Revision as of 02:31, 29 January 2018

1 Intake Manifold
2 Air Filter
3 LHD Fitment
4 Heat Shield
5 Adjustment
6 Linkage

Intake Manifold

Weber DCOE, Dellorto DHLA and Mikuni/Solex PHH use the same manifolds. Single or Twin manifolds are available, for round-port or oval-port A-series engines.

See main article: Intake Manifold

Single Dellorto DHLA
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Air Filter

Many use simple screens over the carburetor, which keep large objects out of the engine. This or no screen provides the fullest "awesome sidedraft sound", but at the expense of increased engine wear.

For filtering, the easiest thing is sock filters, but all sorts of regular and remote filter can be used.

See main article: Sidedraft Air Filters

LHD Fitment

Space for twin sidedrafts on LHD 1200s is limited because the brake master cylinder is on the carburetor side of the engine.

 See main article: LHD Sidedrafts

Heat Shield

Carb heat plate

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キャブヒートプレート

Adjustment

Idle Speed and Mixture Adjustment

Warm engine fully
Adjust curb idle speed to 900 rpm
Slowly turn mixture screw out until the engine speeds up, then keep turning out until engine starts to slow down slightly (overly rich)
Screw in (clockwise) until engine slows down (lean). Turn back out til it runs fastest (Best Lean)
Repeat for second barrel of the carburetor
If a twin-carb setup, repeat for the second carburetor

To get a 'feel' for this adjustment, turn the screw by half turns clockwise and anticlockwise till you hear the engine speed up and slow down. Then fine turn with 1/4 turns. Do this repeatedly until you are confident of the results.

Linkage

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Linkage depends in part on the manifold you use. Does it have bolt-bosses for linkage? Or does it have built-in linkage bar?

Side Pull

Tomei manifold Side Pull. Nismo/Tomei manifold have built-in bar towers and use a large diameter cross bar
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Center Pull

Center Pull - Need the floating lever for the carburetors. In essence, a single throttle lever, with its own balance screw

Center Pull needs only one carb-pull, eliminating the separate throttle adjustments. The center floating linka has its own balance screw
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