Inaccurate Tachometer

ahoy11 · April 28th, 2012, 02:50 PM

The tachometer on my '09 ninja 250 started to show higher RPMs than it used to. The idle RPM went from ~1500 to ~3000. In fact, RPMs seems to have doubled. Now I rev often to the red line before I feel the bike is ready for an up shift.

The engine is either actually reaching the higher RPMs, or the tachometer is wrong. I believe the tachometer is inaccurate, because by my previous experience, the engine doesn't sound like it's revving as high as the tachometer displays.

Anyone have any suggestions?

Trying to think how it could have happened, I remember that right before I noticed this, I stalled the bike on a traffic light, and started the engine again without the clutch being fully pulled in. Could that have changed anything?

Thanks for any insights!

Felipe the Ant · April 28th, 2012, 03:51 PM

Loose battery connections cause strange things to happen. My tach was all over the place whenever I used the high beam and it turned out to be a loose connection.

Otherwise I'm not too sure, a crossed wire causing it to pick up from both coils? (It should only read from one)

Have you done any work/mods recently? Ever? Are you the original owner?

etiainen · April 28th, 2012, 04:23 PM

Is it when it gets hot outside? This is a known issue with the stock ignitor.

It happened to me as well.

Felipe the Ant · April 28th, 2012, 06:59 PM

Quote:

Originally Posted by etiainen

Is it when it gets hot outside? This is a known issue with the stock ignitor.

It happened to me as well.

It doesn't double it, it just reads a little higher. Maybe 500rpm, not near 1500+

etiainen · April 28th, 2012, 07:13 PM

Mine read 1k high.

ahoy11 · April 29th, 2012, 07:18 PM

Actually now I suspect it is a clutch slippage issue. The clutch may not have been fully disengaged. I tried to adjust the clutch cables today, on both the upper end where the lever is, and at the lower end near the oil gauge, but I don't quite know how to adjust, and didn't fix the issue.
Anyone think the clutch slippage could be the real issue there? And I need a better guide for clutch cable adjustment than what is in the manual.

Felipe the Ant · April 29th, 2012, 09:20 PM

No problem with a clutch will make it idle at 3000rpm. And I think you mean engage

Also in the OP you said it doesn't sound like it's ready to shift. You'd hear the revs skyrocket to redline if the clutch slipped.

Did you check the battery connections yet?

alex.s · April 29th, 2012, 10:28 PM

dont look down

ahoy11 · April 30th, 2012, 10:07 AM

No I haven't checked the battery connections yet.
Is it just checking the connections at the battery terminal? Or is there another connection I should check?

I did mean "disengage". If the clutch is not fully released/disengaged, wouldn't the engine run at a higher RPM than when clutch is engaged?

ahoy11 · April 30th, 2012, 10:09 AM

oh wait, nm, I did mean "engaged". right, I was wondering whether the clutch is fully engaged.

Felipe the Ant · May 1st, 2012, 06:07 AM

Yeah, make sure they're tight on the battery

If the clutch wasn't fully engaged the revs would shoot up and you'd have problems moving.

CZroe · May 1st, 2012, 03:49 PM

Make sure the battery is good too. My friend had one that tested good but the engine would rev when the brake light came on until he replaced the battery or connected a portable jump-start battery.

Felipe the Ant · May 2nd, 2012, 06:12 AM

Quote:

Originally Posted by CZroe

Make sure the battery is good too. My friend had one that tested good but the engine would rev when the brake light came on until he replaced the battery or connected a portable jump-start battery.

This too, good call. And if you're gonna test it use a conductance tester. A voltmeter won't tell you if it's good

CZroe · May 2nd, 2012, 08:18 AM

Quote:

Originally Posted by Felipe the Ant

This too, good call. And if you're gonna test it use a conductance tester. A voltmeter won't tell you if it's good

I don't know what he used but he took it to an auto store with free battery testing and they said it was "all good." I've had them fail perfectly good batteries just to sell you a new one. :/

Link to original page on YouTube.

Felipe the Ant · May 2nd, 2012, 08:43 AM

They do a conductance test

April 28th, 2012, 02:50 PM	#1
ahoy11 ninjette.org newbie Name: Eugene Location: Toronto, Canada Join Date: Apr 2012 Motorcycle(s): 09 Ninja 250 Posts: 4	Inaccurate Tachometer The tachometer on my '09 ninja 250 started to show higher RPMs than it used to. The idle RPM went from ~1500 to ~3000. In fact, RPMs seems to have doubled. Now I rev often to the red line before I feel the bike is ready for an up shift. The engine is either actually reaching the higher RPMs, or the tachometer is wrong. I believe the tachometer is inaccurate, because by my previous experience, the engine doesn't sound like it's revving as high as the tachometer displays. Anyone have any suggestions? Trying to think how it could have happened, I remember that right before I noticed this, I stalled the bike on a traffic light, and started the engine again without the clutch being fully pulled in. Could that have changed anything? Thanks for any insights!

