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The 700D has a 39T rear sprocket and the 700A has a 43T sprocket. Has anyone with the 700A considered installing the 39T sprocket. You would have to remove a couple of links. I haven't had the trany sprocket cover off so I don't know if it would accept a sprocket with an extra tooth. You would lower your r's and improve gas milege. The engine has plenty of power and torque to handle the swap. The roller chain sprocket setup is tough and easy to work with,not to mention, its economic. For my riding around here in central Ky. the factory combo works real well on my 700A. Just thought maybe some of the speedsters might be interested.
 

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When I get my bike I will be swapping it out. Ive had the sprocket sitting here for a while now. You don't need to remove any links. This set up is not for speeders, but for just the opposite.
 

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Just remember the two models have different internal gear ratios.
The primary reduction is 71/41 which means the crank turns 1.731 for 1 turn
of the transmission input shaft for standard and 73/38 for auto or 1.921 revs for 1 transmission input shaft turn. So engine turns faster on the automatic.
Gears 3 4 5 6 are the same ratio and 1 & 2nd on standard are lower geared (higher ratio)

final reduction is 43/16 2.687 rear sprocket/front sprocket standard and 39/16 2.437 for auto.

changing rear sprockets is about a 10 percent change roughly so you could say at 4000 rpm at 65mph would drop to around 3600 at 65 miles per hour.

remember the torque curve (not found in the service manual). You have to consider will the engine be running at the rpms less to pull any given speed. You say it has plenty of power. Ride around 400 rpms less in 6th gear and twist the throttle and see what power you would have before changing it. Just a suggestion.
 

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I'll not swap a perfectly-good sprocket but when my chain and/or sprockets wear out, I am seriously considering going with a smaller rear or larger front if I can find it for the standard model, however, a quick search has shown me only higher ratio choices so far, so I don't even know if it's available for this bike.

There are some downsides to swapping that I am considering though. First; this is the first vehicle I've owned in a long time that has an accurate speedometer. This is a nice feature to not have to estimate how fast I'm really going. Also, I like to track my mpg consistently. Changing one of the sprocket sizes may complicate things and cause me to have to guess at things. I don't own a GPS and don't really need one, since I rarely travel, so I rely on the info. on the bike to do quick calculations. Secondly; I'm able to barely use 6th gear riding through one town daily without speeding too badly or lugging the engine at or about 50 mph (going through 40 and 45 mph speed zones). If I'm running in higher gears, at least in city riding, I'll be using 5th gear more often and not helping the RPM situation in those circumstances. I'm still undecided at this point, but I would like to be running under 3,000 RPM instead of over 3,000 RPM at my normal 57 mph speed for the 20 mile stretch I make each day on a two-lane highway. And then part of my route, I ride around 63 mph, and the RPM would be lowered then as well. I don't do alot of passing or progressive riding in the rural area I live in (I'm used to a 100 horsepower car), so I don't think a performance drop in throttle response in higher gears would be a deterrent for me making the change personally.

I did not know this fact about the larger sprocket on the D model. If I had the dual clutch, I'd definitely be swapping when it became time as this seems like a good way to put the D model on par with the standard with respect to mpg, or closer anyway.
 

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OEM sprockets work great for me. Heck, gas milage is great, I have S mode and paddle shifters ... fantastic.

If (don't think the front sprocket area has the room) they ever come out with a belt drive replacement, I would do it.
 
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