Return to main Tech Tips Index

GL1000 CV Slide / Cap Variations

This material is covered in my GL1000 Carb Rebuild Video, but just in case you haven't made that great investment...

• Repair with epoxy (clear looks best and can be buffed to achieve a nearly original looking sheen). Do this off the bike and take care not to block the tiny vacuum transfer port in the cap.
• Replace with used cap and CV slide. These are matched pairs...machined to a very tight tolerance and weight matched by the factory...never mix and match slides and caps.
• New OEM cap/slide/needle assembly...very spendy.

All GL1000 carb caps caps are functionally equivalent (except for clearance matching). Caps and CV slides are matched pairs machined to a very tight tolerance and weight matched by the factory. They should never be interchanged.

There are actually 3 types of CV slides fitted to the 5 years of production on GL1000s. These are shown in the pictures below. Never interchange CV slide types as this will affect cylinder balance and introduce tuning problems!

'75 models have a "scalloped" cut-out on bottom surface of CV slide (note brass insert)

'75 design design permits slightly better flow at wide open throttle

'76 - '77 models have a CV slide with flat bottom*

* Some '76 -'77 CV slides have brass inserts and some do not. They are functionally equivalent.

'78-'79 models have a CV slide with radiused bottom edge + Keihin reverted to brass inserts

More on the issue of fit...

The close tolerances are especially critical in the CV slide center "piston" to cap "bore" aspect. This area is the source of most CV slide binding and sticking and this is where your cleaning / polishing efforts should be concentrated. The clearance between the outer wall of the cap and the CV skirt is much greater. However, most amateur mechanics erroneously focus their cleaning / polishing efforts there.

Blue arrows in the picture above show where you should focus your cleaning / polishing efforts

Take care to keep small relief port (yellow arrow) clear

Note to Restorers Regarding "Correct" Cap Orientation

Carb caps can be mounted in one of two different orientations with respect to the Keihin logos. Either way is fine. They are functionally equivalent.

Hard evidence is somewhat conflicting, but the consensus of opinion for "correct" restorations (and my practice) is to mount the caps so that the cap logos are right side up on the left carbs (carbs #2 and #4) and upside down on the right carbs (carbs #1 and #3)...as viewed by the rider in riding position.

Return to main Tech Tips Index

Intellectual Property Notice: All material appearing in this website is the property of Randall Washington, and is protected under United States and international copyright laws. The photographs, text and other content may not be copied, reproduced, distributed, stored, or manipulated in any manner without the express written permission of Randall Washington.

For more information on the use of material from this website, click here

^top^