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With A LOT of tuning you can bring it back some, but it will always be different with the removal of the EXUP. Like everyone has said, a carbed EXUP bike really needs the EXUP valve. What you are now running into is so much valve overlap that exhaust gases are reentering the combusting chamber then moving on the way. You will gain top end HP to the tune of a couple ponies, but the low / mid range is pretty well what it is going to be. I learned this in 2000 when I put a full system on my FZR. Takes a while, but you'll get used to it.
 

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Moderator - In Memorium
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what about degreeng the cams or using high lift ones,will it do any good?
Yes. According to the things I've learned through playing with the EXUP engine you can advance the intake some and retard the exhaust to accomodate working around the overlap issue that necessitated the EXUP in the first place, but ultimately what you may end up with is back to stock or there about performance levels. JAYSTENSEC4CYL gave you tuning advice that will work for the R1 of your year. Trust what is proven... or you can spend hundreds trying to find out the same thing,
 

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bigger pilots for an overly rich condition below 4k rpm?
That and the 41 mm FCRs... :confused:

Honestly, I'd stick to the EXUP on the carb'd bikes if not on the race track. You understand the tripple carburetion problems inherent with large cam overlap, but some people don't want to hear it when they are shopping for mods. I regret putting the full system on my FZR. I spend too much time every year tuning that bike, and having to adjust my riding to how it wants to deliver power in the low/mid range compared to how it did. :(

You hit the tune on the head earlier. Ivan did it well. I'm thinking about calling him since my carbs are off the bike right now (only put about 6k on this thing this year.... :chair: it's way below par right now)
 
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