engine boggs down while accelerating

gemini · 10-16-2014, 01:43 PM

I have a 2006 GZ250 with 8,000 miles. I just had it tuned up less than a month ago. I was riding home from work the other day, everything was fine, then I stop at a red light. When I accelerated the engine bogged down. I got out of the throttle and it idled fine. I tried to accelerate and it would lose power again. I coasted into a parking lot. I shut off the bike and it started right back up no problem. The bike idled fine but I could not give it much throttle without it bogging down. I left the bike for a couple of hours till traffic slowed down. I went back and it started up just fine and was idling normal but still it would fall on it's face when I tried to give it throttle. I put it in 1st gear and was able to idle around the parking lot fine. I was able to shift into 2nd gear and could give it just a little throttle before it would lose power again. I finally was able to ride the two blocks home but if I gave it throttle and held it open the bike would bog down for a second then it would surge back to power for a second then bog down again. It jerked up and down all the way home as long as I was trying to accelerate. I started it the next day and it did the same thing. I rode it around the parking load I could ride in 1st giving it just a little throttle before started bogging down again. I have tried riding it a couple of time now and it runs fine as long as I only give it a little throttle. I can keep speed and shift up to 2 and 3rd gear giving it a little gas. Once I get to a certain point it starts jerking again. Any Ideal what is causing this.

**jonathan180iq** · 10-16-2014, 02:49 PM

You have a large vacuum leak, or air leak, somewhere in the intake.

Check the "S" tube that runs from the bottom of the airbox to the crankcase. It's on the left side (passenger side US)

If that's not it, check the coupler boots on both sides of the carb, leading into the card from the air box, and then leading form the carb to the head.

What you're describing is too pronounced to be a simple vacuum line coming undone - but if you don't find it in the places I mentioned, then check those. There are 3 of them, connecting the bottom of the tank to the carb body.

raul10141964 · 10-16-2014, 02:54 PM

check for dirt on the main jet

tnastvogel · 10-19-2014, 12:20 AM

bad/clogged pilot jet? or maybe a bad vacuum diaphragm? take apart your carb and inspect/clean it.

gz4me + · 10-19-2014, 05:52 AM

What does the air cleaner look like? When was the last time it was changed or cleaned? The neighbor next door had same problem on his honda scooter. The scooter would start and idle fine. As soon as he gave it gas, it would stall. When he changed air cleaner, scooter ran fine.

raul10141964 · 10-19-2014, 11:24 AM

pilot jet affect the idle, main jet affect from 1/4 to full throttle but mot the idle.
clean the carb and install an inline fuel filter

Water Warrior 2 · 10-19-2014, 03:16 PM

Oh yeah, do install an inline fuel filter. A little prevention is worth a lot of time saved later on down the road.
Also do not buy cheap gas. Stick with top tier suppliers. You still only need 87 octane but stay away from discount gas suppliers who may have lower production standards.
I suffered from computer codes popping up on my Vstrom until I switched back to Chevron. Wisdom is gained through experience and bad decisions.

10-16-2014, 01:43 PM	#1
gemini Junior Member Join Date: Oct 2014 Posts: 1	engine boggs down while accelerating I have a 2006 GZ250 with 8,000 miles. I just had it tuned up less than a month ago. I was riding home from work the other day, everything was fine, then I stop at a red light. When I accelerated the engine bogged down. I got out of the throttle and it idled fine. I tried to accelerate and it would lose power again. I coasted into a parking lot. I shut off the bike and it started right back up no problem. The bike idled fine but I could not give it much throttle without it bogging down. I left the bike for a couple of hours till traffic slowed down. I went back and it started up just fine and was idling normal but still it would fall on it's face when I tried to give it throttle. I put it in 1st gear and was able to idle around the parking lot fine. I was able to shift into 2nd gear and could give it just a little throttle before it would lose power again. I finally was able to ride the two blocks home but if I gave it throttle and held it open the bike would bog down for a second then it would surge back to power for a second then bog down again. It jerked up and down all the way home as long as I was trying to accelerate. I started it the next day and it did the same thing. I rode it around the parking load I could ride in 1st giving it just a little throttle before started bogging down again. I have tried riding it a couple of time now and it runs fine as long as I only give it a little throttle. I can keep speed and shift up to 2 and 3rd gear giving it a little gas. Once I get to a certain point it starts jerking again. Any Ideal what is causing this. Login or Register to Remove Ads
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10-16-2014, 02:54 PM	#3
raul10141964 Senior Member Join Date: Apr 2012 Location: Elkhart, Indiana Posts: 369	check for dirt on the main jet Login or Register to Remove Ads
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10-19-2014, 05:52 AM	#5
gz4me + Senior Member Join Date: Sep 2013 Location: Santa Maria, California Posts: 234	What does the air cleaner look like? When was the last time it was changed or cleaned? The neighbor next door had same problem on his honda scooter. The scooter would start and idle fine. As soon as he gave it gas, it would stall. When he changed air cleaner, scooter ran fine. Login or Register to Remove Ads Last edited by gz4me +; 10-19-2014 at 06:04 AM.
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10-16-2014, 02:49 PM	#2
jonathan180iq Super Moderator Join Date: Jan 2007 Location: Dalton, GA Posts: 3,996	You have a large vacuum leak, or air leak, somewhere in the intake. Check the "S" tube that runs from the bottom of the airbox to the crankcase. It's on the left side (passenger side US) If that's not it, check the coupler boots on both sides of the carb, leading into the card from the air box, and then leading form the carb to the head. What you're describing is too pronounced to be a simple vacuum line coming undone - but if you don't find it in the places I mentioned, then check those. There are 3 of them, connecting the bottom of the tank to the carb body.
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10-19-2014, 12:20 AM	#4
tnastvogel Junior Member Join Date: May 2014 Posts: 24	bad/clogged pilot jet? or maybe a bad vacuum diaphragm? take apart your carb and inspect/clean it.
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10-19-2014, 11:24 AM	#6
raul10141964 Senior Member Join Date: Apr 2012 Location: Elkhart, Indiana Posts: 369	pilot jet affect the idle, main jet affect from 1/4 to full throttle but mot the idle. clean the carb and install an inline fuel filter
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10-19-2014, 03:16 PM	#7
Water Warrior 2 Senior Member Join Date: Dec 2006 Location: Squamish B.C Canada Posts: 11,409	Oh yeah, do install an inline fuel filter. A little prevention is worth a lot of time saved later on down the road. Also do not buy cheap gas. Stick with top tier suppliers. You still only need 87 octane but stay away from discount gas suppliers who may have lower production standards. I suffered from computer codes popping up on my Vstrom until I switched back to Chevron. Wisdom is gained through experience and bad decisions.
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