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All right gentlemen I finally pulled my ECU and sent it out to Danos today. I'm going with a Decat, slip-on and stock air filter. I've been searching through some of the threads on here and came across a few about bumping the RPM limiter up to around 12200 but I have not seen any discussions about maximum safe RPM for these engines. I really don't flog mine up to redline too often and I haven't hit the limiter yet even though you really can't see the tach on these while you're trying to watch down the road at maximum thrust. LOL so does anyone have any idea what these puppies will take.
 

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All right gentlemen I finally pulled my ECU and sent it out to Danos today. I'm going with a Decat, slip-on and stock air filter. I've been searching through some of the threads on here and came across a few about bumping the RPM limiter up to around 12200 but I have not seen any discussions about maximum safe RPM for these engines. I really don't flog mine up to redline too often and I haven't hit the limiter yet even though you really can't see the tach on these while you're trying to watch down the road at maximum thrust. LOL so does anyone have any idea what these puppies will take.
I read some years ago that even a single instance of valve float reduces the strength of the valve spring by several percent, which means the spring is no longer capable of supporting the rpm it was before. And the spring loses more strength every time the valve floats.

Can't remember where I read that, but that was the gist. Ever since reading that I've vowed to avoid valve float like the plague. IMO, exceeding the factory redline on a stock engine just isn't worth the risk. The potential consequences (which are numerous and expensive) outweigh any benefit.
 

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the stock gsx-s valve springs are 36ft lb seat pressure and max lift of valves is 8.7mm, this in comparision to gsxr1000 k5 spec of 28 lb seat pressure and max lift of 9.5mm plus their rev limit is 12500rpm, though there valves are titanium.

the stock gsx-s powerband is in decline before 11500rpm so they set rev limit early, ive set mine at 12500rpm, no worries with valve float, the stock conrods are steel which actually stretch less than the titanium gsxr items.
im building another hi performance cylinder head from a gsxrk8 item to install on my gsx-s, it will be running hi lift race cams (9.9mm/255 dur) and with raised rev limit to 13500rpm, though i will be using 45lb valve springs, so yes the rev limit stock can run at least 1 thou higher with no problem
 

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I have my rev limit set at 12,400rpm and hit it regularly on track without any issues, the engine is capable of running at 12,500rpm comfortably without letting go.
 
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