anything higher than 1/3 throttle no power

[jmcmotorsports]

well, rode the bike for the first time in a while today after doing some work on it and now it runs fine at just a little throttle but when i went to open it up some it felt like the bike had hit a rev limiter or something and just stops revving. its probably something stupid i know, but if anyone has an idea of what this might be would be awesome. thanks in advance for any help!

[thatkid]

How long was the bike stood idle/not used, weeks, months? what work did you do? It could be electrical or carburation.

Worn/fouled plugs or a weak spark won't fully combust the fuel/air mixture causing misfiring/hesitation @ high revs.

Rust in the tank will block the fuel filter, Stood for long periods the float bowls gum/varnish, blocking the jets. I've heard of mice building nests in the airbox, Blocking the element.

If you mean the bike revs to say 3k and stays there with no misfire, probably carburation. Running rich usually causes low RPM issues.

All of the above is guess work, Some more info would help. Hopefully it will be a simple fix, and you are welcome.

[jmcmotorsports]

it stood with ethanol fuel in the tank and possibly carbs i thought i ran them low though, for about 2-3 weeks. i put a new shock on it which makes the rear stand a little bit higher maybe 3 inches at the tip of the tail. i was kind of thinking that the carbs are starving of fuel because of the harsh angle of them to begin with plus the added angle of the bike. i know 2 weeks isnt as long as some people may think but it is long for me i ride it at least three times a week. i also relocated all of the electrical components that are located inside the tail section to underneath the front seat. im not sure if that may cause a problem or not. i do know that the air box is clean no mice nests or anything and no rust in the tank. thanks for input, hopefully i can put some time in on her this weekend and get something figured out.

[kilika2]

I know this is way simple and don't take it the wrong way. Is the petcock on reserve? Some bikes will put a rev limiter so you can make it to the next station. Usually 4k not 3. But it's something else to eliminate.

Chris.

[jmcmotorsports]

i think i switched it between on and reserve to see if that would do anything. but it was the same either way. i dont believe the fzr has any electronics to the petcock but thanks and any input is appreciated, no matter how small it may be.

[yamaha_george]

i think i switched it between on and reserve to see if that would do anything. but it was the same either way. i dont believe the fzr has any electronics to the petcock but thanks and any input is appreciated, no matter how small it may be.

hi,
having never left ethenol standing personally this may seem odd but does it go "stale" quicker than gas, I am wondering if the high speed jets are gummed or having stood the battery is low and not allowing the engine to rev out. FZR's are a pig for that.

[jmcmotorsports]

the ethanol fuel, for lack of a better word at the moment, does go stale quicker than non-ethanol. for a bunch of different reasons, those im not 100% sure about. i havent checked the battery but that does make sense. i dont believe its a carburetion issue though, only because it runs perfectly as it did before until i reach the higher rpm or throttle opening. i will check that and take it for a test ride tomorrow , maybe give the battery a charge and see if that helps.

[yamaha_george]

the ethanol fuel, for lack of a better word at the moment, does go stale quicker than non-ethanol. for a bunch of different reasons, those im not 100% sure about. i havent checked the battery but that does make sense. i dont believe its a carburetion issue though, only because it runs perfectly as it did before until i reach the higher rpm or throttle opening. i will check that and take it for a test ride tomorrow , maybe give the battery a charge and see if that helps.

J,
ok get back to us after the battery has been fully charged overnight & you have had a ride.

[thatkid]

i also relocated all of the electrical components that are located inside the tail section to underneath the front seat. im not sure if that may cause a problem or not.

You relocated the VR, Main relay, Main fuse, and Flasher relay. Which type of VR do you have, the old small type or, the newer finned type? if its the old one, did you ground the VR's alloy body? The VR leaks excessive voltage to ground, the old VR leaks it VIA it's alloy body, the newer VR utilises its ground wire.

IF not that VR will be kicking out far to much DC voltage @ 3000 rpm. You could have the newer type Ignition Transistors in your TCI which I believe shut down if too much voltage is delivered to them. I can't find the post by DonTZ125 (Thank You) but i think that is what they do.

