May 17th, 2012, 01:54 AM | #1 |
ninjette.org newbie
Name: shadow
Location: Australia
Join Date: May 2012 Motorcycle(s): ninja 250r Posts: 7
|
Just a quick question
Hi my name is shadow.
I am new to this forum and bikes in general. I just have a quick question for any of the regulars with knowledge of ninja 250r's. I owned a 2010 ninja 250r for 6months which was the first bike I owned and rode. I bought it as a demo with 300kms on it. I kept it completely standard. Recently I sold it and bought a 2012 ninja 250r brand new. Right from the start I noticed a difference between the two bikes. most noticeably, when doing 100km/hr the old bike ran at 7500rpm. at the same speed the new one sits at 8500rpm. The new bike is more fun to ride and seems to have more acceleration/power when accelerating from 8000 to redline. However, it seems to use more fuel. Also, the new bike idles much easier and higher rpm. for example when started with choke on it jumps straight to 4000rpm. I have to adjust the choke straight away to get it back under 3000rpm. Today i had my first service done (bike has done 1200kms). After picking the bike up it is running very similar to my first ninja - ie sitting at 7500rpm when doing 100kms and idleing at lower rpm. I phoned the mechanic to ask what he adjusted and he said the only thing that has changed is the bike is now running thicker oil (recommended by kawasaki) as opposed to the factory oil which is thinner and he also put 10psi more tyre pressure in both tyres. Could this really account for the difference in rpm? I have asked a few people I know what they think and they said that the rpm at a particular speed can't change unless the cogs are altered. Is this true? Sorry for such a silly question but i am really confused. I prefered the bike when it was running slightly higher rpm even though it was using more fuel. It just seemed to accelerate better at higher rpm. |
|
May 17th, 2012, 06:10 AM | #2 |
ninjette.org dude
Name: 1 guess :-)
Location: SF Bay Area
Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much.
Blog Entries: 7
|
The tachs just aren't that accurate. With the same gearing and same tires, the engine would need to be turning the exact same speed for the same road speed across both bikes.
__________________________________________________
Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered) |
|
May 17th, 2012, 06:31 AM | #3 |
ninjette.org newbie
Name: shadow
Location: Australia
Join Date: May 2012 Motorcycle(s): ninja 250r Posts: 7
|
So, either i am losing my mind or something that was done at the service caused the tacho to read differently and bike to idle differently?
|
|
May 17th, 2012, 06:32 AM | #4 |
ninjette.org newbie
Name: shadow
Location: Australia
Join Date: May 2012 Motorcycle(s): ninja 250r Posts: 7
|
by the way, thanks for the reply alex. sorry i am such a noob!
|
|
May 17th, 2012, 06:34 AM | #5 |
ninjette.org dude
Name: 1 guess :-)
Location: SF Bay Area
Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much.
Blog Entries: 7
|
Idle differently is probably because he adjusted the idle knob back to spec, and 10 psi low in the tires would cause the revs to drop slightly at speed once they are aired up to spec. But no, there's nothing they could have done that would have actually made the bike's engine turn 1000 rpm lower at speed.
(P.S. Check your tire pressures much more often, running 10 psi low is not just a bad idea, it's truly dangerous)
__________________________________________________
Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered) |
|
May 17th, 2012, 06:40 AM | #6 |
ninjette.org newbie
Name: shadow
Location: Australia
Join Date: May 2012 Motorcycle(s): ninja 250r Posts: 7
|
I did ask him about idle knob. he said he didnt touch it. He did say there was a small oil leak which he fixed by tightening a clamp but doubt that affected anything. the bike was so different at low rpm that when I first took off the bike began to stall straight away so I tried to give it more gas to prevent this from happening and there just was no power at all.
I will take it for a ride tomorrow and see how it is going. |
|
May 17th, 2012, 07:52 AM | #7 |
Daily Ninjette rider
Name: Hernan
Location: Florida
Join Date: Mar 2011 Motorcycle(s): 2007 Ninja 250 Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
|
Could it be that your first bike had a modification done to the sprockets?
