ninjette.org

Go Back   ninjette.org > 1986 - 2007 Ninja 250R > 1986 - 2007 Ninja 250R Tech Talk

Reply
 
Thread Tools
Old September 10th, 2021, 04:23 PM   #41
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
#108 main jet Keihin. #35 pilot jet. Found a missing "D" ring inside the air cut valve that was probably causing the hanging idle, lean condition. So ordered a rebuild kit. Still will not rev up and also the 6 pin plug that plugs into the voltage regulator is getting really hot, so any help with these continuing issues would be greatly appreciated.

Thank you
Tom
tomsninja2020 is offline   Reply With Quote




Old September 10th, 2021, 04:41 PM   #42
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
When a connector is getting hot it means it's not making good electrical connections with the mating connector. Clean the pins and use something like DeoxIT on them. If necessary, squeeze the female contacts so they grip the male contacts better.
Triple Jim is offline   Reply With Quote


Old September 11th, 2021, 07:12 AM   #43
ducatiman
ninjette.org certified postwhore
 
ducatiman's Avatar
 
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
Quote:
Originally Posted by ducatiman View Post
"

I'll get back on the "oring' size (its actually a "D" ring, but a oring could be subbed)
PS.....a 1 x 4mm oring, squeezed in, seals fine
__________________________________________________
Gordon
Custom Carb Service

www.customcarbservices.com
ducatiman is offline   Reply With Quote


Old September 11th, 2021, 02:35 PM   #44
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Got it to run and It will free rev past 5000 rpm but slow to get there. Once it gets to 5,000 RPM it hesitates before going up any higher. should i shim the needles up one and see if that helps?

Tom
tomsninja2020 is offline   Reply With Quote


Old September 11th, 2021, 08:23 PM   #45
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Sure, you can shim needles to see if it improves or worsens stumble.

Although you really should confirm that slides are actually moving past mid-range to rule out vacuum issues.
DannoXYZ is offline   Reply With Quote


Old September 13th, 2021, 03:01 PM   #46
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Just a quick update. compression is around 95 to 100 psi on both cylinders but bike will run, battery not staying charged and the bike stops running due to a bad rectifier/regulator not supplying enough power to the battery, so ordered a new one. Got the carbs synced up pretty close.

I had put new rings in it last year and I am wondering if maybe they still are not seated correctly, both cylinders have been honed to achieve a nice cross-hatch pattern.

Noticed that it takes a lot of cranking from the starter to get it to start up. My friend has a 4 cylinder bike and it fire up as soon as he hits the starter button.

All help is greatly appreciated.
Thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 13th, 2021, 08:31 PM   #47
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by tomsninja2020 View Post
Noticed that it takes a lot of cranking from the starter to get it to start up. My friend has a 4 cylinder bike and it fire up as soon as he hits the starter button.
Is this with full-choke? No difference with & without choke? Then choke-passages in carbs aren't clean.

Darn, I think I may have spare RR to send you with bars & foot-peg... let me check...
DannoXYZ is offline   Reply With Quote


Old September 15th, 2021, 06:03 PM   #48
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Quote:
Originally Posted by DannoXYZ View Post
Quick test is to look at slides when revving and see if they lift fully. Vacuum increases with RPM and you should see slides lift higher and higher. At mid-range, they should be at least 50% open.

If not, reach in there with your fingers and help lift slides up as you increase throttle. Does it redline now?

If so, you've got slide issue. New diaphragms may help. May also need to scrub out vacuum-ports from beginning to end. Also make sure vacuum-chambers are sealed.
I was able to get it to rev up tonight a little bit and saw that the slides were moving up as the throttle was increased. Correct me if I am wrong, but the air being sucked into the cylinder is what helps the slides to lift and in doing so lift the jet needle out of the emulsion tube so that more fuel can mix with the air and go into the engine.

