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A little history...08 1100 with Hypercharger and new full Cobra exhaust. Just re-jetted to 120 main rear, 122.5 front, #20 pilot's, 3 turns out PMS, 2 shims on each needles and Emulsifier mod. Ok...just did a dyno run and it is showing the front cylinder is pretty lean at lower RPM then goes rich at higher RPM, rear cylinder seems relatively consistent. I'm new to messing with carbs so wanted to ask if might work to go bigger on the pilot to correct for lean condition at lower RPM then reduce main for rich condition at higher and leave rear cylinder as is??
 

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the hypercharger is a ram air intake

unless you have 100 mph air hitting the front of it on the dyno, its not going to run the same as it will on the road

and its known for being difficult to tune for low rpm, its designed for racing at high speed
 

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Discussion Starter #3
the hypercharger is a ram air intake
Good point!! didn't think of that. Overall the bike is running better post re-jet incl. smoother shifting, no decel pop etc etc, I'm just thinking if it seems to be an improvement then leave alone. I was just curious to see what it would show on a dyno and this "issue" with the front cylinder showed on the graph
 

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Super Moderator "Loose Nut"
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Here's some info on hyper chargers and dyno tuning.

First of all let's stop to consider the fact that it is a RAM AIR INDUCTION device. If you try to tune the thing on a Dyno, you will get miserable results, unless you Dyno is in a wind tunnel. Short of that you would need to in some way provide accelerated airflow to the Hypercharger inlet, at a velocity that would match the speed you want to tune it for. The fact is, you really can’t use this method as static Dyno tests will only give you a fairly clear picture of the HP and Torque of a bike that is not going anywhere, but just spinning the hell out of it's drive train with an artificial load on the drive wheel.

Follow this link for more info, about half way down.
https://sites.google.com/site/vstar1100kb/home/5-modifications/4-intake-modifications

The hyper charger is more of a cosmetic item rather than a performance item. If you can get it set close, call it done.
 

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I have to agree with the other members, if you thrifty the principle behind it, it’s kind of similar to the ram they used on muscle cars back in the day. Before I relocated to East Tennessee I had a buddy that bought one for his bike. He couldn’t get it to idle smoothly, he changed it out for an open air filter kit and it purred like a kitten.


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Discussion Starter #6
He couldn’t get it to idle smoothly, he changed it out for an open air filter kit and it purred like a kitten.
I am finding the idle is not as smooth, also cold starting is a little more "finiky" but acceleration and on highway performance is better with 0 decel pop. The Hypercharger was on the bike when I bought it but now having been educated on it's issue's...I am tempted to switch to a pod set up. Also wishing I asked before spending $$ on the dyno lol...but at least I know it pumps out a whopping 53hp :cool:
 
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