Can't Gain RPM

mishcmat · July 18th, 2017, 08:43 PM

Been searching endlessly on the forum trying to figure this issue out. It's a 2009 250r 12k on it. Did the $36 muffler, months ago, 2 washer shim over weekend to take care of the flat spot at 9k-11k rpm.

Bike ran great, started well ran like a raped ape. Took to work, back home no issues. Went of an evening ride, ran great for about 1.5 miles, and now it has very little power.

Still idles fine, starts fine, it is slower to rev at idle but not really noticeable unless you're looking for it. Checked the intake took out the air filter nothing plugged.

It seems go ok with very little to no throttle, and severely bogs when opened up. I could only get home going up hill in 2nd @ 6krpm at 25mph.

Cracked the tank incase it's vacuum locked and no change.

I've read carb issues, vacuum issues, fuel filter/line issues, ignition issues, but have no idea where to start, since it was so all of a sudden.

Any help is appreciated.

maverick9611 · July 18th, 2017, 09:27 PM

Quote:

Originally Posted by mishcmat

Been searching endlessly on the forum trying to figure this issue out. It's a 2009 250r 12k on it. Did the $36 muffler, months ago, 2 washer shim over weekend to take care of the flat spot at 9k-11k rpm.

Bike ran great, started well ran like a raped ape. Took to work, back home no issues. Went of an evening ride, ran great for about 1.5 miles, and now it has very little power.

Still idles fine, starts fine, it is slower to rev at idle but not really noticeable unless you're looking for it. Checked the intake took out the air filter nothing plugged.

It seems go ok with very little to no throttle, and severely bogs when opened up. I could only get home going up hill in 2nd @ 6krpm at 25mph.

Cracked the tank incase it's vacuum locked and no change.

I've read carb issues, vacuum issues, fuel filter/line issues, ignition issues, but have no idea where to start, since it was so all of a sudden.

Any help is appreciated.

i went from stock 98's to 100's on main jet when i switched to my ali elcheapo slip on. i had to to go 3 washers on needles. could be spark/coil, valves, clogged fuel filter, intake/airbox boots. i'm sure others will chime in

Triple Jim · July 18th, 2017, 09:28 PM

Maybe one cylinder not firing for some reason?

mishcmat · July 18th, 2017, 10:17 PM

Quote:

Originally Posted by Triple Jim

Maybe one cylinder not firing for some reason?

I'm leaning this waybut not sure. I'm going to take it to work tomorrow and see if it does it still. Something tells me it'll run cold.

Ghostt · July 18th, 2017, 10:48 PM

You might want to double check those slides diaphragms again, maybe you pinched one?. Or they didn't get seated correctly when you did the washers.

I'm not familiar with NewGen, do they use the spark plug caps as PreGen? If so you might want to service those as well, and while your at it renew the HT leads.

ducatiman · July 19th, 2017, 05:36 AM

I'd take the time to review all previous work...assembly error? Something left a bit loose?

Def check slide rubbers for pinch, too. Some fit perfect, but if either swollen or contracted..they can be a very tricky install. There is no definitive rule here, fit (swollen/shrunken) can actually be mixed between carbsets...great care always
necessary when both removing and installing. Frankly, very easy to err.

Some stuff to check, at least.

jkv45 · July 19th, 2017, 06:26 AM

I agree - I think you need to look for a reason the slides are not lifting properly like a torn or misaligned diaphragm.

Check simple stuff like plug boots too, and make sure the gas is fresh, but chances are something is not right in one of the carbs.

mishcmat · July 19th, 2017, 08:25 AM

Quote:

Originally Posted by jkv45

I agree - I think you need to look for a reason the slides are not lifting properly like a torn or misaligned diaphragm.

Check simple stuff like plug boots too, and make sure the gas is fresh, but chances are something is not right in one of the carbs.

My hunch was wrong, still happening today.

Guess into the carbs I go. Is there any definitive way of checking to make sure the slides are moving up and down? I only did 1 carb at a time so at least I can rule out mixing parts up between the two.

ducatiman · July 19th, 2017, 08:41 AM

opening and doing a "visual" first is suggested. Look for proper seating, tears, pinches along the edges. Verify jets, emulsion tubes, anything else you disturbed are all tight and accounted for. Are the needle jets present and assembled correctly? UNDER the emulsion tubes?

