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Discussion Starter #1
Yes, I'm aware of the SEARCH feature, but I'm trying to see if there's anything I'm missing. :D

So! Just joined here a week or so ago, and I mentioned there's some minor technical issues with the new ride.

Anyway, I got her stripped down today, and I'm determined to figure out what's going on.

Bike had a hard time starting, but changed the plugs first to some brand new iridiums. Sure enough, it fired right up (with a little choke). After pushing the choke back in, the bike promptly died again. Holding the throttle open, it runs and sounds smooth. My concern is how the plugs that a removed looked (attached a photo).

So I def had a problem running rich. Powercommander 3 was NOT hooked up, and I could smell fuel out of the pipes. Plugging in the PC3 actually helped with the 'rich smell', and the guy who sold it to me said that there's actually a custom map saved. Great!

However, when I let go of the throttle, the bike dies, WITH or WITHOUT the PC3. With all the mods on this beast, it def needs the PC. But where do I go from here?

Status:

*Dies on throttle release

New Plugs
Fresh Gas
Checked spark, nice and blue
Smooth rev range (w PC3)
Gas smell (without PC3)
**Tested Fuel Pressure Reg (vacuum check, no leaks, not dripping fuel)
No FI codes.
All sensors accounted for, although the front MAP sensor doesnt have a hose attached to anything (normal w mod supposedly? gonna follow up on this next)

Air/ fuel Mods:

Carbon airbox (see photo in intro thread
Ram air
Velocity stacks
PC3 custom map
Ladybird dual + midpipe
PAIR / flapper
HRC 1/6th turn (maybe loose causing low throttle death? Seems hooked up tight and fine to me)

One of my buddies mentioned idle adjust. It wouldn't be that simple would it? Isnt that more of a 'bandaid'? Any ideas?
 

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Wow, look at the carbon soot on that plug! Good to hear you already checked the FPR.

I'd start checking for vacuum leaks if it's dying at idle; make sure there's no air "leaks" so to speak because the bike is having a hard time staying running at idle without throttle input.

Will the bike idle OK with a zero map while the PC3 is hooked up?

Once you sort out the idle issue, you'll want to examine what the values of the "custom" map were like in your PC3 and possibly consider getting a proper dyno tune.

G'luck!
 

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The choke or fast idle is needed to warm the bike up when cold otherwise it may stall.

Before anything I'd measure and adjust idle to factory spec as noted in the service manual when the bike is warm and choke/fast idle is off. Only then if it dies when the bike is warmed up would I say there may be a problem with something else.

Did the PC come with the bike? If not, then the custom map is not for the bike.
 

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Discussion Starter #5
I'll search for vacuum lines, but they seem to be fine as for the few I've noticed as I've poked around. I'll dig harder though.
And yes the PC3 came with the bike, the guy I bought it from is actually a friend and co worker of mine, he misses it ;) Anyway, he had it tuned at one point. The map in there is saved from that time.
The bike sat in the garage for a few months, was giving him trouble, and that's when he disconnected the PC. Ran it like that for a while, hence the black plugs I'm assuming. Like I said, bike definitely seems to rev very well w it installed. I'm just stumped withy the whole dying at idle thing. Like, I can hold the bike very lightly with the throttle at 1300 to 1500. Let go? Dead. Very strange.

I think I may try to get it out on the road and run a few miles and check my plugs again.

Loving the input guys. Anything else?
 

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Also check this. When the pair mod is done it will expose a vacuum nipple on the front throttle body if the hose is removed with the vacuum canister. Double check that either the hose is still there and plugged, or that there is a cap on the nipple if the hose was removed. Probably not the problem, but would represent a vacuum leak if not done correctly.
 

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Discussion Starter #8
Once you confirm idle is not low, I'd guess fpr. Google fpr idle rc51 for some threads with info.
Yeah I've seen some of those posts. But I pulled the vac hose off it and checked for leaks, or dripping fuel, and the hose looked clean. FPRs brand new are cheap thankfully. Do you think it's worth it to just strap a new one on anyway? Just to eliminate that as a possible issue?
 

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Yeah I've seen some of those posts. But I pulled the vac hose off it and checked for leaks, or dripping fuel, and the hose looked clean. FPRs brand new are cheap thankfully. Do you think it's worth it to just strap a new one on anyway? Just to eliminate that as a possible issue?
Sounds like the fpr is okay. Again, before any testing of parts I'd check/adjust idle to factory specs. Many people set it too low, and someone could have monkeyed with the adjuster.

If you don't mind collecting parts and spending the $$ it doesn't hurt to get another one, but it doesn' sound like it is the issue and I'd troubleshoot the rest of the possibilities before circling back the the fpr.
 

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Discussion Starter #12
Thanks guys. Well at least I have a few things to try. I'll report back when I figure it out, got a few work days ahead of me (good ol' responsibility and such... Ugh) so I'll update then. Ride on!
 

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Discussion Starter #13
Update: So as some of you may have seen in my intro thread, I was in search of a non bent subframe. I found one, for a ridiculously cheap price, and it's straight as an arrow (pic attached)! I haven had a good chance to work on the bike, so problems still remain. That's half the reason I bought this though, it's my dream bike, and my project for now.

Interesting theroy that a friend of mine brought up, but he listened to the bike run, and he insists I'm running on one cylinder. I'm pretty sure I'm not, but I didn't have time right then to check, dashing off to work. But let's say for arguments sake, if I am down a cylinder, what do I check? No smoke or crap and the oil that I have seen... Thoughts? Anyone have their RC not fire both cannons?
 

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Discussion Starter #14
Well guys looks like I need a good tune and maybe a fresh coil and we're good to go. Thanks for all the quick replys. Gonna start a new thread for pics of my work in progress, and all the damn mods on this thing.... Anyway, got the new subframe in. See ya around here!
 
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