Please Help! 2001 gsxr750 cannot go above 8k rpms!!!(c28)

[socalgsx-r750]

So I have been chasing my tail for a while now trying to figure out what is wrong with it, when it isn't under load it can rev up to 8k or so, but when under load i can barely get above 6-7krpms. Here is what i've done so far...

1.New spark plugs w/ correct gap
2. Cleaned and oiled air filter
3.TB's synced
3.valve adjustment
4.new fuel filter/rebuilt fuel pump
5.cleaned fuel injectors
6.new fuel line/checked for kinks

The STVA cables were removed and valves are sprung open, think the unit itself is shot, but before i go spend a ton more money would like to know if i'm heading in the right direction. Any input would be greatly appreciated!!! Wouild be nice to ride a fully functional bike again.

[Samantha750]

You have a code, c28, did you try searching?

http://www.gixxer.com/forums/showthread.php?t=308727

[socalgsx-r750]

I'll check it out right now thanks!

[Samantha750]

If that doesn't help, either PM thegeek or search for c28 error code, likely it will need replacing or soldering. Lots of threads about it though.

[dan uk]

Either get some used, fault free secondary throttle bodies from somewhere like ebay or strip and re-solder the dodgy connection yourself. I think it includes drilling out a few rivets for access. I'd remove them and take to a shop to do the fix for you if you don't fancy.

I'd source some replacements though

[kevin.g]

Its easy to resolder with basic skill. I'm no surgeon by any means with a soldering iron and I was able to do it

[socalgsx-r750]

ok so i took apart the STVA unit, cleaned up the insides a bit and made sure there was good contact, it did its open/close cycle when i plugged it back in...but only that one time, now it will not do it's cycle(was not doing it before i opened the (STVA)

[socalgsx-r750]

have not resoldered the connections yet, will try now

[socalgsx-r750]

connections resoldered, but no response from the unit still, probably shot? and it could be directly related to my rpm issue correct? tired of messin with it proly will just get a new one if its the proper soluition, i've heard of people overriding it, is that possible?

[kevin.g]

http://www.motorcycleforums.net/foru...or-defect.html

This link is for a 2004/2005 model but the STVA may be the same on your bike? I'm not sure

It's the write up I used and it helped me get the job done

[kevin.g]

Also:

http://www.youtube.com/user/matyc13

This guy figured out how to bypass the STVA, he has the same bike as you. If you do some google research you should be able to figure out how to fix or work around it. Good luck.

[fastboatster]

stva on 00-03 750 is different, pm geek, he found out that excva (exhaust valve) motors from many newer gsxr would work. geek said that on 00-03 bike solder doesn't fail, it's the motor itself, apparently, brushes wear out eventually.

[kevin.g]

Sorry I misinformed you