Sprocket change?

[pismocycleguy]

I had to remove two links. The sprocket was actually a fair amount smaller. As far as the acceleration, like I said in my other post, I felt no real difference in the feel of the pull. It accelerates just as hard if you want it to or you can lug it more and keep the rpm's down easier. I think the torque was under utilized in this bike and I actually feel like it accelerates harder because the torque gets more use and the gear lasts longer. I do not feel like I use the clutch anymore to get the bike going and even with my girlfriend on the back it pulls just as hard at all speeds. Not sure why Honda did not use the 39 to start with but in my opinion it is a great choice for those looking to drop rpm's.

Bamo,
Thanks for the follow up information. I'm only going with the 2 tooth reduction on my NC. That is the same sprocket reduction that I used on my 2011 Kawasaki Versys. It allowed me to at least get across the intersection before the need to shift to 2nd gear. I'm hoping for the same effect on the NC.

 

[Antarius]

I had to remove two links. The sprocket was actually a fair amount smaller. As far as the acceleration, like I said in my other post, I felt no real difference in the feel of the pull. It accelerates just as hard if you want it to or you can lug it more and keep the rpm's down easier. I think the torque was under utilized in this bike and I actually feel like it accelerates harder because the torque gets more use and the gear lasts longer. I do not feel like I use the clutch anymore to get the bike going and even with my girlfriend on the back it pulls just as hard at all speeds. Not sure why Honda did not use the 39 to start with but in my opinion it is a great choice for those looking to drop rpm's.

How is it doing on the freeway? Does it feel like it's lugging at 65 or does it feel the same as before, just a little lower RPM?

 

[pismocycleguy]

SprocketCenter.com? Chad is there and could know where to order something that fits. He's a good guy.

I ordered a sprocket from Chad at Sprocket Center on Monday, Nov. 11th. Chad said I would receive it in two days. He told me he had several 41 tooth sprockets in stock.

 

[Bamo]

At highway speeds I do not notice any more lag. I took my girlfriend down the interstate with all the luggage on the bike and loaded down. Just the RPM's were lower, no more lag.

 

[pismocycleguy]

I ordered a sprocket from Chad at Sprocket Center on Monday, Nov. 11th. Chad said I would receive it in two days. He told me he had several 41 tooth sprockets in stock.

I received the 41 tooth sprocket today from Chad via Priority Mail. Fast service.

 

[turbodieseli4i6]

At highway speeds I do not notice any more lag. I took my girlfriend down the interstate with all the luggage on the bike and loaded down. Just the RPM's were lower, no more lag.

Let us know if it help your fuel mileage. I may do the same thing on my next chain/sprocket service.

 

[lipsee]

At highway speeds I do not notice any more lag. I took my girlfriend down the interstate with all the luggage on the bike and loaded down. Just the RPM's were lower, no more lag.

Thanks Bamo,,As I said a little earlier I am perfectly happy with the stock gearing,but I feel the bike could take abit of lower gearing,as long you do not mind dropping down a cog on uphills,,but how is it moving off in 1st??? and Bamo if you get chance ,,can you check your mpg...I for one would be interested....

 

[Bamo]

All of my riding has been out of the ordinary lately. I will try to fill up and ride this weekend so i can give you some MPG numbers.

 

[Bamo]

Taking off in first is not really any different to me. I don't find myself slipping the clutch anymore than normal. I do notice that I have more time till I need to shift though. Seems like a lot of positives and no real negatives. I am an optimist though.

 

[L18flyboy]

On my Ninja 250 (2009) I replaced the front sprocket at perhaps 10K miles to add one tooth and later replaced the rear sprocket to remove 1 tooth. The intent was to reduce RPMs for engine wear and improved gas mileage since this was my primary commute bike doing nearly 100 miles per day round trip. On this bike the engine turns about twice the RPM of a typical bike for a given freeway speed in high gear. I was quite happy with the results and figured I was reducing engine wear which would prolong the life of the bike. I estimate that I was turning 10-15% fewer RPMs at freeway speed (70-80MPH indicated being typical for my commute). Gas mileage was improved by these sprocket changes, with the acceptance of slower acceleration. Engine noise and vibration at freeway speeds were greatly improved.

