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What is the best way to lower my rpm's??

Mobes

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DeKalb, Il
I have a '76 CB750F SOHC that I bought about 8 or 9 years ago. I installed air pods, and swapped the original muffler for something louder and smaller. I had the carbs rejetted for the modifications. Since the engine is now breathing easier, i have noticed that the rpm's seem to be quite a bit higher than they were before the work was done. At 65 mph the engine is at 5k rpm's, and at 100 mph the engine is just over 8k rpm's. 4 years ago, the chain broke and punched a hole in the case. I have since fixed it, but I don't remember what the rpm's were before the modifications were done to the bike. I want to get my rpm's lower while cruising, and I'm just not 100% sure on how to do that. I thought maybe changing the rear sprocket to a bigger size would help, and then I thought changing the front sprocket might help. At this point though I'm just not sure of the best way to lower my rpm's. The bike does need some work which I will be doing over the next year, slowly as i want to ride it as much as i can. Any and all advice on this is much appreciated. I know i may have to sacrifice low end performance, but I'm okay with that. I like having fun in the top end, and saving some fuel would be nice too. Thanks in advance.
 
Non of the things you have done can affect the rpm at a given speed unless your clutch is slipping. The only way you can lower rpm at a given speed is different wheel diameter or gearing change. To lower cruising rpm you need a smaller rear sprocket or a larger front sprocket.
 
Well, i know for a fact that my clutch is not slipping. I have been doing some research and came up with exactly what you are saying about the sprockets. Thank you for taking the time to reply.
 
Part is impression, anytime you ever open up the exhaust they always sound like they are spinning faster, it being a noise perception thing.
 
That is true. Perception is influenced greatly by sound

If the rpm is truly higher then what it was and the gearing is the same then your clutch is slipping whether you believe it or not, no way around it.
 
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