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Old 03-25-2010, 04:51 PM   #1
adonets
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Question Full throttle problem

I have a Sachs MadAss 88cc bike, 50cc engine with some performance parts on it. The bike is 1 speed.

My problem: when throttling anywhere from 0-95% of the throttle's capacity, it is perfectly fine, accelerates as it should and everything works well. However, when I absolutely crank it to 100% to where the throttle cannot go any further, the engine starts to act funny, and would decelerate in 0.1 seconds and accelerate in that time again, so sort of like have a very jumpy, vibrating speed. It's not like it would decelerate over 3 seconds then accelerate again, it would do this in a fraction of a second.

Is this normal? Am I ****ed? I hear from a guy that this could be a problem with my carb.
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Old 03-25-2010, 06:17 PM   #2
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Sounds like your getting to much fuel threw to small of a main circuit or mainjet, if your needle is adjustable you may beable to accomplish the adjustment with your current mainjet, if not you'll probably have to go a size bigger on the mainjet. Good luck.
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Old 03-25-2010, 06:18 PM   #3
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Sounds like someone is on the rev-limiter........
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Old 03-26-2010, 08:51 AM   #4
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Originally Posted by The_AirHawk View Post
Sounds like someone is on the rev-limiter........
Could be. How do I get off from it?
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Old 03-26-2010, 09:04 AM   #5
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The rev limiter is designed to prevent you from over-reving the motor. When the RPM's exceed the target range for that gear, the limiter kicks in to prevent you from going beyond that point & potentially causing engine damage.
Try leaving the bike in a lower gear (anything other then top gear) and keep accelerating, you'll notice the power dies off and the engine seems to "miss". If thats the same symptom your getting at higher speed in high gear, the limiter is preventing you from accelerating beyond that point. You can also just open the throttle in neutral & the limiter will prevent you from overreving it, the sound will be there but you won't experience the power loss.
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Old 03-26-2010, 09:07 AM   #6
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You said single speed engine, sorry. Your probably already at the top speed the bike is designed to go. You can disable the limiter, but your asking for trouble if you do.
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Old 03-26-2010, 09:55 AM   #7
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An 88cc bike with a 50cc engine.

Maybe you should get a bigger bike.
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Old 03-26-2010, 10:03 AM   #8
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Is it a two or four stroke? If it's a two stroke, and you have performance parts on it (chamber, ported cylinder, etc) you will have to either raise the needle in the slide to get more fuel in the motor at full throttle, or get a bigger main jet.

If it's a four stroke, throw it away.
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Old 03-26-2010, 03:12 PM   #9
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Quote:
Originally Posted by Kenneth_Moore View Post
An 88cc bike with a 50cc engine.

Maybe you should get a bigger bike.
First, learn to read.
Second, learn to use your head; your comment makes no sense.
Third, and lastly, you did not answer or even touch on answering the topic designated to the thread. Go to 4chan if you want to keep being an idiot.
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Old 03-26-2010, 03:16 PM   #10
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Quote:
Originally Posted by mscuddy View Post
Is it a two or four stroke? If it's a two stroke, and you have performance parts on it (chamber, ported cylinder, etc) you will have to either raise the needle in the slide to get more fuel in the motor at full throttle, or get a bigger main jet.

If it's a four stroke, throw it away.
It is a four stroke. It is new. Why am I throwing it away? Please elaborate on your suggestion.
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