Test slide lift? Yes can be done..., very controlled, deliberate blast of compressed air into the circled area of my attached pic should raise ...suggest to keep blowgun about 12-16 inch away until you become accustomed to the slide reaction...the goal is simply to guage reaction, NOT destroy them. ****Easy does it*****

Now, to find that picture....these are EX500 carbs, but same applies. My "paint" skills horrible, but the upper ports are the target.

jkv45 · July 19th, 2017, 08:41 AM

Quote:

Originally Posted by mishcmat

My hunch was wrong, still happening today.

Guess into the carbs I go. Is there any definitive way of checking to make sure the slides are moving up and down? I only did 1 carb at a time so at least I can rule out mixing parts up between the two.

You may be able to reach in the airbox and manually lift the slides to see if they move freely and drop at the same rate - but I'm not sure that's a conclusive test of anything unless they don't.

You can also check the temp of the pipes with a IR temp gun to determine which side has the issue.

mishcmat · July 19th, 2017, 09:38 AM

I might see if I can move the slides up and down. Maybe a piece of dirt got it and lodged a slide. I did do the work on the lazy side, without removing the carbs. Who knows if something got in. I felt it was clean, diaphragms looked good and seated well, but who knows. It's just so odd that it ran so good, then like flicking a switch not so good.

mishcmat · July 19th, 2017, 08:07 PM

Fixed. Embarrassed to say that it was the fuel shut off. It never worked since I bought the bike and was always on. Apparently it decided to start working and just happened to be in the off position.

Triple Jim · July 19th, 2017, 08:40 PM

Ha, I had a fuel filter get clogged a couple months ago. It's amazing how poorly an engine runs when it doesn't get any gasoline.

CaliGrrl · July 19th, 2017, 10:13 PM

Glad you figured it out! Running out of gas will do that, too. Good idea to practice switching to "reserve" on the fly. Make sure you can, if you need to. I had to stop, since I didn't get to it before the bike died, move the switch, and restart the bike.

Ghostt · July 20th, 2017, 06:55 AM

Quote:

Originally Posted by mishcmat

Fixed. Embarrassed to say that it was the fuel shut off. It never worked since I bought the bike and was always on. Apparently it decided to start working and just happened to be in the off position.

KikRox · July 22nd, 2017, 09:00 AM

Quote:

Originally Posted by Triple Jim

Ha, I had a fuel filter get clogged a couple months ago. It's amazing how poorly an engine runs when it doesn't get any gasoline.

LOL amen to that... the story of my summer!! Been dumping gas, cleaning carbs and the tank repeatedly this year... the little 250 is already a gutless powerplant in terms of torque and horsepower so every little bit of fuel counts. I will be out rocking down the highway and then my tank (which doesnt always like to vent right) will decide to gag my fuel system then its *rattle rattle rattle bog bog bog*

July 18th, 2017, 08:43 PM	#1
mishcmat ninjette.org newbie Name: Me Location: BC Join Date: Jun 2017 Motorcycle(s): Ninja 250 Posts: 5	Can't Gain RPM Been searching endlessly on the forum trying to figure this issue out. It's a 2009 250r 12k on it. Did the $36 muffler, months ago, 2 washer shim over weekend to take care of the flat spot at 9k-11k rpm. Bike ran great, started well ran like a raped ape. Took to work, back home no issues. Went of an evening ride, ran great for about 1.5 miles, and now it has very little power. Still idles fine, starts fine, it is slower to rev at idle but not really noticeable unless you're looking for it. Checked the intake took out the air filter nothing plugged. It seems go ok with very little to no throttle, and severely bogs when opened up. I could only get home going up hill in 2nd @ 6krpm at 25mph. Cracked the tank incase it's vacuum locked and no change. I've read carb issues, vacuum issues, fuel filter/line issues, ignition issues, but have no idea where to start, since it was so all of a sudden. Any help is appreciated.

