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Old 04-01-2014, 06:15 AM
dylanriha dylanriha is offline
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Lightbulb MOAR POWER RAWRRRRR (questions)

Recently built my "80cc" motorkit onto my huffy beach cruiser, it gets up to 30 on flat land which is insanely fast for me (I get scared of the wobbles lol ). I was told that if I remove the cap on my muffler that I'll get more power is this true? Also I was looking at aftermarket parts and they have a expansion chamber or the "poopoo" muffle (really long one) will either of them help? I'm also wondering how those are installed. My neighbor has wielding equipment if needed. thx
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Old 04-01-2014, 10:29 AM
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2door 2door is offline
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Default Re: MOAR POWER RAWRRRRR (questions)

I'm not understanding you. If you are uneasy @30mph, why do you want "more power"?

Don't remove the muffler end cap. The performance increase will be negligible and you won't be doing your neighbors or the hobby any favors by riding an annoyingly loud bike. Those who advocate removing the end cap and claim big power gains are only fooling themselves. It sounds faster, so it must be faster. Not true!

You might want to explore a smaller rear sprocket if a higher top speed is what you're looking for. Also tune the carburetor by experimenting with jet sizes. The expansion chamber exhaust is another area where you can gain some power.

Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"
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Old 04-04-2014, 11:54 AM
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mapbike mapbike is offline
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Default Re: MOAR POWER RAWRRRRR (questions)

Removing the end cap may add a couple MPH to the top end but thats about it normally, but one thing I do know for a fact...... is that if you will take the stock muffler and enlarge the port on the flange so that it is a closely matched as possible to the exhaust port on the cylinder/jug and then remove any baffling from inside the muffler and drill one or two extra holes in the end cap with a 3/8'' drill bit, you will see the same 1-2 maybe 3 MPH increase in top speed but the big difference you will notice is the hill climbing power, it will be the most noticeable change you will realize, stock exhaust really choke these engines down and kill the torque.

Now all this said, I agree with Tom if you live in the city or what we call live in town around here, you should try to keep a low profile and not run a wide open exhaust, it could get you unwanted attention from the fuzz and create a bad outlook on motorized bikes in your area, and that is bad for all of us....

the things I described doing are only good if you also have your carb jetted correctly, a very rich running carb will hurt performance no matter what else you do and in my opinion stay away from the pooper scooper pipes.... they will not add any performance... go with an expansion exhaust like the SBP Sick Bike Parts pipe if you want a fairly simple bolt on that will keep the noise down and stilll add performance.

I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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Old 04-04-2014, 06:07 PM
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Dan Dan is offline
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Default Re: MOAR POWER RAWRRRRR (questions)

Just to add to the above, but for just more power and some less top-speed. (if you want less top end) A simple and great bang for the buck is just a larger rear sprocket. It'll give a better start at stop signs and lights.

Just asking here, does your bike wobble at speed?
(Mine does but thats just me. literally, me. snork)

Another thing about removing the muffler cap. It works like a horn and is insanely loud for every one but the rider. I mean really loud.

But really, if every thing is how ya like it, I'd let it be. I know I will read about some mod or part and get all into it when it was not what I needed. But is great fun to tinker.
worst apocalypse ever
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Old 04-17-2014, 03:55 PM
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rogergendron1 rogergendron1 is offline
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Default Re: MOAR POWER RAWRRRRR (questions)

Check out the performance section of the forum it has tons of info and i made a whole thread dedicated to modding the stock muffler to gain power but it involves a lot of cutting and some welding and compleat removal of the cat to make a chamber where it oncewas
here to stay and compleatly insane ! deal with it lol
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