[TDaddy]

i'll shoot this question which has been bothering me for a year over to you folks... i've seen two dealers, talked to dealers in new hampshire, california, and arizona to no avail. It's not a serious problem in that it causes danger to me or my bike, but is a huge inconvenience whenever it occurs.

My 2001 fuel injected 900 beast tends to dislike hot and humid weather. I'm talking about 90 degree 80% humidity days. after riding on fast roads for 30 minutes then stopping for a drink or to gas up my bike, it will start up just fine but about 40 seconds later my bike won't want to rev past 4000, doesn't matter if i'm moving or stopped; exhibiting these symptoms:

1. she'll have no power,
2. she'll idle really rough and if i don't give her 5% throttle to keep the rpm's above 1500 she'll quit
3. to start from a stop i have to rev above 3000 and slip the clutch or else she'll stall
4. once i'm going if i try to hold it at a steady rpm the exhaust will pop like a damn minigun which gets loud as hell when i decelerate.
5. if i give it throttle, it sounds like it's sucking air normally
6. it feels like there isn't any gas being fed to the engine

Here are several suggestions i have received (all have failed to solve the problem):
1. swap out the ECU
2. get rid of the charcoal canister
3. install new pipes
4. open up the airbox
5. take it to your dealer
6. use different gas
7. remap your ecu
8. check your spark plugs
9. check your oil level
10. check your valves
(notice that most of the stuff on this list is what prompted me to hack the crap out of my bike and throw on a bunch of aftermarket stuff)

Here is what works:
NOT RIDING WHEN IT'S HOT OUT...

...which is like abstinence, yeah it works but it ain't no fun! although it's a huge inconvenience i can't really mind it because i'm more inclined to wear my gear since i only ride when it's cool out. riding with a leather jacket when it's 90 out sucks!! I think i covered everything. a suzuki mechanic mentioned that maybe the relays in my bike are sticking. this is the most promising lead i have thus far mainly by process of elimination! as i'm typing this i'm wondering, is it possible that the fuel injection nozzles are sticking due to the heat/humidity combo?

the only thing that works is i have to let the bike totally cool down ~2 hours before it will ride normally. which is out of the question if i'm 10 down the highway from my house

I don't want to take my bike to the dealer and i don't want another bike. i like the one i have so i need to lick this problem, know what i'm sayin?

**before any potential ducatisti question the reliability of these machines, let it be known that i have never heard of anything like this on ANY bike or car. it's just a fluke problem with my particular bike**

 

[ciscoguy]

Are all your vent tubes open? The lines aren't pinched or anything. Did you try opening the gas cap when it happens, and did you hear air, or does the problem still exist?

Maybe the ECU overheats, and screws up the mapping. I would take it to a dealer and make them FIX it. You have a two year warranty.

 

[TDaddy]

where are the vent tubes? i've been making sure that my gas line isn't pinched and when i open the gas tank it doesn't sound like there is a vacuum. the idea about the ecu overheating is good except my dealer swapped it out once and my bike was still jacked up. maybe at the end of this riding season i'll have to take it in, but then the problem will be harder to replicate since it'll be cooler out. i don't know, at this point i'm ready to throw the towel in and let this rest...

 

[Gman86]

How about Vapor lock?

 

[test-reg]

vapor lock is highly unlikely, but possible on a fuel injected bike. unfotunately, the bike needs to be diagnosed while the problem is happening, otherwise, it's guess work. if it was a car, i would suggest driving it with test equipement on it, but, obviuosly, not practical with a bike. your best bet may be to get it to a shop with a dyno. my guess is you are looking at an intermittant elecrical failure.

 

[Ken_the_Carp]

Re: hot weather issue incl. history  (LONG story)

My first thought was that you had a bum spark plug, but it would still be a "bum plug" when the bike cooled down, you might have a defective coill ( ignition or pickup )

 

[TDaddy]

hmm, vapor lock? maybe this will rule that out: last time this happened i was low on gas so i filled the tank with 2.3 gallons of COLD gas. i let her sit for 15 minutes and when i started up she went back to being a little bitch.

??? ??? ??? ???

 

[Gman86]

Is your fuel line routed near a hot spot on the engine? If it is vapor lock, your gas may be heated on the way to the engine. I am not sure, just throwing out thoughts.

