98 SRX bogs at WOT

[spencer2626]

PLEASE HELP
I am trying to help my nephew with his 98 SRX he really wants it to run ...
the thing starts and idles fine, and revs up to about 5000 rpm, all seems well, until you go past that, it bogs and runs like crap..every now and then it picks up and flies, but rarely, we changed the reeds to carbon fibre, when we found a bad reed that was causing it to run only on outer two cylinders -but it was doing this before too, although now it runs on all three fine up to 5000rpm

also...on the stand, it will load up the same, and then backfire unburnt fuel..

pipes, and silencer are not plugged....ideas? it seems rich or electrical. its not starving for fuel

if you need more info to help us please post the question

 

[mrviper700]

couple questions:
1.) have the carbs ever been cleaned on it?

2.) have the power valves ever been cleaned on it?

3.) does the water temp light blink 3 times when you first start it and does it flash at all when riding the sled?

 

[yamaholic22]

yup sounds like a powervalve problem or a possible clogged main jet

 

[tommyt5078]

Mine did soemthing likes this the other year, it ended up being the boot that goes on top of one of the spark plugs, seemed to idle and run fine tell I hit the gas hard!!!