Are the idle mixture screws the same on the 1986 and 1988 models?
tomsninja2020 is offline   Reply With Quote


Old September 16th, 2021, 06:04 AM   #49
ducatiman
ninjette.org certified postwhore
 
ducatiman's Avatar
 
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
"Are the idle mixture screws the same on the 1986 and 1988 models?"

yep
__________________________________________________
Gordon
Custom Carb Service

www.customcarbservices.com
ducatiman is offline   Reply With Quote


Old September 16th, 2021, 08:49 AM   #50
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by tomsninja2020 View Post
I was able to get it to rev up tonight a little bit and saw that the slides were moving up as the throttle was increased. Correct me if I am wrong, but the air being sucked into the cylinder is what helps the slides to lift and in doing so lift the jet needle out of the emulsion tube so that more fuel can mix with the air and go into the engine.
That's correct. Height of slide corresponds to volume of air going through carbs. It's fed and lifted by vacuum-port in front of carb-venturi. If you can confirm slides lift fully by redline, vacuum-port is working correctly.

It also lifts needle and increases gap to needle-jet. This allows matching fuel-volume to mix with air-volume. However, this is dependent upon fuel actually reaching carb-venturi to mix with incoming air. Unless secret and hidden passages in carb body have been thoroughly scrubbed, ultrasonic soaked and micro soda-blasted, there cannot be confirmation that sufficient petrol is flowing into carb-venturi.

You need to do some testing to gather data:

- starting: choke OFF vs. choke ON, is there a difference?
- revving past mid-range: shimmed needle vs. un-shimmed needle, is there a difference?

Current revving issues would indicate that carb passages are not sufficiently factory-fresh clean.

Last futzed with by DannoXYZ; September 16th, 2021 at 10:34 AM.
DannoXYZ is offline   Reply With Quote


Old September 16th, 2021, 09:47 AM   #51
ducatiman
ninjette.org certified postwhore
 
ducatiman's Avatar
 
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
"Current revving issues would indicate that carb passages are not sufficiently factory-fresh clean."


Agreed, my contention way back in mid-thread.
__________________________________________________
Gordon
Custom Carb Service

www.customcarbservices.com
ducatiman is offline   Reply With Quote


Old September 16th, 2021, 09:58 AM   #52
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
Quote:
Originally Posted by ducatiman View Post
Agreed, my contention way back in mid-thread.
It goes back farther than that.
Triple Jim is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 16th, 2021, 11:32 AM   #53
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Some references:

https://www.ninjette.org/forums/showthread.php?t=352293
DannoXYZ is offline   Reply With Quote


Old September 18th, 2021, 01:10 PM   #54
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Just a quick update:

Got the bike on the road. Ran fine, Idled like really really bad had to keep bliping throttle to keep it going when at a stop sign. Sometimes the idle hangs high and some times low and the oil pressure light keeps coming on at anything less then 2,000 RPM. Please help. I just cannot figure out the idle issues. Mixture screws are out about 2 turns each. I hear clicking coming from the valve cover and popping sounds when i let off the throttle that seem to come from exhaust header at the cylinder head.

Please help

Thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 18th, 2021, 01:30 PM   #55
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
Clicking from the valve cover indicates a badly misadjusted valve or something more serious.

Oil light coming on at any RPM below 2,000 could mean one of several things, the least bad being a faulty oil pressure switch, and that is not very likely.

Bad idle may be a result of the possible misadjusted valve, or carbs that need cleaning.
Triple Jim is offline   Reply With Quote


Old September 18th, 2021, 01:48 PM   #56
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Quote:
Originally Posted by Triple Jim View Post
Clicking from the valve cover indicates a badly miss-adjusted valve or something more serious.
What would you suggest I set the valves at. I think right the intakes are .004 and exhausts are at .006 inches? Oil is 10w40. If it thinned out would that cause the oil pressure light to come on?

Thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 18th, 2021, 01:48 PM   #57
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
Is it possible the sound is really from an exhaust leak at the head?

I don't think 10w-40 is going to cause your oil pressure light problem unless it's jet black and very high mileage.
Triple Jim is offline   Reply With Quote


Old September 18th, 2021, 01:51 PM   #58
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Quote:
Originally Posted by Triple Jim View Post
Is it possible the sound is really from an exhaust leak at the head?

I don't think 10w-40 is going to cause your oil pressure light problem unless it's jet black and very high mileage.
Sounds like it is coming from the right side of the top of the engine where the cam chain runs
tomsninja2020 is offline   Reply With Quote


Old September 18th, 2021, 02:07 PM   #59
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
Oh... maybe a cam chain or cam chain tensioner problem.
Triple Jim is offline   Reply With Quote


Old September 18th, 2021, 04:44 PM   #60
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Went for 2 test rides, results: no power cannot get past 5000 RPM no shimms on needles as of yet. Seems like battery is not staying charged.

