tap in the carb. Then you either buy a new carb, or E.D.M. the tap out, either option is expensive.

 

Now, and most important is to de-bur the hole. You can use a sharp knife on the inside hole and a chamfer tool on the outside of the hole to put a nice 45ochamfer and remove any remaining filings from the drilling or tapping process. You must also use a little fine (like 400 or 600 grit) sandpaper inside the throttle bore to smooth the edge of your new hole so that there will not be any burrs to stick the throttle slide. Please test-fit the slide in the bore of the carb before final assembly to insure it slides freely. Stuck throttles while riding are no joke.

 

 

You must make certain of this point!

Now please clean thoroughly the entire carb of all chips and dirt. Only after everything is perfectly clean and all chips are gone, (use compressed air to thoroughly blow out any and all chips & dirt) can you screw the idle screws into the carbs, (don't forget to put the lock nut on first) and re-assemble the complete carb paying particular attention to set the float level at 21mm.

 

With the Idle screws backed out a little, so they don't touch the slides, install the carbs on the bike. Be sure to install the slides properly. Specifically, with the "cut-away" facing the rear of the bike, and the big 45 o notch on the bottom facing the Idle screw. This is the ramp that the idle screws use to hold the slides in the idle position. Please confirm that the slides do in fact "bottom out" in the throttle bore, and that they lift with the turning of the throttle, at precisely the same time. (synchronized)

 

Now, start the bike and warm it up thoroughly. While holding the throttle at the desired idle level, screw in the Idle screws until they just start to touch the slides and raise the RPM, then back off about 1/4 turn, and secure the lock nut. do the same to the other side and you're done! The Idle rpm should be around 1400 rpm, or as low an rpm that is stable when the engine is warm

 

Finial Check:

 

Turn the handle bars from side to side to the full lock position to insure the RPM does not fluctuate. If it does, re-route the throttle cable so it doesn't hang up on anything.

 

Double check that the idle screw lock nuts are tight.

Replace all the airbox equipment and check for air leaks

and proper fit on all components.

Double check the clamp on the carb manifolds for tight.

[FireHead]

I have an instruction sheet from a Motion Pro idle screw kit. If after reading the response above, you still have questions, I would be happt ot scan the sheet and post it up here. :thumbsup:

[bklf7]

I think that will do for now. I was really looking for the right size drill bit and tap. Thanks for the info guys.