Common Honda GL1000 Carburetor Rebuilding Mistakes
You might consider this item: Randakk’s GL1000 Carb Rebuild Video
Here’s a partial list of problems encountered by amateurs when rebuilding GL1000 carbs. Often, I’m called upon to resolve botched rebuilds by incompetent mechanics, current or previous owners, brothers-in-law, and neighbors. Avoid these mistakes if you tackle a rebuild yourself.
GL1000 Carbs Restored by Randakk Customer Jouko Tomminen of of Lahti, Finland
Not so “Green,” No-Drop Idle Mixture Adjustment Method
I find the factory recommended idle mixture screw setting specs to be very close to ideal. They are listed here for the Honda GL1000.

Idle FUEL Mixture Screw on Honda GL1000
I do usually richen them up an extra 1/8 to 1/4 turn (out) to compensate for the leaner modern “gasoline” which is diluted with ethanol in most US markets.
But sometimes, you just need an excuse to do some high performance tuning on your bike! 🙂
One in a Million! Allan Zahrt’s Million Mile GL1000
How many million mile motorcycles are there? Answer below. Read on!
Allan Zahrt with his Million Mile GL1000!
In the early seventies Honda launched without fanfare an ambitious project. Internally, Honda had a bold plan: to build the world’s best motorcycle. Not just the best Japanese motorcycle – the best motorcycle available anywhere in the world. Period! The eventual result of this project was revealed to the world at the Cologne, Germany International Motorcycle Show (INTERMOT) in October, 1974 as the GL1000.
“Insensitive” Idle Mixture Fuel Screws?
“I’ve noticed that turning the idle mixture screws nets different results on each of the individual carbs on my Honda GL1000:
- #1 will kill the motor if turned all the way in
- #3 has NO EFFECT on engine speed regardless of where it is set
- #2 has what might be considered a “normal” effect
- #4 has only a very slight effect if any at all
What does this mean????? I’m a bit confused? Help please!!!!”
GL1000 Idle Mixture Fuel Screw
Fuel Filter Mounting Tips
Randakk’s High Performance Fuel Filters have many technical advantages and are super easy to install as demonstrated in this short video by by Shasta Smith – the Vintage Monkey.
More details on Randakk’s High Performance Fuel Filters here.
Honda GL1000 Coil and Spark Plug Cap Testing + Replacement Options
Coils are fabulously simple devices that work reliably and can last for decades with virtually no maintenance. I like to think of them as electricity “amplifiers.” When the breaker points open, the magnetic field produced by the primary windings collapses. Through the magic of induction, this collapse creates an energy force within the secondary windings of the coil. Since the number of windings is much greater on the secondary side, nominal battery voltage (roughly 12V) is multiplied to an incredible 8,000+ volts! This energy immediately finds a path to ground via the spark plugs…arcing helpfully in the process. Voila – we have ignition!
How to Cure Off-Idle Flat Spot “Glitch” in Honda GL1000
You might consider this item: Randakk’s GL1000 Carb Rebuild Video
Allow me a little soapbox time. Early GL1000s are routinely criticized for having poor carburetion. The criticism has been repeated so often by so many that it has become accepted as fact. Here is my contrarian view: the early GL1000s have great carburetion set-ups! My personal ’76 GL1000 show bike has flawless, near-linear carburetion…rheostat-like throttle response, no flat spots, starts easily, warms up fast enough and has a decent idle. My carbs are completely stock except for a few minor tweaks I make on all the carbs I service. I’ve owned and ridden many bikes. I believe the stock set-up on a GL1000, properly maintained and tuned delivers results as good as you can reasonably expect on a 4 cylinder, 4 carb bike of this vintage with this level of performance. In fact, GL1000 carburetion is easy to sort compared to some of the demonic setups I’ve encountered (my Weber-equipped Ducati 750 Nuevo Sport wins the prize as the worst I’ve ever personally grappled with).
General Honda GL1000 Troubleshooting Guide
You might consider this item: Randakk’s GL1000 Carb Rebuild Video
Note: You should do a valve adjust and compression test (in that order!) before doing ANY ignition or carb tuning. GL1000s will run poorly when valve lash is not set exactly to spec. Fortunately, valve lash stays “in spec” for a long time once properly set.
Honda GL1000 Carb Repair Kits Compared (Updated)
Note: an objective analysis of available Honda GL1000 carb kits was recently completed by Ron Carmichael.
Honda GL1000 CV Carb Cap “Button” Replacements
A new offering at Pistol Pete’s Services: newly developed OE style vacuum cap buttons replacements.
Honda GL1000 CV Carb Cap “Button” Replacements