July 18th, 2017, 10:48 PM	#5
Ghostt in your machine Name: Scott Location: Summer Shade, Ky. Join Date: Oct 2014 Motorcycle(s): 98 Ninja 250/F12 aka ZX-2R "SERENITY", 91 Ninja 500/A5 aka ZX-5R "Phoenix", 84 Honda GL1200A "SIREN" Posts: A lot. Blog Entries: 25 MOTM - Jun '17, May '16, Mar '15	You might want to double check those slides diaphragms again, maybe you pinched one?. Or they didn't get seated correctly when you did the washers. I'm not familiar with NewGen, do they use the spark plug caps as PreGen? If so you might want to service those as well, and while your at it renew the HT leads. __________________________________________________ *violente et ignorantia* ZX-2R BLOG *Twitter and Instagram = Ghostt_Scott* *I'm not here to change your mind, just to inform.*
	1 out of 1 members found this post helpful.

July 19th, 2017, 05:36 AM	#6
ducatiman ninjette.org certified postwhore Name: Gordon Location: new york Join Date: Sep 2009 Motorcycle(s): '95 DUCATI 900SS/SP '07 DUCATI SS800 '19 HONDA CBR650R Posts: A lot. MOTM - Nov '18, Mar '17	I'd take the time to review all previous work...assembly error? Something left a bit loose? Def check slide rubbers for pinch, too. Some fit perfect, but if either swollen or contracted..they can be a very tricky install. There is no definitive rule here, fit (swollen/shrunken) can actually be mixed between carbsets...great care always necessary when both removing and installing. Frankly, very easy to err. Some stuff to check, at least. __________________________________________________ gordon@customcarbservices.com Custom Carb Service www.customcarbservices.com
	1 out of 1 members found this post helpful.

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July 18th, 2017, 09:28 PM	#3
Triple Jim Guy Who Enjoys Riding Name: Jim Location: North Carolina Join Date: Jul 2016 Motorcycle(s): Ninja 250 Posts: A lot. MOTM - Oct '18, Aug '17, Aug '16	Maybe one cylinder not firing for some reason?

July 19th, 2017, 06:26 AM	#7
jkv45 Rev Limiter Name: Jay Location: WI Join Date: Jul 2013 Motorcycle(s): '06 SV650n, '00 Derbi GPR, '64 CA77 Dream 305, '70 CL450 Scrambler, numerous dirt bikes Posts: A lot. MOTM - Jun '18, Oct '16	I agree - I think you need to look for a reason the slides are not lifting properly like a torn or misaligned diaphragm. Check simple stuff like plug boots too, and make sure the gas is fresh, but chances are something is not right in one of the carbs.

July 19th, 2017, 09:38 AM	#11
mishcmat ninjette.org newbie Name: Me Location: BC Join Date: Jun 2017 Motorcycle(s): Ninja 250 Posts: 5	I might see if I can move the slides up and down. Maybe a piece of dirt got it and lodged a slide. I did do the work on the lazy side, without removing the carbs. Who knows if something got in. I felt it was clean, diaphragms looked good and seated well, but who knows. It's just so odd that it ran so good, then like flicking a switch not so good.

July 19th, 2017, 08:07 PM	#12
mishcmat ninjette.org newbie Name: Me Location: BC Join Date: Jun 2017 Motorcycle(s): Ninja 250 Posts: 5	Fixed. Embarrassed to say that it was the fuel shut off. It never worked since I bought the bike and was always on. Apparently it decided to start working and just happened to be in the off position.

July 19th, 2017, 08:40 PM	#13
Triple Jim Guy Who Enjoys Riding Name: Jim Location: North Carolina Join Date: Jul 2016 Motorcycle(s): Ninja 250 Posts: A lot. MOTM - Oct '18, Aug '17, Aug '16	Ha, I had a fuel filter get clogged a couple months ago. It's amazing how poorly an engine runs when it doesn't get any gasoline.

July 19th, 2017, 10:13 PM	#14
CaliGrrl ninjette.org certified postwhore Name: Kerry Location: Ventura, CA Join Date: Jan 2016 Motorcycle(s): Ninja650 Posts: A lot. MOTM - Apr '18, Apr '17, Apr '16	Glad you figured it out! Running out of gas will do that, too. Good idea to practice switching to "reserve" on the fly. Make sure you can, if you need to. I had to stop, since I didn't get to it before the bike died, move the switch, and restart the bike.