1999 GSX Limited lost power (5800 RPM)

[cbetts07]

We have two 99 GSXL's that were running decent, but not great (6500-6600 RPM). After doing some reading on here, I changed the spark plugs and cleaned the raves. Now, one of them runs about 6600-6700 rpm, and the other one runs terrible. The bad one runs 6000 at best, and usually closer to 5700 - 5800 rpm. If i hit any waves, it drops back to around 5000. We thought we did something wrong when re-assembling the RAVES or got a bad spark plug, so we swapped both the raves and spark plugs between the good and bad skis. No change, the good ski still runs good and the one running poor continued to run poor. We also swapped the computers, so that is ruled out as well. It also spudders out of the hole, but it has always done that. What should I check now?

thanks

 

[gsxgtxman]

Do you still have the gray fuel lines? Done a Compression test?

 

[cbetts07]

It has the black fuel lines. I'll have to do some research regarding the compression test. However, my other ski that runs good does have the grey lines. Should I change those out?

 

[timmyboy76]

could be a bad/tweeked WR (water rugulator), rich mixture or stick'n raves...Last time, carbs were messed with?

 

[cbetts07]

according to the dealer, the engine was newly rebuilt. We had it out probably 3 times before it started acting up.

 

[timmyboy76]

recheck compression,m pull the raves ,and the rave look'n thing on the muffler, undo that, and make sure the fitting aint plugged up.

 

[cbetts07]

hey guys thanks for the reply's. My stepdad said that since it seemed to lose power the longer the throttle was held down it couldnt be a compression problem. I just wanted to see if you agreed with this before i buy a compression tester.

 

[cbetts07]

I haven't done much since I posted this, but I wanted to make a couple of points about what the ski does. We had it out again today after draining the fuel and putting in fresh. It will go up to 6500 or 6600 rpm at full throttle initially, but as I accelerate, it drops off until it gets to around 5700 rpm. The 6600 rpm just lasts a couple seconds before it begins falling back. The other strange thing is if I high some waves, it loses power and falls back to 5000 or sometimes less. Does this sound familiar to anybody? I noticed a couple of the short lines going between the carbs are grey, so I'm going to pull the carbs, change those lines, and clean the fuel filter.

thanks

 

[cbetts07]

One more thing i wanted to point out. I read on here that a leak in the head pipe/exhaust manifold will drop 1000 rpm. When looking at the engine, I've noticed 2 of the allen bolts holding the head pipe on are loose. I will obviously get those tightened up, but does anybody think that could have caused a problem?

thanks

 

[cbetts07]

Since one of the loose bolts was the hard to reach one, we went ahead and removed the head pipe to make it easier to get to the carbs. We cleaned the filters in the carbs, and also replaced grey lines. Before I put the head pipe back on, is there anything I need to do to look for a leak, or should it be fine as long as I make sure everything is sealed and tightened up? I'll also be sure to do some reading and check out the check valve and solenoid for the raves.

thanks guys