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Discussion Starter #1
OK, so my bike is a 2002 with 26K miles on the clock. The bike has never given me a problem in the past. PAIR and Flapper still in-tact, Jardine Slip-Ons and K&N filters.

Recently the bike has seen less use from starting a new job and just not having much time to ride it, but all was well until one day it just had a hard time starting and then wouldn't idle right when trying to leave the gas station. The idle got lower and lower and would eventually die.

Here is the odd part - the bike, when cold, seems to fire up just fine and idle nice for a minute or 2. As it gets warmer from riding, the idle get worse and worse. Sitting at a light, the idle is bad enough that it will stall if I do not blip it on occasion. I have turned the idle up to about 1600rpm when cold and it will try and slow down but wont die... but when its cold, its too high and warm its barely hanging on.

I have checked air filters and fuel - fresh fuel and pump is working and within spec. I have not done spark plugs yet or dug any deeper into it.

The strange thing is that it feels fine under load and pulls hard and sounds good.

I did notice a slight rattling noise from the engine that I cant quite pinpoint yet that wasn't there before. seems to be coming from the bottom end but I havent had the fairings off to know for sure but it has me concerned.

I do ride the bike fairly hard for a street bike. I do not abuse it though. It has never been on the track to my knowledge. I have hit the rev limiter with it 2 times in my ownership - once from a late shift (not paying as much attention as I should have been, and once from a missed 1-2 shift. both were early in my ownership.

I plan on doing the valves soon as I don't know when or if they were last done.

Thoughts on what this could be? I am pulling my hair out trying to sort this because there is a bit of inconsistency to it.

- Justin
 

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Discussion Starter #3 (Edited)
FPR do a search
I have already read up on that... but seems to me if that was failing, I would also have problems throughout the rev range, wouldn't I? and not sure how engine temp would affect that as well. I will certainly look into it though. Is there a procedure to test or check the regulator?

- Justin
 

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Discussion Starter #4
ok, so after some more skimming, it sounds like that is exactly my problem. yay. I will get one on order and go from there.

- Justin
 

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Do the plugs too. They are cheap fix in many cases and being iridium tipped are very easy to foul. I've seen just one bad start kill many sets of RC51 plugs over the years. A taste of water in the fuel or an accidental blip of the throttle while starting can lead to a burp of too much fuel hitting the plugs and they never work the same after that.
 

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Check the FPR by switching the key on to prime the pump and pressurize the fuel line, then switch off.
Pull the vacuum hose off the diaphragm side of the FPR.
If fuel drips out the fitting, it's done for. Replacement time.
 

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wow LDH - I never heard of just blipping the throttle damaging plugs. I am new to the RC - Always raced I4's.. So should i stop blipping the throttle when i start it? replacing my battery once it arrives because shes hard to start, even more so since I put the PCII on it.
 

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Discussion Starter #8
Do the plugs too. They are cheap fix in many cases and being iridium tipped are very easy to foul. I've seen just one bad start kill many sets of RC51 plugs over the years. A taste of water in the fuel or an accidental blip of the throttle while starting can lead to a burp of too much fuel hitting the plugs and they never work the same after that.
that has me curious as well because when its hot, i have to almost hold my throttle about 1/4 open to get it to fire now... maybe its both. The FPR is cheap enough that I will go ahead and do that anyway, and the plugs and valve job were on my list already so I'll likely knock that out next week assuming I dont get sent to Phoenix for work on Monday.

After this thread and reading up some more on the fpr, I am about 95% confident that is the problem, coupled with the potentially bad spark plugs. Easy enough.

none of this explains the slight rattle I hear at idle still but I can tackle that one when I have it apart.

keep the ideas flowing though if you have any more just in case.

I will update more as I get into it it. actually its no likely that I will be able to get the FPR here in time anyway, but imma try.

- Justin
 

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Fuel injected engines never need to be pumped or blipped during the startup. In fact the RC51 never needs to be blipped period except when rev-matching on downshifts and I don't even do that as it messes up the precision of my trailbraking technique.

Also always check to make sure your Throttle Position has been calibrated within your Powercommander software.
 

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Discussion Starter #10
Fuel injected engines never need to be pumped or blipped during the startup. In fact the RC51 never needs to be blipped period except when rev-matching on downshifts and I don't even do that as it messes up the precision of my trailbraking technique.

Also always check to make sure your Throttle Position has been calibrated within your Powercommander software.
I has no power commander. never really saw a need for it.

- Justin
 

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Discussion Starter #12
maybe I'll pick one up then. I have a buddy that is trying to sell me a PCIIIUSB for a bill. either way, i'll get the FPR sorted, new plugs and valve adjustment done, then go from there.

- Justin
 

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Everything you described is what my bike did too. FPR.
As already stated, lift the tank, pull the small vac hose off the fpr, turn on the key and look for leaking from the fpr nipple as the pump primes.

And damn son! get a PowerCommander on there. You'll feel the difference immediately with the correct fuel map.

 

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Discussion Starter #15
OK, just wanted to drop in with a quick update... FPR was the culprit! Took the vacuum line off and it was a steady stream of relatively high pressure fuel.

Replaced the FPR and this thing is a whole new bike! The bike starts and idles smoother than it ever has before which leads me to think that this has been a problem since before I got the bike that has recently become way worse.

Anyway, Thanks to everyone who mentioned and confirmed the FPR! I would have chased that around for weeks trying to find the problem and likely never would have.

- Justin
 

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I've been telling That Guy about getting a PC3 for years.

Now that it's fixed let's go ride!!


Sent from Motorcycle.com Free App
Take him on over to DynoJet and let some of their experts work him over too...if LDH offers up some advice, rest assured its pretty spot on and will work.:cool:
 
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