GMan Suzuki Carburetor Tuning Info for VL1500

GMan's Motorcycle Carburetor Blog
Specifically for the Suzuki Intruder VL1500
(Viable for almost any carbureted bike)

My Carb Tuning started in the 1960's when everything was carbed
and Fuel Injection was primitive and only for a handful of sport cars..
(For EFI info I have another blog, EFI Tuning for Motorcycles Made Simple)

Carburetors, those scary, complex aluminum boxes that once cracked open are like Humpty-Dumpty and can never be put back together again.

Let me prove that above statement wrong by addressing carb tuning and rejetting for maximum performance and mileage.
I'll make sure to steer clear of Bernoulli's Principle with it's 
scientific talk of static vs dynamic pressures, etc.
Being a hands on, self taught 'Carb Tuner', I back up my seat-of-the-pants tuning with dyno runs, charts and proven results. 

There are currently thousands of carbs in everyday service on Suzuki Intruder VL1500's all over the world that I have personally setup for maximum performance and mileage and still counting.

GMan Industries / CarbWorks Division
The following details what and why my Setups work so well!

Motorcycle Carburetors 101 - Common Myths and Misunderstandings:

?Will changing Intake to a free flowing cleanable Air Filter increase performance?
Simply opening the intake creates an imbalance that needs to be fixed. Performance does not increase only unless the carb is properly rejetted at the same time. If not the only advantage is a cleanable air filter with a leaner, hotter running motor with decreased performance, longevity and mileage. Carbs mix the air with fuel. Changing the intake changes the air supplied requiring jetting changes to keep the fuel to air ratio at it's optimum.  Will motorcycles run properly without rejetting as noted? Some, depending on how free flowing the stock intake and air filter are along with elevation and certain climate conditions. Most....NO!

?Does changing the Exhaust from stock to Aftermarket increase performance?
Changing exhaust pipes from stock to aftermarket can usually take place without re-tuning the bike, but re-tuning is always recommended. Why? To get the most value from the new exhaust. Changing to aftermarket exhaust makes the motorcycle louder and sound more powerful, but rarely increase performance by itself. Usually torque is reduced, some popping occurs, but the bike will weigh less and 'feel' powerful. To get the most benefit from aftermarket exhaust carb changes will be required, even if just minimally. Why? Reducing restrictions to the exhaust flow changes combustion which changes intake slightly thus requiring jetting revisions.

?Changing Exhaust to a more free flowing system increases performance?

Q: What makes the Bully better than other EFI Controllers?
A: GMan's Bully EFI Controller puts you in control of yours settings and state of tune. You can tweak/change them at anytime, anyplace, even while you ride for immediate results. Other controllers do not have this ability and usually require downloads, maps, tech's with special tools, etc. Ever pay for a dyno tune and she still has issues with popping, hiccups, bad fuel mileage, etc? Have you had to 'live with it.' That is no longer necessary with our Bully EFI Controller as it comes preset to your motor and your after market exhaust and a custom intake. If you feel it needs adjusting, YOU can do so while you ride for instant results. Not perfect yet, change your adjustment slightly and continue to ride until she is exactly what you want. No Dyno Runs, Down Time, Unsatisfactory results. If you get confused simply return settings back as they were. 90%+ of the time the preset settings are the best for your setup, it's so simple to tweak that most end up tinkering to see how it affects the ride, but end up at the preset settings when done.......there's a reason for that!We know bikes and tuning and ride with everything we offer, making sure it performs as expected.

Q: What are the various Stages I here about and what makes each one different?
A: Stages are variations in your setup for added performance. The higher the Stage number the more aggressive the setup and usually the greater the performance. There is no universally sanctioned definition for what constitutes each stage, but the more commonly accepted definitions are as follows:
Stage 1 - Standard Intake(Stock) mated to after market exhaust. Results, minimal performance increase.
Stage 2 - Open/Free Breathing Intake with Stock Exhaust. Results, increased performance with higher rpm limits.
Stage 3 - Open/Free Intake mated to after market exhaust. Results in much increased performance depending on design of exhaust, flow of intake and A/F Ratio adjustments throughout the rpm range.

The following Stages are GMan Slang are not universally known, but added due to results from GMan Performance Exhaust design and testing.

Stage 3.5 - As Noted for Stage 3 above, but specifically as it relates to the addition of GMan Exhaust on the Suzuki VL1500 Carbed and FI Versions

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