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Discussion Starter #1
I don't care what anyone says. I have now rode over 100 miles on my V Star 650 with the AIS bypassed and no other modifications whatsoever.

I have MORE power. It is very noticeable in first gear, but I feel it in 2-4 as well. The gears have been extended, I can comfortably stay in lower gears longer. Acceleration in 1st gear is a huge improvement.

A lot of people say the that bypassing the AIS won't increase power. I think the reason most people feel this way is because they bypassed the AIS after doing exhaust and intake upgrades and re-jetting their carbs.

I did the opposite. I bypassed the AIS before I started all the other stuff.
 

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ok i will bite on this. :)

How did you do the bypass? Did you put the plug in the head or just the rubber tube?

If you were to put the plugs in the head in theory it could help with the exhaust gas pulse. The chrome tubes that lead to the ais module bleed of some pressure the placement is not great since it is so close to the exh valve.

If you just plugged the rubber tube i cant see any power increase.

I do have my removed and heads are plugged my bike is not super modified the only difference I noticed was less high rpm back firing
 

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LOL.....there have been hundreds of 1100 riders that did exactly what you did. No increase in performance....all you did was cut off a small supply of air to the exhaust pipe. There is nothing there that can add more HP...better gearing....or anything else.....unless you had something totally messed up in that area to start with.....like a vacuum leak. In that case, yes...you'd get back to stock performance.

But if you feel like it is faster....that's cool. If you want to find out for sure, have it dyno'd and tell us how many HP over 55 it is.....
 

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I ride a 1300 Deluxe and have never had a power issue. I doubt that I have ever maxed it out. The bike is stock except for lights, horn comfort mods etc. I don't think I will ever change anything for the sake of more power or, "a better sound." I just like to get on and ride. 11,000 miles so far this summer and if it weren't for snow and below zero temps here in Oregon, I would ride till my legs fell off.

My snowshoes are looking so boring this year !
 

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Discussion Starter #6
I'm sure the 1300 is louder than the 650.

I never intended to want to change the pipes when I bought it. However, I can't even hear my own bike at speeds over 45.

I got the new pipes on and the carbs re-jetted last night. Just got to put the gas tank back on tonight and carb sync.

I ride a 1300 Deluxe and have never had a power issue. I doubt that I have ever maxed it out. The bike is stock except for lights, horn comfort mods etc. I don't think I will ever change anything for the sake of more power or, "a better sound." I just like to get on and ride. 11,000 miles so far this summer and if it weren't for snow and below zero temps here in Oregon, I would ride till my legs fell off.

My snowshoes are looking so boring this year !
 

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Removing the AIS was a good thing for the new pipes. If you have no cat, there's no need for the AIS anyway. The performance change MAY have been because the AIS was exaggerating a problem and removing it "fixed" it or at least made it better. If you start getting excessive popping you may want to check for air leaks. Rejetting helps for sure but now that you have less back pressure any leak can suck air into the exhaust and cause popping.
 

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Discussion Starter #8
I put the pipes on Sunday night. re-jetted Monday night. Today I put everything together, tweaked the idle and the carb sync. It ran and sounded awesome. Tried to take a picture to post, but the battery in the camera was dead.

I got a carb sync tool on ebay for $32. It is two vacuum gauges mounted to a piece of sheet metal with two hoses. Once I figured out how it was actually supposed to work (the real secret to making it work was not including in the instructions) , it was simply to tweak the carbs.

I'd like to tweak the air mixture screws with an exhaust gas analyzer. Apparently they stopped making cheap handheld ones in the late 80s.
 
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