The Main relay performs several task's. Some of which are, it manages the safety switches, supplies power to the TCI, and houses the fuel pump relay. All prongs in the VR and Main relay should be squeaky clean, not a simple task by hand. I use Servisol Switch Cleaner (duno if it's available that side of the pond) on the prongs and the connectors. Beware that stuff is Inflammable so allow it plenty of time to evaporate!! especially on the VR which has AC inputs ranging from 40 to 60 volts.

Good luck
Mal

[jmcmotorsports]

I have the newer style vr which is the finned type and grounded by a wire. I moved the ground wire to be between the right side tail piece and its mounting bracket that is under the front seat. If it does not have a sufficient enough ground, could that make a problem like this?

[DonTZ125]

There could be paint, corrosion, squirrel vomit fouling the grounding bolt. You might try adding a splice to run the VR ground back to the battery -ve terminal.

[thatkid]

IF it doesn't have a sufficient ground kiss goodbye to your electrical component's, TCI, Flasher relay, Tacho, bulbs E.T.C. plus your battery will get boiled removing paint in the surrounding location, the battery breather tube will leak acid removing the paint from your swing arm, that battery will also need replacing.

Check your charging voltage ASAP. Charging voltage should be 13.7 to 14.9 volts anything higher will systematicly KILL your electrics.

I'm unsure whether or not you VR will have sufficient air flow to cool located under the seat, if not it will overheat. The VR connections will degrade/oxides causing an increase in resistance therefore an increase in temperature = fried VR.

I fried 4 old VR's I have a R6 tail and figured it was lack of airflow/cooling. heres where I mounted mine.

[sweekster]

i could be wrong here (has happened before), but seeing as there isn't any mention of the bike stalling and then going dead doesn't lead me to believe this is a VR issue. There's no mention of any weird electrical gremlins either. Just that there is no mid range and top end power. This sounds more like a fuel (or lack there of) issue. JMC have you actually looked at the carbs? I ask because this sounds more like you have a clogged main jet or two as opposed to a bad VR. I would check that out if it were me.

[thatkid]

i could be wrong here (has happened before), but seeing as there isn't any mention of the bike stalling and then going dead doesn't lead me to believe this is a VR issue. There's no mention of any weird electrical gremlins either. Just that there is no mid range and top end power. This sounds more like a fuel (or lack there of) issue. JMC have you actually looked at the carbs? I ask because this sounds more like you have a clogged main jet or two as opposed to a bad VR. I would check that out if it were me.

I thought fuel starvation maybe I didn't explain that properly, no offence intended.

If you mean the bike revs to say 3k and stays there with no misfire, probably carburation. Running rich usually causes low RPM issues.

We are all guessing really, so most of us will be wrong

This is my experience from 4 fried VR's in 12 months, the VR on one occasion was kicking out 19 volts DC.

Blown Headlamp & Dash bulbs (not always immediately) 2 boiled batteries and loss of paint on the swinger, 1 fried turn signal relay. NO fried TCI No fried Tach. Three times when my battery was dead, I got the bike jump started and rode home with no running issues whatsoever.

Flat batteries have never caused my bike to run poorly, nor overcharging VR's. The other issues I have learnt from other members experiences, and thought the OP should be-aware of the dangers.

Thankfully after I found my way here, then discovered the VR upgrade mod, that is what im running now

[jmcmotorsports]

i havent had a chance to look at the carbs yet. before i moved the electrical components it ran fine. all of the other electrical things, like flashers still work. i do not have a factory dash though, so that may show me something else. the bike runs to a certain rpm around 3-4k and then sounds like a rev-limiter or anyone that has ever heard a drag bike run it sounds like a 2-step. it stays at that rpm and doesnt get higher. i didnt clean the paint where i moved ground for the vr but i am going to do that and possibly move it to a better location where it will stay cooler. thanks for everyones help! it is very much appreciated.

also, what is the vr upgrade mod, if i find out that this is the problem then i will end up going that route.