Do you suggest another carb cleaning? Taking the top end apart and checking rockers and valve springs?

thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 18th, 2021, 05:04 PM   #61
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Yes try shimming needles to see if it improves, or gets worse. This would be useful data. Also do you have access to wideband-O2 with datalogging?


Oil-pressure relief valve may be clogged. Search for oil-pressure mod with shimming spring for slightly higher oil-pressure.

I had issue on my track bike with oil-pressure light always coming on 15-minutes into each and every session. Tried all sorts of different oil brands and weights. Finally found Motorex was only stuff that worked at track.
DannoXYZ is offline   Reply With Quote


Old September 19th, 2021, 02:40 PM   #62
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Went for three rides today. 2 ended in pushing the bike a few blocks home.

Still cannot get over 5000 RPM's. The bike boogs and loses power and if I don't let off the throttle it will die and will not start. Need to get rid of the boog but I don't know what to do. Still have low compression but I will deal with that later.

Thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 19th, 2021, 02:45 PM   #63
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
I didn't look back through all the posts... have you verified correct cam timing?
Triple Jim is offline   Reply With Quote


Old September 19th, 2021, 02:46 PM   #64
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
yes i did
tomsninja2020 is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 19th, 2021, 04:05 PM   #65
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Quote:
Originally Posted by DannoXYZ View Post
That's correct. Height of slide corresponds to volume of air going through carbs. It's fed and lifted by vacuum-port in front of carb-venturi. If you can confirm slides lift fully by redline, vacuum-port is working correctly.

It also lifts needle and increases gap to needle-jet. This allows matching fuel-volume to mix with air-volume. However, this is dependent upon fuel actually reaching carb-venturi to mix with incoming air. Unless secret and hidden passages in carb body have been thoroughly scrubbed, ultrasonic soaked and micro soda-blasted, there cannot be confirmation that sufficient petrol is flowing into carb-venturi.

You need to do some testing to gather data:

- starting: choke OFF vs. choke ON, is there a difference?
- revving past mid-range: shimmed needle vs. un-shimmed needle, is there a difference?

Current revving issues would indicate that carb passages are not sufficiently factory-fresh clean.
Lifting the slides by using my finger as the throttle plates are open makes the engine bogg, stall and die. If I could hold the slides shut then the engine might rev up but when they lift up the engines runs worse. What does that mean then?

Thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 19th, 2021, 04:08 PM   #66
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
Quote:
Originally Posted by tomsninja2020 View Post
If I could hold the slides shut then the engine might rev up but when they lift up the engines runs worse. What does that mean then?
It means that when the needles rise and contribute, the air/fuel mixture is not correct. When it starts to bog and you move the starter lever to the start position does it get better or worse?
Triple Jim is offline   Reply With Quote


Old September 19th, 2021, 05:05 PM   #67
ducatiman
ninjette.org certified postwhore
 
ducatiman's Avatar
 
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 like to establish confirmation that the needles are inserted into the slides first.....installed underneath (and not *over*) the spring seat.
__________________________________________________
Gordon
Custom Carb Service

www.customcarbservices.com
ducatiman is offline   Reply With Quote


Old September 19th, 2021, 05:06 PM   #68
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by tomsninja2020 View Post
Lifting the slides by using my finger as the throttle plates are open makes the engine bogg, stall and die. If I could hold the slides shut then the engine might rev up but when they lift up the engines runs worse. What does that mean then?

Thanks
Tom
means you are getting more air when slides open
BUT, you are not getting matching increase in petrol.
Something is wrong with carbs.
DannoXYZ is offline   Reply With Quote


Old September 19th, 2021, 05:37 PM   #69
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Quote:
Originally Posted by ducatiman View Post
I'd like to establish confirmation that the needles are inserted into the slides first.....installed underneath (and not *over*) the spring seat.
yes they are underneath. I have the same type of carb on my 150 scooter and it runs great. Granted it has good compression and vacuum. The only issues with the is finding the right main jet to give me power yet let the engine run cool enough.

Back to the ninja 250. what is the chance that the low compression would cause it not rev past 5000 RPM? IT just bogs and dies. If I back of the throttle I can usually keep it running.

Thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 19th, 2021, 07:32 PM   #70
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
Quote:
Originally Posted by tomsninja2020 View Post
what is the chance that the low compression would cause it not rev past 5000 RPM?
Not very big because a leaky cylinder has its worst symptoms at low speed when there's time for the leak to lose a lot of pressure.
Triple Jim is offline   Reply With Quote


Old September 20th, 2021, 07:23 AM   #71
jkv45
Rev Limiter
 
jkv45's Avatar
 
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
Quote:
Originally Posted by tomsninja2020 View Post
Went for three rides today. 2 ended in pushing the bike a few blocks home.

Still cannot get over 5000 RPM's. The bike boogs and loses power and if I don't let off the throttle it will die and will not start. Need to get rid of the boog but I don't know what to do. Still have low compression but I will deal with that later.

Thanks
Tom
Carbs are still not right.
jkv45 is offline   Reply With Quote


Old September 20th, 2021, 10:11 AM   #72
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by tomsninja2020 View Post
Back to the ninja 250. what is the chance that the low compression would cause it not rev past 5000 RPM? IT just bogs and dies. If I back of the throttle I can usually keep it running.
Yup, you're not getting enough extra petrol to match larger volume of air ingested at larger throttle-openings. Carbs needs some more work to get back to factory-fresh clean condition.
DannoXYZ is offline   Reply With Quote


Old September 22nd, 2021, 05:10 PM   #73
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Carbs soaked in Pine-Sol water mix for 24 hrs, and then dry with air. Took air nozzle and blew through all of the opening and passages that I could find on the carburetors. Unfortunately this did not improve the problem of not being able to rev up past 5,000 RPM.

Did not want to try it with the choke on but if it did work then what does that mean?

Also when setting the mixture screws at 2 turns out caused back firing through the carburetor. Kind of scary when it is shooting flames out to the air box. I set it to about 1.5 turns and at least I could get it started. I am about at my wits end with this engine. Apparently it is blown or something is not right. The battery will not stay charged and the bike will not stay running. It will run for a while and then all of a sudden it will just die.

I have put over $600 into it and I am about ready to say f__ it and sell it. Hell, my little 150 cc scooter does not give me as much of problem as this.

Please help?
Attached Images
File Type: jpg IMG_20210916_164255719_HDR.jpg (145.6 KB, 6 views)
File Type: jpg IMG_20210310_181613430~2.jpg (108.2 KB, 1 views)
tomsninja2020 is offline   Reply With Quote


Old September 22nd, 2021, 05:39 PM   #74
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
I understand that you said you already checked, but blowing and popping out the carbs is a symptom of valve timing being wrong.
Triple Jim is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 22nd, 2021, 06:06 PM   #75
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
My manual says 33 pins between the EX mark and IN mark on the cam shafts unless that is wrong. And the marks are level with the edge of the valve cover seating area. #2 cylinder at TDC correct? Should I use the flywheel mark or the screwdriver through the spark plug hole to get TDC?

Thanks
Tom
tomsninja2020 is offline   Reply With Quote


Old September 22nd, 2021, 07:44 PM   #76
Triple Jim
Guy Who Enjoys Riding
 
Triple Jim's Avatar
 
Name: Jim
Location: North Central North Carolina
Join Date: Jul 2016

Motorcycle(s): Ninja 250

Posts: A lot.
MOTM - Oct '18, Aug '17, Aug '16
As a double check, you could use a dial indicator in the spark plug hole, and look at the valves to see if the overlap is centered very close to TDC.
Triple Jim is offline   Reply With Quote


Old September 22nd, 2021, 09:10 PM   #77
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by tomsninja2020 View Post
Carbs soaked in Pine-Sol water mix for 24 hrs, and then dry with air. Took air nozzle and blew through all of the opening and passages that I could find on the carburetors. Unfortunately this did not improve the problem of not being able to rev up past 5,000 RPM.

Did not want to try it with the choke on but if it did work then what does that mean?
Means you've wasted tonnes of time doing stuff that doesn't make difference. Needs more objective, all-or-nothing, yes/no, black & white quantitative testing.

1. post photo of OEM needles compared to ones you had in carbs. That'll be black & white yes/no answer to whether they're contributing to your issues.

