Big Ruckus Idle-Mix

[Phil_R]

Pilot screw adjustment (idle-mix) is usually a bit lean on machines "as delivered." My BR was no exception... original pilot screw setting 1-1/2 turns open, current setting 1-3/4 turns open.

After finishing the 600 mile valve adjust, a 10 mile test ride brought the engine up to full operating temperature. A digital tachometer was used to set idle speed to 1500 RPM and to adjust pilot screw for "highest speed." (idle speed then adjusted back to 1500 RPM)

From the original 1-1/2 turn pilot screw setting, to the 1-3/4 turn setting increased RPM by about 50...

Now the bad news... ES-322 Digital Tachometer and Honda tool #07MMA-MT3010B. Maybe you are sensitive enough to discern a 50 RPM change without the tach, I'm not. The Honda tool, (adjust pilot screw) many have substituted a "home made" tool by denting / flat-spotting a .22 calibre LR shell to match the D shape of pilot screw.

If you are keeping the intake and exhaust "stock" on your BR... this pilot screw adjustment is about all the carb modification needed.


ES-322 Digital Tachometer sitting on BR seat, inductive pick-up attached to sparkplug wire. Tach uses internal batteries, no other attachment to engine needed.

[tedsmini]

How much stuff did you have to remove to get to the valve cover? Did the valves need adjusting? If so how much? I am at 1400 miles and don't notice any difference in performance except I gained a little top speed and some acceleration when I went to synthetic Amsoil I just clicked on your BR page and the job you did on the info and pix was fantastic, it answered all my questions except how much did the valves
have to move?

[Phil_R]

Valve clearance (intake and exhaust) is listed as 0.005" for Big Ruckus. Since the adjustment is performed externally, no actual measurement is made.

Assuming the adjustment procedure provides the recommended 0.005" clearance... When checked / adjusted @ 600 miles the intake clearance was 0.005" before adjust, and exhaust was "tight" at 0.002" ~ 0.003".

Both valves set to 0.005" @ 600 mile service, using factory adjust procedure. I suggest checking valve clearance @ recommended "break-in" service... earlier if you experience any problems.

[leek]

Could you tell me where you purchased the tachometer. I can't find that particular model on the internet. Thanks

[Phil_R]

leek said:

Could you tell me where you purchased the tachometer. I can't find that particular model on the internet. Thanks

I purchased my tach on eBay... this is the company:

USAtoolwarehouse.com with a direct link to the tachometer.