Author Topic: no acceleration past 1/3 throttle  (Read 1079 times)

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Offline gskoz

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no acceleration past 1/3 throttle
« on: April 23, 2019, 03:17:36 PM »
I have a Suzuki gs550 with cb550 carbs that won't get up to speed. while riding, if I give it anymore than 1/3 throttle or attempt to accelerate quickly- the bike feels like it wants to quit running.

almost as if its not pulling from the main jets, is it a possibility that i'm running on the idle jets only? perhaps the float level should be set another height other than the stock cb550 settings.

I know I'm getting enough fuel to the carbs as I've tried two tank setups. Ignition seems fine, plugs are clean.

thank you







Offline Scott S

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Re: no acceleration past 1/3 throttle
« Reply #1 on: April 23, 2019, 04:40:48 PM »
 What year GS? Some years came with slides, some were CV carbs.
 Just because they are both 550cc doesn't mean the carbs will work. You're probably better off looking for stock GS550 carbs.
'71 CB500 K0
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Offline HondaMan

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Re: no acceleration past 1/3 throttle
« Reply #2 on: April 23, 2019, 06:25:26 PM »
I have a Suzuki gs550 with cb550 carbs that won't get up to speed. while riding, if I give it anymore than 1/3 throttle or attempt to accelerate quickly- the bike feels like it wants to quit running.

almost as if its not pulling from the main jets, is it a possibility that i'm running on the idle jets only? perhaps the float level should be set another height other than the stock cb550 settings.

I know I'm getting enough fuel to the carbs as I've tried two tank setups. Ignition seems fine, plugs are clean.

thank you

For the GS550 you will likely need to increase the mainjet size in those carbs. The CB550 has very long intake runners where the GS does not: the mainjet is being lifted (in the emulsifiers) by the air speed at the bell side of the slides, and with the short runners there is more turbulence in that area. You can try this test: when you reach the spot where it starts to stumble, partly close the choke to see how much it helps.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

ken65

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Re: no acceleration past 1/3 throttle
« Reply #3 on: April 23, 2019, 07:06:36 PM »
Wish I knew a 1/4 of what you know Hondaman.

Offline HondaMan

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Re: no acceleration past 1/3 throttle
« Reply #4 on: April 25, 2019, 06:09:38 PM »
Wish I knew a 1/4 of what you know Hondaman.

I wish I knew how to mind-meld it to these forums!
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com