April 28th, 2012, 03:51 PM	#2
Felipe the Ant ninjette.org sage Name: . Location: . Join Date: May 2011 Motorcycle(s): 2011 Ninja 250R SE GREEN! Posts: 562	Loose battery connections cause strange things to happen. My tach was all over the place whenever I used the high beam and it turned out to be a loose connection. Otherwise I'm not too sure, a crossed wire causing it to pick up from both coils? (It should only read from one) Have you done any work/mods recently? Ever? Are you the original owner? __________________________________________________ Trust me, I'm a banana!

April 29th, 2012, 09:20 PM	#7
Felipe the Ant ninjette.org sage Name: . Location: . Join Date: May 2011 Motorcycle(s): 2011 Ninja 250R SE GREEN! Posts: 562	No problem with a clutch will make it idle at 3000rpm. And I think you mean engage Also in the OP you said it doesn't sound like it's ready to shift. You'd hear the revs skyrocket to redline if the clutch slipped. Did you check the battery connections yet? __________________________________________________ Trust me, I'm a banana!

April 29th, 2012, 10:28 PM	#8
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	dont look down __________________________________________________

May 1st, 2012, 06:07 AM	#11
Felipe the Ant ninjette.org sage Name: . Location: . Join Date: May 2011 Motorcycle(s): 2011 Ninja 250R SE GREEN! Posts: 562	Yeah, make sure they're tight on the battery If the clutch wasn't fully engaged the revs would shoot up and you'd have problems moving. __________________________________________________ Trust me, I'm a banana!

April 28th, 2012, 04:23 PM	#3
etiainen CBR250R Traitor Name: Jon Location: Greater Philadelphia Area Join Date: Jun 2011 Motorcycle(s): 2011 Red CBR250R 2009 Ninja 250r SE(With 2008 Fairings)(sold) Posts: 924	Is it when it gets hot outside? This is a known issue with the stock ignitor. It happened to me as well.

April 28th, 2012, 07:13 PM	#5
etiainen CBR250R Traitor Name: Jon Location: Greater Philadelphia Area Join Date: Jun 2011 Motorcycle(s): 2011 Red CBR250R 2009 Ninja 250r SE(With 2008 Fairings)(sold) Posts: 924	Mine read 1k high.

April 29th, 2012, 07:18 PM	#6
ahoy11 ninjette.org newbie Name: Eugene Location: Toronto, Canada Join Date: Apr 2012 Motorcycle(s): 09 Ninja 250 Posts: 4	Actually now I suspect it is a clutch slippage issue. The clutch may not have been fully disengaged. I tried to adjust the clutch cables today, on both the upper end where the lever is, and at the lower end near the oil gauge, but I don't quite know how to adjust, and didn't fix the issue. Anyone think the clutch slippage could be the real issue there? And I need a better guide for clutch cable adjustment than what is in the manual.

April 30th, 2012, 10:07 AM	#9
ahoy11 ninjette.org newbie Name: Eugene Location: Toronto, Canada Join Date: Apr 2012 Motorcycle(s): 09 Ninja 250 Posts: 4	No I haven't checked the battery connections yet. Is it just checking the connections at the battery terminal? Or is there another connection I should check? I did mean "disengage". If the clutch is not fully released/disengaged, wouldn't the engine run at a higher RPM than when clutch is engaged?

April 30th, 2012, 10:09 AM	#10
ahoy11 ninjette.org newbie Name: Eugene Location: Toronto, Canada Join Date: Apr 2012 Motorcycle(s): 09 Ninja 250 Posts: 4	oh wait, nm, I did mean "engaged". right, I was wondering whether the clutch is fully engaged.

May 1st, 2012, 03:49 PM	#12
CZroe CPT Falcon Name: J.Emmett Turner Location: Newnan, GA Join Date: Apr 2009 Motorcycle(s): '08 CP Blue EX250J, '97 unpainted EX250F, 2nd '97 unpainted EX250F (no engine), '07 black EX250F Posts: A lot.	Make sure the battery is good too. My friend had one that tested good but the engine would rev when the brake light came on until he replaced the battery or connected a portable jump-start battery.

May 2nd, 2012, 08:43 AM	#15
Felipe the Ant ninjette.org sage Name: . Location: . Join Date: May 2011 Motorcycle(s): 2011 Ninja 250R SE GREEN! Posts: 562	They do a conductance test __________________________________________________ Trust me, I'm a banana!

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