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Discussion Starter · #1 ·
Hey guys I posted this question to another member in another unrelated thread, but before I spend any money, I wanted other opinions.



I have a stock 78 Z50 that is very well kept. I'd like to increase the acceleration throughout the entire throttle range if possible while giving up as little on the top end as possible. I don't want to be doing major mods and want to change the appearance as little as possible. Another member suggested a larger front sprocket, but cautioned about the rpm ranges that I might get. What do ya'll think? If my current count is right, the stock sprocket (front) has 11 teeth. Recommendations?
 

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A larger FRONT sprocket will decrease acceleration. 11T front is as small as they come. So in order to increase acceleration (without any motor mods) you will have to get a larger rear sprocket. You will lose some top end though. No way around it. If you don't want to lose top end but still gain more acceleration...you have to mod the motor. I would suggest a bore kit/carb. Easy add on and allot more acceleration. Plus it doesn't change the look of the bike in any way.
 

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well you should just try to find a aftermarket exhasted. make sure they are good brands. if you cant find anything just mod the one you have now
 

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ive got a 78 z50 as well.You could get better accelleration and better all around power by adding a pipe and carb and possibly a different manifold and you should get a small but noticable increase in power.At that point you can play with sprocket changes while keeping the bike still mostly stock.If you everntually wear out the engine then youll already have the performance pipe a bigger carb ready to go and a small 88 top end kit wont cost you much more and your set.In stock form you wont get much out of a sprocket change alone as the 78 z50s are just slow even compared to my stock 88 z50.
 

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Discussion Starter · #7 ·
BAJAZBR said:
ive got a 78 z50 as well.You could get better accelleration and better all around power by adding a pipe and carb and possibly a different manifold and you should get a small but noticable increase in power.At that point you can play with sprocket changes while keeping the bike still mostly stock.If you everntually wear out the engine then youll already have the performance pipe a bigger carb ready to go and a small 88 top end kit wont cost you much more and your set.In stock form you wont get much out of a sprocket change alone as the 78 z50s are just slow even compared to my stock 88 z50.


Is it possible to quantify how much more power will be gained by the exhaust change? how about the carb change? how much more power?
 

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It would be difficult but ive have done a pipe and bigger carb to a few bikes over the years and it made a noticable difference.Bikes in general come from the factory for sale with economy and sound considerations a priority and built as such.These sacrifice power but are nessessary for mass production.
 

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I think you were referring to my response to your question in the CT70 air-screw-setting thread. I suggested a one-tooth-smaller front sprocket, not bigger.



But yeah, if you've got an 11 in front now, you don't really have room to go any lower in tooth count there. Might try a rear that's a couple teeth bigger. May have to get a longer chain if scooting the rear wheel forward on the chain adjusters doesn't give you enough slack. It might be enough, though; don't just run out and buy a chain until you try.



If your teeth (sprocket teeth, not mouth teeth) aren't symmetrical in profile don't just replace one sprocket. Better to get a whole chain-and-sprockets set. Putting any one of these components into service when the others are worn just wears them all faster. Should have mentioned that before.



If the teeth are asymmetrical, like saw teeth, or are curled over at the tips, or are worn to a real thin point, they're shot.
 
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