Inspection

17 Check the operation of the choke plunger. If it doesn't move smoothly, inspect the plunger assembly and linkage components and renew any that are worn, damaged or bent (see illustration).

	I^mL	In
I		-**►' *
			■

7.13c Note how return spring locates on 7.13d Remove linkage bar collars ...

bar

7.13e ... and return spring

_©

_©

7.14a Unscrew choke plunger nut...

7.14b . .. and withdraw spring (A) and plunger (B)

7.17 Choke plunger spring (A), choke plunger (B) and plunger nut (C)

4*8 Fuel and exhaust systems

7.18 Check the tapered portion of the pilot screw (arrowed) for wear

18. If removed from the carburettor, check the tapered portion of the pilot screw and the spring for wear or damage (see illustration). Renew them if necessary.

19. Check the carburettor body, float chamber and top cover for cracks, distorted sealing surfaces and other damage (see illustration). If any defects are found, renew the faulty component, although renewal of the

7.19 Inspect the carburettor body for wear and damage

entire carburettor will probably be necessary (check with a Honda dealer on the availability of separate components).

20. Check the piston diaphragm for splits, holes and general deterioration (see illustration). Holding it up to a light will help to reveal problems of this nature.

21. Insert the piston in the carburettor body and check that the piston moves up-and-

7.20 Carburettor components - Top cover and retaining screws (a), piston spring (b), jet needle holder and spring (c), jet needle and washer (d), piston (e) and diaphragm (f)

down smoothly. Check the surface of the piston for wear. If it's worn excessively or doesn't move smoothly in the guide, renew the components as necessary.

22. Check the jet needle for straightness by rolling it on a flat surface such as a piece of glass. Renew it if it's bent or if the tip is worn.

23. Check the tip of the float valve and the valve seat. If either has grooves or scratches in it, or is in any way worn, they must be renewed as a set. Gently push down on the rod on the top of the valve then release it - if it doesn't spring back, renew the valve (see illustration 7.8b).

24. Check the float for damage. This will usually be apparent by the presence ot fuel inside the float. If the float is damaged, it must be renewed.

25. Operate the throttle shaft to make sure the throttle butterfly valve opens and closes smoothly. If it doesn't, cleaning the throttle linkage may help. Otherwise, renew the carburettor (see illustration).

26. Clean the threads of the synchronising screw with solvent and a brush without disturbing the screw. When dry, lightly grease the screw threads (see illustration).

_I

Carburettors - reassembly and float height check

A Warning: Refer to the precautions given in Section 1 before proceeding. Note: When reassembling the carburettors, be sure to use new O-rings and gaskets. Do not overtighten the carburettor jets and screws as they are easily damaged.

1. If removed, install the choke plunger assemblies into the carburettor bodies.

2. Fit the choke return spring to the left-hand carburettor. Fit the choke linkage bar collars, then locate the bar, making sure the arms fit onto the plungers, and fit the plastic washers and secure the bar with the screws (see illustration).

3. Locate the cranked end of the spring in the notch on the bar (see illustration 7.13c).