About 2000 miles ago I needed to replace the rear tire, which was a 130/70-17. I happened to have a pair of 130/90-17 street tires gathering dust in the garage that were intended for a second set of rims on my KLR650. Curiosity got the better of me and I decided to see if if the larger tire would fit on the Ninja. Clearance was tight, but with a slightly longer chain the larger tire did fit. The last 10 fill ups prior to installing the larger tire were all in the 55-59 MPG range. Since changing to the larger tire I've gotten 71, 74, 68, 67, 68, and 74 MPG on my last 6 tanks. Yes, the bike does accelerate more slowly, though I haven't had any trouble beating the first cars off the line at the stop lights when I filter through traffic. I'm sure there will be some who would caution about the changes in the bike geometry, though for the style of riding I do on this bike I'm comfortable with how the bike handles -- which frankly is not noticeably different to me other than acceleration. If I were dragging a knee or doing track days then the changes might be an issue. The bike now has 61K miles on it.

Bottom line is this tire change resulted in a larger bump in MPG than the sprocket changes. From that experience, I have am pondering going to a larger tire on the NC700 when it is time to replace my original rear tire which now has 9000 miles on it.

 

[Antarius]

Me personally, I'd rather find a 1 tooth larger FRONT sprocket rather than a smaller rear sprocket; But I don't seem to think that's an option these days.

 

[MiG Angel]

Good info here but we never really did hear the avg effects on mpg from the sprocket changes. My cruise speed seems to be a constant 70-75 mph and I'm getting mpg in the low 50's. I'm willing to try a smaller rear but I'd really like some data from the members who have experimented with the gearing.

 

[pismocycleguy]

Good info here but we never really did hear the avg effects on mpg from the sprocket changes. My cruise speed seems to be a constant 70-75 mph and I'm getting mpg in the low 50's. I'm willing to try a smaller rear but I'd really like some data from the members who have experimented with the gearing.

Hi MiG,
I have the 41 tooth rear sprocket on my bike. I really like the slight reduction in engine speed and noise with the smaller sprocket, and the need to shift less. My speedometer now reads closer to my actual speed, according to GPS. After I first installed the sprocket I thought I was actually going slower but it was just a reduction in noise and a more accurate reading. My gas mileage increased by about 3 mpg. I used the stock chain, no removal of chain links. I'm happy with the results.
Hope this helps.
Pismo

 

[bamamate]

I can tell you that going down a tooth on the front will drop the MPG by almost 10 MPG. Thought I'd throw that out there for the thread.

 

[Bugsy]

This thread's very interesting to me.
I'm obsessed not only with mileage, but in the past I've found that particularly with six speed transmissions, I liked the increased spacing between gears a higher gearing gives.
I also note the DCT model comes stock with a 39 tooth rear sprocket but my manual version uses a 43 tooth rear. Based on my personal quirks and the different specs I bought a 39 tooth, though I haven't installed it yet (it's deeply winter here). The bike's fully broken in, but I guess I'll wait to put some miles (and mileages) on the stock setup before I try the new sprocket.
Time was, you could do all the sprocket fumbling you wanted and still have an accurate (front-wheel-driven) speedometer, but that was before electronics....

 

[670cc]

I also note the DCT model comes stock with a 39 tooth rear sprocket but my manual version uses a 43 tooth rear.

Yes, the DCT and manual models have different rear sprocket sizes, but it may not mean what you think. The internal transmission gearing is different on the two models. If you look at the overall gearing charts, top gear overall ratio is the same on the two models, despite the rear sprockets being different.

 

[Bugsy]

I did notice the gearing differences though I didn't work out the exact overall ratio for both.
To me, it just meant there was an OEM sprocket that would fit that would go in the direction I (think I) want to go. I admit, almost 10% is a step. As I say, when the snow melts I'll see what I think of stock, then decide if I think a change will improve mileage.
I admit, that's getting down below 2500 RPM at a real 50 mph; it will take some shifting if one wants to stir things up, and it looks like you're doing quite well with your mileage.

 

[Antarius]

You can go to: Gearing Commander: Motorcycle Speed, RPM, Chain & Sprockets Calculator to see a very good estimate of what your RPM's and speed will be with a given sprocket and chain setup.

 

[ncBunny]

Hey @bigjay... Looks like this thread is a little older but I was just curious which 45t sprocket did you buy?

Any snags with installing it and are things still going well? I <3 this bike but feel it needs a little more zip somedays.

 

[Grrant1058]

Just fitted a 1 tooth smaller (16t) front sprocket with standard 43t rear sprocket. For Australian speed limit of 100 kmh (60mph) this has made my 2016 NC750X better/ easier to ride. Has a little more punch but more importantly I don't have to down change on steeper inclinations on the highway. This change was made 4 tanks of fuel back and interestingly, my fuel economy has improved from 31kml to 33kml. Definitely worth doing for our speed limit, however, now my speedo is out by 10% so a speedo healer is on the way.