 

[TDaddy]

yeah, that's a good point, one thing i learned was that the gas line tends to get pinched when lifting and lowering the gas tank. i have been very careful lately to make sure that line isn't pinched. hmm, maybe if it happens again, when i get gas i'll try agitating that line to see if that'll help. either that or i'll carry around a small bottle of freon to cool the friggin thing

 

[Gman86]

Hey TDaddy! Here is another link that is related to the overheating thing.
http://mototuneusa.com/ten_free_horsepower.htm

 

[Speeddog]

Re: hot weather issue incl. history  (LONG story)

My SWAG is a bad injector or a bad ignition coil.

If it was a relay problem, I think it wouldn't run at all.

Next time it happens, you can do the "lick the finger and check the exhaust pipe" to see which cylinder isn't firing, at least that cuts your list of suspects in half.

Try pulling the plug wire on the bad cylinder ( engine off ), and put a spark plug in it. Ground the plug against the engine and try and start the motor. See what kind of spark you get, if any. Do the same thing when it's cold to get an idea of what the spark looks like then.

 

[TDaddy]

hmm, i'll try that out, maybe a cylinder isn't firing...

thanks for the heads up GMan! alright so here's what i'm going to try next time it happens:

1. check to see if a cylinder isn't firing
2. pulling the ECU and cooling the friggin thing down

thanks fellas, i'm headed in the right direction!

 

[Gman86]

Hey TDaddy! Keep us posted if our suggestions work or not. That's good information to know and to pass around.

 

[test-reg]

could someone please explain what idiom "pregnant dog" replaces? prhaps the origional word(s) with some *** would work.

 

[test-reg]

thanx!

 

[TDaddy]

FIXED!!! ABOUT FRIGGIN TIME, AND NO HELP FROM ANY DEALERS!!!!

long story short, i was cruising the BB and came across the thread "Won't power-up or start - please help" and saw Speeddog830's pic of the ignition and fuel pump relays. So i went for a quick ride, came back, let the bike sit for 30 minutes and then went for another ride. Sure enough, about 3 minutes in the bike started ca-chugging it's sorry butt down the road. I pulled over, SWITCHED the two relays, started it back up and the problem was gone!!

To verify this, I got home, stuck the bad relay in the oven and while it was still hot i stuck it on the bike. the bike ran crappy. i took the relay off, cooled it down, and put it back on. bike ran fine!

So now i gots to get myself a new relay from the store, my bike is due for an oil change, and i just picked up a "how to" vid on checking the valves from ProItalia. This is gonna be a fun fall!

ROCK

 

[Speeddog]

Re: hot weather issue incl. history  (LONG st

Glad I could sorta help........

Just for the memory banks, which relay was bad?
Was it running poorly with the bad relay in the "injection" position or in the "ignition" position?

 

[TDaddy]

hola! it was the fuel pump relay that i switched out. BUT it looks like i may have spoken too soon because I went out again with the two relays switched, the bike started acting up again. oh well... the good thing is this only happens when it's crazy hot outside. now that fall is falling upon us i won't have to worry about this until next season... back to the drawing board

 

[erex]

TDaddy,

I had a similar problem happen to me a few times. My problem usually happened after I fueled up on hot days. I was able to solve the problem by simply filling the tank less. Intead of 2.3, just right at 1.9 or so.
I haven't had that problem since I started doing this 9 months now.

Good luck,
-e

 

[TDaddy]

so yesterday i rolled with the group of monster riders i met here on the internet and we went to superbike italia in lemont, IL. ken, the main dude out there, gave me the best explanation yet of what was going on. unfortunately there is only a dim light at the end of the tunnel for this issue. here was his explanation:

"your bike is air cooled. after riding and letting it sit all that hot air is going straight up into the cylinder and the bike is simply cooking. no oil is circulating through the engine, and no air is dissipating any heat. when you start the bike back up, your ECU is reading an overheating state, causing it to back off on the fuel delivery until temps go back down. so when you jump back on the bike and get the air going through the engine, you'll be cooling it back down and after a little while, your bike will run normally.

"the only thing i can suggest is putting some full synthetic oil such as AGIP in your engine. get rid of that regular crap. by putting in synthetic that should help your problem."

so there it is. the only straight up explanation i've ever had from any ducati tech. sounds logical, don't it?