2. same with choke on/off test. If YES it's better; then we know for sure your mixtures are too lean with factory OEM configuration. If no, problems may be elsewhere. Although 5000rpm is high for little extra fuel from choke to really make noticeable difference. That's why you want to test starting with and without choke. Does it make a difference? yes/no very simple.

And given your cleaning procedure, we know for sure carbs aren't factory-fresh clean. That may be fine for bike that sat for 2-3 months and was running perfectly to begin with. But for bike that's been dormant for unknown number of years, carbs need full refurb and restoration job. Anything short of that will prolong existing problems.

https://www.ninjette.org/forums/show...56#post1294756


3. as for battery not holding charge, most likely is short that's draining battery. Again, very simple no-guessing black/white confirmation with objective multimeter. Do you have one and know how to use it to measure voltage, current and resistance? Well just measuring voltage is all you need in simple yes/no test:

b. 1st test, remove battery from bike and charge with trickle charger up to 13.0v. Disconnect charger and leave battery by itself on bench for 3-days. Measure battery voltage. What is this battery voltage?

b. 2nd test; fully charge up battery to 13.0v on exact same trickle charger. Disconnect from charger and re-install on bike, making sure both battery cables are secure. Let bike sit for 3-days again and measure battery voltage again. What is battery voltage?

c. How does battery voltage in test-A compare to test-B? if B is lower, this is indesputible objective black & white confirmation with numbers in yes/no all-or-nothing terms that you DO have short in harness that's draining battery. Simple. No guessing needed.
DannoXYZ is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old September 23rd, 2021, 06:20 AM   #78
jkv45
Rev Limiter
 
jkv45's Avatar
 
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
Very low battery voltage, by itself, will cause odd running problems as well.
jkv45 is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old September 23rd, 2021, 10:33 AM   #79
DannoXYZ
ninjette.org certified postwhore
 
Name: AKA JacRyann
Location: Mesa, AZ
Join Date: Dec 2011

Motorcycle(s): CB125T EX250F Ninja250R-street CBR250R-MC19 NSR350R-MC21 VF500F CBR600RR VFR750F

Posts: A lot.
MOTY - 2018, MOTM - Nov '17
Quote:
Originally Posted by jkv45 View Post
Very low battery voltage, by itself, will cause odd running problems as well.
Yeah! After being depleted by starting engine, weak battery won't have enough power to fully fire plugs. Nicer ignition systems adjust dwell (coil charge time) based upon battery-voltage. I doubt this system does that. So one more objective test to gather quantitative data

4. measure battery-voltage at idle.

5. measure battery-voltage at 5000rpms.

Those numbers will help narrow down this issue.
DannoXYZ is offline   Reply With Quote


Old September 26th, 2021, 02:51 PM   #80
tomsninja2020
ninjette.org member
 
Name: Tom
Location: Wells, MN
Join Date: Aug 2021

Motorcycle(s): 1986 Ninja 250, 2005 150 cc SUNL scooter

Posts: 37
Found this inside the engine. Spun rod bearing, is it worth putting a new rod bearing in or am I looking at a new crankshaft or engine? Cylinders and pistons are shot as well.

Thanks
Tom
Attached Images
File Type: jpg IMG_20210926_152813855_HDR.jpg (76.1 KB, 8 views)

Last futzed with by tomsninja2020; September 26th, 2021 at 02:54 PM. Reason: added info
tomsninja2020 is offline   Reply With Quote


Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
1986 ninja 250 james250ninja 1986 - 2007 Ninja 250R Tech Talk 17 September 5th, 2017 07:40 AM
1986 Ninja 250 parts DanteCoal Motorcycle-related 6 February 24th, 2016 10:07 AM
1986 ninja 250 james250ninja Motorcycle-related 2 May 28th, 2015 07:30 AM
1986 ninja 250 james250ninja Pictures 12 August 19th, 2014 05:58 AM
1986 ninja 250 build marines2060 1986 - 2007 Ninja 250R Tech Talk 40 May 24th, 2013 10:06 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


Motorcycle Safety Foundation

All times are GMT -7. The time now is 12:58 PM.


remote server monitor
Powered by vBulletin®
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2021 DragonByte Technologies Ltd.
Except where otherwise noted, all site contents are Copyright 2021 ninjette.org, All rights reserved.