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Discussion Starter #1
Doing some research on gearing and the effects ( good and not so) of changing sprocket sizes to change gearing. I can't see the point of gearing down to improve acceleration. Any more acceleration and the 700 will flip, my guess.

Does anyone have any thoughts or experience with gearing up? Just a smidge, nothing drastic - say +1 to front sprocket.

Benefits as I understand (total newby) are lower revving, longer gears and maybe slightly better fuel economy. My thinking is that can't be bad for the longevity of the engine.

Yes, I know I've winged about the lower HP of the Australian engines (compared to our US, CAN, EU cousins)....but it's probably still enough. There, I said it 馃榾
 

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Lower RPM doesn't necessarily equate to better fuel economy if it causes the engine to work harder to maintain the same speed. Usually the engineers will gear a machine to be making the best power at regular HWY speeds, if it's making the best power, it's probably the most efficient part of the power range. Raising or lowering the engine RPM may actually reduce the power efficiency, therefore reducing fuel efficiency at the same time. You can try it but I'd work with the rear sprocket rather than the counter shaft sprocket. I'm not really sure about the XSR but many times it's really hard to increase the size of the countershaft sprocket because of clearances at the engine. Again, you can certainly try but check the countershaft sprocket for room.
 

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Discussion Starter #3
Cheers, FD. Appreciate your thoughts.
The lack of responses on this is telling, I suspect.
Doesn't inspire me to make changes, just sounding out the logic.
 

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I'm looking at stepping up a tooth. Since the power comes in strong around 3500 it shouldn't be a problem pulling a tooth more on the front. It was one of the comments in the Motorcyclist commute test on line. The fact that the bike is spinning a bit at 65-70 mph and could easily pull a taller gear.

I think it's geared as it is for performance, after all it is known for being rather easy to carry the front wheel in at least the first two gears.

I would guesstimate that the prime operating rpm for efficiency is probably between 3500-4500 rpm and that if you are in a taller gear and drop below 3500 you are better off to downshift for fuel economy. I learned about this when selling Hondas. We had Gold Wing riders complaining about poor gas mileage and shuddering when accelerating. We learned these guys were running in the 2000-3000 range. The response from Honda was that the most efficient range to run was 3500 to 4500 rpm, even if it meant dropping to fourth.

So a friend and I did just that when we were riding two up from Niagra Falls Canada to New Philadelphia (just south of Canton) Ohio. We rode standard Wings, no bags or fairing, but did have boxes and soft bags, his was a GL1200 and mine a GL1100. We were riding the back two lane highways in the Appalachian Mountains of west Pennsylvania. We would keep in the 3500-4500 rpm range even if it meant downshifting. We both pulled within a mile or two of 50 mpg. All considered we were in 4th a lot on curves in the mountains, and occasionally 3rd on the tight stuff. We didn't baby the bikes by any means, but still hit 50 mpg.

I'd bet the XSR could easily pull a tooth higher on the front... but less wheelies... BOO!
 

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Discussion Starter #5
Hey Klx, thanks for that, man. I am learning heaps thanks to the collective knowledge on this forum. Much appreciated.
 

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I did that same thing on my Zephyr 550 going up a tooth. I figure I usually cruise around 60-70 mph, so gearing to have it in prime rpm at 50-60 didn't make sense.

I have a gearing comparison spreadsheet I made up some years back. If you can get the tooth count of the transmission gears, sprockets, and tire diameter. It is an excel sheet and I have a google sheets version that I am not too sure if it works, the formulas may or may not transfer. If you are interested PM me. I can't load the spreadsheet here.

It indicates mathematically calculated speeds in each gear based on the RPM variable value. So I was able to compare dual sport tires to street tires when I was considering doing a set of supermoto wheels and how much difference the speeds would be if I used the same tooth count on each tire. The sheet has two charts to compare rather than having to remember everything. Cells are labeled. Six speeds possible.
 

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I just changed chain and sprockets. I went up two teeth in the back to 45 and left the front sprocket at 16. Acceleration is improved without excessive rpm's at highway speed. It is much more fun to ride now for sure. Easily wheelies in 2nd gear. I lost about 3 miles to the gallon though.
 

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Discussion Starter #9
I just changed chain and sprockets. I went up two teeth in the back to 45 and left the front sprocket at 16. Acceleration is improved without excessive rpm's at highway speed. It is much more fun to ride now for sure. Easily wheelies in 2nd gear. I lost about 3 miles to the gallon though.
Thanks guys.
KLX, appreciate your detailed comments.
 
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