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Discussion Starter #1
I've got stock 14/50 sprockets, the bike is finally running right, and the bike tops out around 73 mph. It's horsepower limited at that level, instead of rpm limited - because I can faster if running downhill.



If I change to 14/47 sprockets, which should theoretically increase speed while decreasing torgue - would the bike have a higher or lower top speed?



I apologize if this simple question has already been answered; I searched and founds tons of info - everything except whether the top speed would increase or decrease.
 

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Should not change the top speed, it would just lower the rpms. It will give you a little bit more speed in first gear, meaning you shouldnt have change gears in an intersection. That is why many people get 47t rears. You may be able to go a little faster downhill...?



This is just my understanding. Someone else may jump in with a more conclusive answer.
 

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I've got stock 14/50 sprockets, the bike is finally running right, and the bike tops out around 73 mph. It's horsepower limited at that level, instead of rpm limited - because I can faster if running downhill.



If I change to 14/47 sprockets, which should theoretically increase speed while decreasing torgue - would the bike have a higher or lower top speed?



I apologize if this simple question has already been answered; I searched and founds tons of info - everything except whether the top speed would increase or decrease.
Like you said the speed should theoretically increase as long as the torque is not required to maintain that speed, such as an uphill climb or a headwind. I have not gone down in the rear sprocket count but I would think a 3 tooth drop would be fairly difficult to notice as each tooth varies the speed by approximately 1.5 mph, I believe. The torque loss may be more noticeable as the engine doesn't have a lot to begin with and every little bit counts. It sounds like you have the bike running real well to obtain 73 mph, not sure I'd want to go any faster. I'm sure there are others on this forum that are running the 14/47 combo and could be a little more specific with the info.
 

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Discussion Starter #4
I picked the bike up a few weeks ago, and top speed then was 62 mph. Going thru the carb fully, changing to 132 jet, shimming the needle .040" has it running a touch rich now.

I had ordered a smaller rear sprocket when I ordered the carb parts, but now I'm wondering whether to install it or not.



If changing the sprocket will add a few more mph to the top end, I'll do it. If changing the sprocket will lower the top end due to reduction of torque, then I'll be happy with where I'm at.
 

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I have a 15/47 on my machine, it works well but I still only get about 65-67 mph out of it. This may be due to a failing CDI though, it will be replaced next month and I will test further.
 

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I've got stock 14/50 sprockets, the bike is finally running right, and the bike tops out around 73 mph. It's horsepower limited at that level, instead of rpm limited - because I can faster if running downhill.



If I change to 14/47 sprockets, which should theoretically increase speed while decreasing torgue - would the bike have a higher or lower top speed?



I apologize if this simple question has already been answered; I searched and founds tons of info - everything except whether the top speed would increase or decrease.
I have a stock tw and I have a top speed of 72. Ive thought about changing some things around to reach a higher top speed and lower my rpm's but have dicided its perfect the way it is. I dont want to hurt first gear cause i love the granny gear while climbing.
 

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RingSteel,



For the most part I think your question has been answered, but thought I'd mention my ride yesterday, in regards to gearing. I have stock gearing and my TW runs about the same as Brent Morley's, mentioned above. I also do quite a bit of steep climbing off-road, thus I want to keep the stock gearing for that.



Anyway, yesterday it was very windy here (30-40 mph). Have hills too. With the stock gearing I could go just as fast as I wanted - with the wind (65-70mph range). In the crosswind I could barely get too, and hold 55 mph. Nothing over. Against the wind, well it wasn't good, 50-55 sometimes, but usually 40-45 when I went up a slight incline.



Moral of the story is, I think if you drop to a 47T rear, your riding comfort may improve with less rmps and buzz, if it's flat and no wind. But you will find yourself in 4th a lot (maybe 3rd), when going uphill or into the wind (or crosswind) with a 47T.
 

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Anyone feel compelled to sift through sprocket chain posts and post and pin the result? I can try to do it when I get some time. Off to work now though.
 

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I had changed to a 15/50 setup and driven them into the grave / no kidding I cut 2 links off the chain just to get 2 more months out of them. The 14/50 setup leaves you wanting a 6th gear, the 15/50 reduces the revs and takes longer in each gear and you actualy have a top gear as well. I'm sure there are many setups to suit drivers various styles but you have to check out at least 2 of them yourself to find one that suits you.

It's a bit of a rigmaroll because you have to drain the oil and remove the foot rest, the gear lever, the gasket can be worn out from too much work and you must be careful not to pinch the cables from the magnito, but it's worth the effort.

rgds

Alan
 

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Haha. Touche'



Actually if anyone sees this in their "search" on the topic the search will reveal enough information to make an informed decision regarding sprockets and chains. I'll add the advice though that I received from the bear.



Any o'ring chain will do and good advice is to do sprocket and chains together.
 
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