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HSR42/45/48 Carburetors
(General Tuning Procedures)
Air Filter Service Instructions
A. Pre Cleaning:
Tap the element to dislodge any large embedded
dirt, then gently brush with a soft bristle brush.
B. Pan Cleaning:
Soak or roll element in a large shallow pan of
K&N air ilter cleaner (1/4 the depth of 1 pleat). Remove
immediately and let sit for approximately 10 minutes.
C. Rinse off:
Rinse off the element with low pressure water, tap
water is OK. Always lush from the inside of the ilter out. This
removes the dirt and does not drive into the ilter.
IMPORTANT:
Air dry only.
D. Oiling:
After the ilter has dried always re-oil before using.
Apply K&N air ilter oil with ones pass per pleat. Wait 10
minutes and re-oil any white spots still showing. IMPORTANT:
Do not use gasoline or cleaning solvent to service the ilter
element as this will damage the ilter.
Overlow
1.
Worn needle valve or dirty valve seat.
2
. Improper fuel level in loat bowl.
3
. Damaged loat bowl O-ring gasket.
4.
Loose loat bowl screws.
5.
Pressurized fuel tank.
6.
Broken needle valve O-ring.
Poor Idling
1.
Fuel iller cap not venting.
2.
Idle speed improperly adjusted.
3.
Clogged bypass or outlet.
4
. Clogged pilot jet.
5.
Loose pilot jet.
6.
Air leak in system.
7.
Choke not fully closed.
8.
Crank vent blocked.
Poor Fuel Economy
1.
Filler cap not venting.
2.
Fuel level too high (overlows).
3.
Loose jets.
4.
Choke not fully closed.
5.
Dirty air cleaner.
Poor Acceleration
1.
Clogged accelerator system.
2.
Clogged pilot jet.
3.
Fuel level too low.
Hard Starting
1.
Choke not operating properly.
2.
Generally dirt carburetor.
3.
Air leak in system.
4.
Excessive use of throttle before
starting engine.
Poor Performance on the Road
1.
Fuel iller cap not venting.
2.
Fuel level incorrect.
3.
Main jet loose.
4.
Air leak in system.
5.
Generally dirty carburetor.
6.
Dirty air ilter.
Poor High Speed Performance
1.
Fuel iller cap not venting.
2.
Loose man jet.
3.
Incorrect Fuel level
4.
Strainer in fuel tank dirty.
5.
Clogged main jet.
Check for: Remedy:
1.
Replace or clean
2
. Adjust level.
3
. Replace O-ring.
4.
Tighten screws.
5.
Check for proper fuel tank venting.
6.
Replace O-ring.
1.
Replace iller cap
2.
Adjust idle speed.
3.
Clean carburetor.
4
. Clean jet.
5.
Tighten jet.
6.
Tighten manifold or hose clamps.
7.
Adjust cable.
8.
Remove blockage from hose or
passage.
1.
Replace iller cap
2.
Adjust level.
3.
Tighten jets.
4.
Adjust cable.
5.
Clean or replace
1.
Clean.
2.
Clean.
3.
Adjust level.
1.
Adjust cable.
2.
Clean
3.
Tighten manifold or hose clamps.
4.
Do not open throttle before starting.
1.
Replace iller cap.
2.
Adjust level.
3.
Tighten Jet.
4.
Tighten manifold or hose clamps.
5.
Clean
6.
Clean or replace
1.
Replace iller cap.
2.
Tighten jet.
3.
Adjust level.
4.
Clean.
5.
Clean.
A. Invert the carburetor and remove the loat bowl.
B. The loat assembly’s actuator tab should just begin contact
with the Needle Valve assembly when the bottom if the loat is
18mm from the carburetor bottom surface as shown.
C. If adjustment is required, adjust by bending the actuator tab.
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