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I recently took my carbs off and cleaned them. Now that everything is back together I have noticed a huge loss of power and top speed. I can only get up to around 60mph in 5th gear with wide open throttle. Any ideas what’s causing this? I also got rid of the goat’s belly and replaced my stock mufflers with ones from a Harley Dyna. I don’t know if that effected anything.
 

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I had a similar sympton when I lost my rear cylinder.

Might want to make sure you have spark at both cylinders. If not, go back and check all electrical connections.

If not spark related, make sure that both gas lines are connected correctly to the petcock. Try loosening the drain screw in each carb to make sure that gas is getting into each carb.

It sounds like you are running on one cylinder for either ignition or fuel reasons.

Jon
 

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See if any of this helps...

The problem went like this. Twist the throttle and you begin to move out, then as you continue to twist the throttle it has less and less effect. As if it is starving for fuel or the throttle is not working.

Well I had a hunch I knew what it was. When rebuilding the carbs I had a problem with the Vacuum piston / diaphragm assembly. The diaphragm did not want to seal properly but I thought I had them in right. Nothing to do but pull the carbs yet again! Well that was part of the problem. Another thing was the spring seat for the needle jet. You need to pay attention to the hole in the bottom of the Vacuum piston / diaphragm assembly, there are two. One is for the needle and the other hole is to allow for air pressure differential, which is what moves the diaphragm up and down. I am not sure I checked this before reinstalling them the first time.

Once I fixed these, the bike runs like it should!

If you rebuild or clean your carbs pay particular attention to these areas. I used a very small amount of gasket sealer to help hold my diaphragm in place during instillation.
 

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Check to be sure that the needle is UNDER the spring holder and not thru it otherwise the needles will be too high.
 

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I recently took my carbs off and cleaned them. Now that everything is back together I have noticed a huge loss of power and top speed. I can only get up to around 60mph in 5th gear with wide open throttle. Any ideas what’s causing this? I also got rid of the goat’s belly and replaced my stock mufflers with ones from a Harley Dyna. I don’t know if that effected anything.
You'll lose some low-end torque with the removal of the goat's belly, but that shouldn't affect the top end. Looks like ya might need to pull those carbs again. :(
 
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