Changing the front sprocket to more teeth for reducing rpm's at high speeds is a common modification. Did your mechanic adjust play of the clutch lever? If rpm's changed 1000 (8500 to 7500) at same bike speed (100 km/h), the clutch was slipping before for bad adjustment or bad oil.
__________________________________________________
Motofool .................................Never ride faster than your guardian angel can fly "Mankind is composed of two sorts of men — those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - José Martí |
|
May 17th, 2012, 05:31 PM | #8 | |
ninjette.org newbie
Name: shadow
Location: Australia
Join Date: May 2012 Motorcycle(s): ninja 250r Posts: 7
|
Quote:
The mechanic said that there was an oil leak of some kind which he fixed by tightening something. Could this have been related to slipping clutch? Would I have noticed a slipping clutch while riding the motorcycle for 1200kms before having the bike serviced? Thanks |
|
|
May 18th, 2012, 05:41 AM | #9 |
Daily Ninjette rider
Name: Hernan
Location: Florida
Join Date: Mar 2011 Motorcycle(s): 2007 Ninja 250 Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
|
Yes, the clutch must have been slipping during the time the engine's rpm's were higher.
I say that because there is a solid transmission from the crankshaft to the rear wheel. The only flexible transmission rate is introduced by the clutch. When the clutch is commanded to function, their multiple friction discs start an in-oil-slip that allows the transmission aft that point to slow down respect to the rpm's of the crankshaft (on which end the clutch is installed). The conditions that I mentioned make some little slip among the discs happen when the clutch is not commanded to engage. Check this link: http://www.dansmc.com/clutches.htm
__________________________________________________
Motofool .................................Never ride faster than your guardian angel can fly "Mankind is composed of two sorts of men — those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - José Martí |
|
May 18th, 2012, 06:30 PM | #10 | |
ninjette.org newbie
Name: shadow
Location: Australia
Join Date: May 2012 Motorcycle(s): ninja 250r Posts: 7
|
Quote:
After first service, the fixing of a small oil leak or tightening of certain clamps/parts has corrected this which has changed idle and rpm at 100km/h. Now my bike is running as it should which is exactly like my first 250r. does that make sense? |
|
|
May 18th, 2012, 07:27 PM | #11 |
ninjette.org dude
Name: 1 guess :-)
Location: SF Bay Area
Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much.
Blog Entries: 7
|
No, sorry, it doesn't. A slipping clutch doesn't cause a bike (or any vehicle) to have its engine run a stable percentage higher, that when fixed runs lower. If it was slipping under throttle, it would show quite variable revs, even at the same road speed.
__________________________________________________
Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered) |
|
May 18th, 2012, 10:34 PM | #12 | |
ninjette.org newbie
Name: shadow
Location: Australia
Join Date: May 2012 Motorcycle(s): ninja 250r Posts: 7
|
Quote:
However, I know that I am not and that something has changed. Was really hoping the slipping clutch thing was the explanation. I am sure the bike is as it should be now. It's just my personality to sought an explanation as to why it wasnt previous to my service. Ride safe and all the best, shadow. |
|
|
May 18th, 2012, 10:52 PM | #13 |
ninjette.org dude
Name: 1 guess :-)
Location: SF Bay Area
Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much.
Blog Entries: 7
|
Heck, no worries! We're as eager to figure out what might be causing it as you are. I didn't want to bring this one up as it's unlikely, but it's another cause for the tach behaving a little strangely:
http://www.ninjette.org/wiki/Ignitor_problem
__________________________________________________
Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered) |
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
quick question | Electronic M | 2013 - 2017 Ninja 300 Tech Talk | 57 | March 17th, 2015 04:41 AM |
Quick question | kennetht | 2008 - 2012 Ninja 250R Tech Talk | 5 | March 26th, 2014 11:40 AM |
Quick Question | PsHYk | 2008 - 2012 Ninja 250R Tech Talk | 3 | June 10th, 2012 02:58 PM |
Quick Question! | shiftdrift06 | 1986 - 2007 Ninja 250R Tech Talk | 4 | March 1st, 2012 08:31 PM |
Quick Shim question | shadowskater | 2008 - 2012 Ninja 250R Tech Talk | 7 | February 28th, 2011 08:41 PM |
|
|