Carls Konged '78 CB750

Spent some time over at Carl's today to help get his bike back on the road. Needed lots of love after being his sole mode of transportation for a long time and then shoved in the corner for a few years like an old broom.

Just a few things off the checklist (stock k8 engine):

Set points:
Gap 0.012" to 0.016"
Static set 1-4 timing on F-mark with ohmeter
Static set 2-3 timing
Lock plate and roll.

Valve Lash:
E.O.I.C method
Intake 0.002"
Exhaust 0.003"

Set cam chain tensioner:
Push kicker to get tension on the front of the cam chain and slack on the rear. Loosen lock nut on tensioner and back out the set screw. Listen for movement in the tensioner and lock down the set screw and lock nut.

After setting the valve lash, I successfully snapped a Tappet cover off. Good word of advice: Just snug the Tappet covers down lightly. This one was fatigued or already broken because I didn't even get the gasket seated to the valve cover before it popped.

Meanwhile Carl replaced the fuel pump in his car. Lovely day.

Rock Flute Specifications:

For my own notes and for those interested, here are the specs on Rock Flute.  I'll update this as things change... because they always do. For instance, the green paint in the picture is actually a brighter green than the color code listed below.  I will update the picture as soon as the bike is repainted.

Engine:

10.9 to 1 CR

1978 CB750 F bottom end

1976 K model cylinders, Decked

1976 K model Head, Stage II porting, decked by Mike Reick

                33.5 mm OS intake valves, stock exhaust valves

                Megacycle 125-75 cam, 0.005” Int/Exh tappet clearance, 105 int 104.5 exh lobe centers, no adv.

                                (More cam specs in chart below)

                Adjustable cam sprocket

                HD Valve springs and titanium keepers

                Late model cam towers with unbolted early model rocker shafts

Wiseco 836 forged piston kit

CycleX Super Rods

New primary chains installed

Reinforced valve cover with cam tower stabilizers

Transmission/Final Drive:

F model transmission, backcut with close ratio 4^th and 5^th gear

             Primary: 1.708:1
            1^st:           2.500:1

            2^nd:          1.708:1

3^rd:           1.333:1
            4^th:           1.133:1

5^th:           0.969:1

Barnett Clutch plates and springs

Drilled clutch basket with oil grooves for added oiling

Final Drive: 17/48 2.82:1

Ignition:

Dyna 2000 ignition with 3 ohm Dyna minicoils

Total Timing Advance: 35*

Timing curve: 4 (changed 6/12/15 from 5 which may be causing low/mid stumble)

Rev limiter: 10,500 RPM

NGK DR8EA 5 kohm Resistor type spark plugs @ 0.036” (resistor plugs used to eliminate noise in digital tach and increase spark duration)

Fuel/Intake:

Ramflo Filters

Sudco VM29/CB750 Adapter boots with vacuum ports

Mikuni VM29 Smoothbore Carburetors

               Mains: 120

               Pilots: 12.5

               Air Jets: 0.9

Air Screws: 1.5 Turns

Jet Needles: #5DL31 with clip @ #5

Needle Jets: 0-6

Throttle Valves: 1.5

Float Height: 23 mm

Exhaust:

4-2, 2” long baffle with 1.25” inner diameter

Frame:

Cycle One Manufacturing rigid

2" forward

4" up

36* rake, Harley 1" neck

5" ride height

Paint: Sikkens Rally Black

Body:

Fuel Tank: 1969 Triumph Tiger Daytona 500

Rear Fender: 5" Ducktail ribbed fender, 7 Metal West

Paint: Mopar F8 Green / Nissan Obsidian Black / Ford Graphite Metallic

Seat: Satin black powder-coated Accufast seat pan with single leaf spring suspension

Suspension/Front End:

Square lef girder with Honda Rebel shocks mounted behind legs to the lower rocker studs

Wheels/Tires/Brakes:

Front Wheel:  Satin black powder-coated SOHC CB750 rim laced to a CL450 dual leading shoe brake hub

Front Tire:  Shinko 705 110/80-19

Rear Wheel:  Satin black powder-coated DOHC CB750 rim laced to a late model CB750 drum hub

Rear Tire:  Shinko 705 130/90-19

Gauges/Info Center:

Vapor Computer System

     Speedometer, Tachometer, Trip/Odometer, Top Speed, Time, Head Temperature, Shift Lights/Redline Warning

Analog Oil Pressure Gauge

Lighting:

Headlight:  Cycle Standard 4.5 inch early style headlight with high beam indicator

Taillight:  Bullet style dual filament

Oil:

Capacity: 3.5 Quarts

Mobil 1 20w-50 Full Synthetic

Fuel:

Capacity: 3.7 Gallons

Premium 91+ Octane

Curb Weight:

450 Lbs

Cam Specs

Valve Lift

Duration

Int. Open

Int. Close

Exh. Open

Exh. Close

Lobe Center

Overlap

tappet Clearance

Sealed Duration

Int.

Exh.

Int.

Exh.

BTC

ABC

BBC

ATC

Int.

Exh.

Calculated

Int.

Exh.

Calculated

Megacycle 125-75

0.400

0.375

262 @.04

257 @.04

26

56

53

24

105

104.5

50

0.005

0.005

251

Rewelding and cleaning up some of the parts on Rock Flute

So I found out my kickstand can't take the entire weight of the bike dropping down on it. 450 lbs bent the tab enough for me to have to reweld it. While I had the welder out, I also added a bit of metal to the headlight mount because it had a tendency to vibrate at high speed. Both problems fixed and covered with a half assed attempt to blend satin black paint.

Wrap up with some ginger beer

Carburetor Return Springs

Brought to you by you local hardware store.