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Discussion Starter #1
Well, since my chain was done at 20,000 km (if I was a better chain-keeper, I’m sure it would have lasted longer) I went with a 15T countershaft sprocket. It always seemed like a good idea, but when I first got the 300, I had a very steep driveway with a tight turn into my parking space, so the 14T made sense. Now I have a less tilted entry to my parking, but I have to squeeze between a post and my car. Anyway, by that time, I figured I would wait until I needed a chain/sprocket replacement. Here are my thoughts:

I am surprised at how noticeable the change is. I have changed gearing on bikes before, but not on a long-term street bike that I ride on the same roads every day. If you change gearing to suit a particular track, you don’t have a basis for direct comparison. Now, I do, since I ride the same roads all the time. My commute is urban, but winding and low traffic. I tend not to watch my speedo, but ride by sound and feel. On paper, I suspect the change is insignificant, but for the speeds I ride, the gearing has mostly moved the RPMs into a better spot.

The bike has less “snap” off the line. This is not necessarily a bad thing. I would have to put more thought into doing a wheelie, but I’m not an idiot, so I don’t do wheelies. In the first three gears, I would probably have to pay more attention to my revs to get max acceleration, but after third, the difference is negligible, and I don’t live at a racetrack anyway. Besides, having to make the 1-2 shift so quickly after launch with 14T probably negates the difference. Engine braking is softened; mostly a good thing, since a single has more than enough of that.

The speedo is corrected. I have a speed sign on my way home from work, and at 60 kph indicated, it now registers 58 or 59. Actually, I have noticed that when I actually DO look at my speedo, I now think “really, that’s all I’m doing?” since it was so optimistic before.

The main reason most people switch to 15T is to calm the RPMs at highway speeds; I actually haven’t gotten out onto the highway since the swap, but I already like the change anyway.

I can see why the bike is geared the way it is, given the target demographic, but I think it is a superior bike with a 15T sprocket.
 

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where the stock gearing is handy [aside from pillion/other load. steep start etc]
is getting away from lights between cars after filtering to the front..
aside from those who want to race, they cant be trusted to get away cleanly and in the straight line you take [etc].. its still a matter of awareness and timing, waiting in first, watching hooded lights drivers often cant see, but even as a lightweight rider i appreciate the quick takeoff into clear road space..
otherwise for long runs and smoother engine braking a sprocket change is yet another practical gearing option for the motorcyclist..
 

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Well, since my chain was done at 20,000 km (if I was a better chain-keeper, I’m sure it would have lasted longer) I went with a 15T countershaft sprocket.
I only got 20,000km out of my OEM chain and I thought I did a good job of maintaining it so i wouldn't beat yourself up.


The speedo is corrected. I have a speed sign on my way home from work, and at 60 kph indicated, it now registers 58 or 59. Actually, I have noticed that when I actually DO look at my speedo, I now think “really, that’s all I’m doing?” since it was so optimistic before.
This is an added bonus of the sprocket change folk probably dont know about. The only thing is your ODO will be out by 7% now. Can mess with your fuel usage calcs if doing any. Lower mileage on the clock than actual at resale time though!


I can see why the bike is geared the way it is, given the target demographic, but I think it is a superior bike with a 15T sprocket.
I agree, particularly if your doing open road running. It's a single cylinder bike with power in the mid-range, so why did they gear it like a revvy parallel twin? I even dropped two teeth off the rear sprocket as well to get the bike revving how I like it in top gear. Only down side of that was now the speedo read slow!
 

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Discussion Starter #4
I can’t remember if I checked the odometer accuracy before. Are they accurate when the speedo isn’t?

As for chain life, I don’t really think 20,000 km is that terrible. I was surprised at how much it stretched in the last couple thousand km, though. When new, I adjusted a couple of times in the first few thousand km, then rare small adjustments until a few months ago. I had tweaked the tension, and thought to myself “gonna need a new chain next spring!” Within no time at all, it was to the end of the indicator and still not tight enough.
 

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I can’t remember if I checked the odometer accuracy before. Are they accurate when the speedo isn’t?

As for chain life, I don’t really think 20,000 km is that terrible. I was surprised at how much it stretched in the last couple thousand km, though. When new, I adjusted a couple of times in the first few thousand km, then rare small adjustments until a few months ago. I had tweaked the tension, and thought to myself “gonna need a new chain next spring!” Within no time at all, it was to the end of the indicator and still not tight enough.
I think that last bit of accelerated wear is from once the o rings get worn and the inner lube on the pins gets washed out. Guessing.

Regarding ODO: Yep, it's accurate from the factory even though the speedo isnt. Maybe they are trying to make the bike seem faster than it actually is in the reviews etc.
 

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Hi Dan, just curious if and how the bike now runs going uphill? I concern of mine, besides two-up was the way it handles uphill runs with the 15T. Thanks
 

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J found when I di go + 1 on my front sprocket on my 300 R... the Speedo seemed spot on..yet the ODO when observed in a measured KM distance was inaccurate (low). So of course mileage was less that it actually was...and calculating L/KM..or MPG (Imperial) was a bit off too. None the less I did like the change.
 
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Discussion Starter #9
Hi Dan, just curious if and how the bike now runs going uphill? I concern of mine, besides two-up was the way it handles uphill runs with the 15T. Thanks
It’s very hilly here, and the bike has no issues with it. Pulling away from a stop on a steep hill requires a bit more slip, and I have to be a bit more mindful of the revs in general, but overall it’s a better setup for me. I never ride two-up, so I can’t speak about that, but if I did so regularly in the city, I think I might stay with 14T.

J found when I di go + 1 on my front sprocket on my 300 R... the Speedo seemed spot on..yet the ODO when observed in a measured KM distance was inaccurate (low). So of course mileage was less that it actually was...and calculating L/KM..or MPG (Imperial) was a bit off too. None the less I did like the change.
I hadn’t really thought about the mileage calculation until kiwi rider brought it up, but I’ll live with that. I check my fuel consumption often, but just as a way to monitor engine health. After three years, I know pretty much exactly how much fuel it really uses (typically 3.2-3.4 L/100km). I will check it now just to get a conversion to actual.
 

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I always converted my L/KM to MPG (Imperial)...old school as I was brought up on Imperial system as far as mileage goes. I constantly got a little over 90 MPG if I rode (like a Granny:D) between 80 KMH to 90 KMH...
 

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Discussion Starter #11
I am happily metric with everything except my own height and weight. In the real world, L/100km tells me how much it will cost to go somewhere. MPG tells me how far I can go on what’s in my wallet. When I run away, I will switch back to MPG. :)
 
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