DIY- Sprocket Swap - Page 5

Alex · April 8th, 2014, 11:29 AM

Quote:

Originally Posted by headshrink

I read on another board that 1T on the counter-sprocket is aprox. equal to 3T on the rear (not sure, just repeating).

It's because the rear sprocket has 3 times the teeth of the front. (stock is 14/45, common mod is 15/45). Changing from 14/45 to 14/42 would be the exact same thing as going to 15/45; the reason people don't do that is because the rear sprocket is more expensive, and the chain length might be affected a little bit more.

headshrink · April 8th, 2014, 11:35 AM

Makes sense, thanks!

If memory serves, an additional factor is it becomes problematic fitment wise to add anything more than 1T to the front of our bike, thus the rear is changed. I don't hear too many people wanting this ratio, but I remember fitment being discussed in the early days.

FBR_BDavis · March 22nd, 2015, 06:39 PM

Having a helluva time getting the front sprocket off of my Ninjette.. Looks like I'm going to have to remove my Musarri pipe and use the 2x4 trick to break it loose.. :/

I did manage to swap out the stock 45T rear sprocket for a Vortex 43T rear sprocket, though.. Maybe it's just me, but the difference is definitely noticable in how the bike rides.. It seems to be smoother overall.. I love it.. I'm hoping that when I go from the stock 14T front to the Vortex 15T front, it improves even more..

headshrink · March 22nd, 2015, 09:10 PM

This is one of those times an impact wrench is best. Those who have been around a while may remember when I damaged my bike trying to apply more force trying to get that mother hugger off.

FBR_BDavis · March 23rd, 2015, 06:08 AM

My oldest son is an Audi/Porsche mechanic down in Baltimore.. I'll probably enlist his services for this one, since I know he has all of the tools necessary.. Better safe than sorry..

wardie · March 24th, 2015, 04:13 AM

When I got my Ninja last year (2012 out of crate new) I carefully broke in the motor not exceeding the rpm guidelines or lugging the motor . I had stock gearing. Upon coming up to my first 1,000 mile trip on her I changed out the stock gearing to 15/41 to lower highway rpms at 72 mph. The gearing kept the engine in the rpm range that I wanted but found that I could not pull any higher than 93 mph (GPS verified). If I was to do over I would probably look at 15/43, 15/42 which would help acceleration in top gears.

Overall I can't complain it's a minor inconvenience and really who cares if the top speed is 93 or 98??

Yes the front sprocket is on there. I put bike in gear had someone sit on bike and depress the rear brake pedal and I had a long 1/2" breaker bar.

Make sure you use a torque wrench and put the new sprocket back on properly. Good luck and enjoy the ride

FBR_BDavis · March 24th, 2015, 05:09 AM

I looked over various sprocket combinations to find the gearing that I thought would be best for my wants/needs.. The 15/43 *should* be the best overall option for my riding purposes, with quite a bit of highway riding mixed in with the usual suburban roads..

April 8th, 2014, 11:35 AM	#162
headshrink ninjette.org certified postwhore Name: Bob Location: CA Join Date: Dec 2008 Motorcycle(s): '08 Ninja 250r, '14 CBR500r Posts: A lot.	Makes sense, thanks! If memory serves, an additional factor is it becomes problematic fitment wise to add anything more than 1T to the front of our bike, thus the rear is changed. I don't hear too many people wanting this ratio, but I remember fitment being discussed in the early days. __________________________________________________ Honda Interceptor VFR800 DLX (2014, 8th gen) Honda CBR500r (2014) - FOR SALE Kawi Ninja 250r (2008) - Restored and passed-down within family, only to be abandoned

March 22nd, 2015, 09:10 PM	#164
headshrink ninjette.org certified postwhore Name: Bob Location: CA Join Date: Dec 2008 Motorcycle(s): '08 Ninja 250r, '14 CBR500r Posts: A lot.	This is one of those times an impact wrench is best. Those who have been around a while may remember when I damaged my bike trying to apply more force trying to get that mother hugger off. __________________________________________________ Honda Interceptor VFR800 DLX (2014, 8th gen) Honda CBR500r (2014) - FOR SALE Kawi Ninja 250r (2008) - Restored and passed-down within family, only to be abandoned

March 24th, 2015, 04:13 AM	#166
wardie ninjette.org guru Name: Larry Location: Youngstown, Ohio Join Date: Oct 2011 Motorcycle(s): 06 KLR 650,12 250 Ninja, 86 DR 125, 07 CRF 100, 09 Tomos Streetmate LEL Record Holder, 88 K100 RT Posts: 434	gearing When I got my Ninja last year (2012 out of crate new) I carefully broke in the motor not exceeding the rpm guidelines or lugging the motor . I had stock gearing. Upon coming up to my first 1,000 mile trip on her I changed out the stock gearing to 15/41 to lower highway rpms at 72 mph. The gearing kept the engine in the rpm range that I wanted but found that I could not pull any higher than 93 mph (GPS verified). If I was to do over I would probably look at 15/43, 15/42 which would help acceleration in top gears. Overall I can't complain it's a minor inconvenience and really who cares if the top speed is 93 or 98?? Yes the front sprocket is on there. I put bike in gear had someone sit on bike and depress the rear brake pedal and I had a long 1/2" breaker bar. Make sure you use a torque wrench and put the new sprocket back on properly. Good luck and enjoy the ride __________________________________________________ wardie

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March 22nd, 2015, 06:39 PM	#163
FBR_BDavis ninjette.org member Name: Butch Location: Bridgeton, NJ Join Date: Jan 2015 Motorcycle(s): 2009 Kawasaki Ninja 250R Posts: 121	Having a helluva time getting the front sprocket off of my Ninjette.. Looks like I'm going to have to remove my Musarri pipe and use the 2x4 trick to break it loose.. :/ I did manage to swap out the stock 45T rear sprocket for a Vortex 43T rear sprocket, though.. Maybe it's just me, but the difference is definitely noticable in how the bike rides.. It seems to be smoother overall.. I love it.. I'm hoping that when I go from the stock 14T front to the Vortex 15T front, it improves even more..

March 23rd, 2015, 06:08 AM	#165
FBR_BDavis ninjette.org member Name: Butch Location: Bridgeton, NJ Join Date: Jan 2015 Motorcycle(s): 2009 Kawasaki Ninja 250R Posts: 121	My oldest son is an Audi/Porsche mechanic down in Baltimore.. I'll probably enlist his services for this one, since I know he has all of the tools necessary.. Better safe than sorry..

March 24th, 2015, 05:09 AM	#167
FBR_BDavis ninjette.org member Name: Butch Location: Bridgeton, NJ Join Date: Jan 2015 Motorcycle(s): 2009 Kawasaki Ninja 250R Posts: 121	I looked over various sprocket combinations to find the gearing that I thought would be best for my wants/needs.. The 15/43 should be the best overall option for my riding purposes, with quite a bit of highway riding mixed in with the usual suburban roads..