Yes it was low. multiple possible reasons why this could be. I believe it was because of the location in line. Talked to mech and engineer. Common enough and said I was fine.

 

okay. i have checked and re-checked the functionality of the air solenoid valve (using the test given to me by the manual) and performed the same test to the working F4 in the garage. It turns out that the valve is working fine. there is a substantial resistence the input gives but is varied (that is, the more air pressure, the more open the valve gets... it just seemed like too much resistence to me when i ran the tests... the other bike is the same though). WHERE IS THAT DYNOMITE? I think its time for my bike to have an accident.

i am thinking that the floats are faulty in some way... when it went down, it is possible that one (or more) were frozen in the up/open position and are letting in too much gas in but am not too sure. or maybe closed, i dunno. it seems to have symptoms ofbeingflooded with too much gas when it dies.i cant think of a way to test them.

it looks like i am going to have to pull off the carb assembly and rebuild the floats to be sure.

what do you think?

 

i am going to start with electrical first. i will be trial replacing the ECM and the relay and then do the carb floats if that doesnt work. i will post my results.

 

Jack:

As I understand, a carb needs a pressure differential to work. There needs to be a lower pressure inside the carb than there is outside, for fuel to be drawn out of the float bowl through the jets and on down into the combustion chamber. That's the way my old Mikuni's worked anyways.

So maybe what was happening was the ram air function was overcoming the vacuum inside the carb and therefore no fuel was being drawn.I would really liketo know exactly what is going on in any case, because I am soon going to have to deal with issues around ram air.I don't have the solenoid, and I won't have ascoopout in the air stream since I am putting one of these motors into a small formula car.

Now a question:

Why in heaven's name would there be an overlapping arrangement in this venting system. IOW why have both a low and high speed venting systemwhen it is apparently OK to have the high speed system open always as it is when the solenoid fails? Any ideas?

 

Jet mechanic... come on over and fix my piece of **** 900rr. lol. The thing doesn't make the kind of power it should be making imo. I can barely throttle up a power wheelie and that should be cake.

I'm replacing the stator once the new/used on arrives. I think I know what my bike's problem is though.. slightly leaking seals on the enrichment valves(choke), causing the plugs to slightly foul. Also i need to check/adjust the valve shims, and then dial in the manual cam chain tensioner to spec. My bike feels like it's putting out 90 hp not 120hp like it should be at the engine. I wish i knew someone who owned a dynomometer and was a great tuning mechanic.

I've tested EVERYTHING electrical on my bike, the wiring, all the electrical components according the tech manual for my bike. This is part of the reason i'm replacing the stator, it tested bad, that and it kept frying my new batteries i'd buy for it. Wasn't a voltage regulator/rectifier problem either, that tested good.

I have noticed the 900rr runs better with a paper air filter, than a gauze type filter.

I also have a stageII jet kit with 120 main jets ( bike freaking flies above 8K rpm) and a BMC race air filter. I need to put the stock jets back in the carbs and then synch the carbs to spec, remove those and then put the stage II kit back in it. Impossible almost to adjust the carbs with a jet kit installed in them. The mercury gauge won't stay steady.

if there is a good mechanic with dynomometer and tuning experience..i'll trade work for your services. I make carbon fiber parts professionally. I'm in Phoenix AZ.

 

Update:
Still not working!
that being said, i have since:
1. Replaced the Ingnition Pulse Sensor and Spark wheelback to stock (had an advancer in it)
2. moved the air hoses to the AIR Solenoind Valve and zip tied them next to the ram air tubes in front
3. been to a honda mechanic that moved my air solenoid intake valves a bit more to get more direct air in the valve. (he also checked the tank valve even though he just verified that it works.. i tested that too). It hit 80 and seemed better at first. I didnt have time to really test it out over a mileuntill yesterday... no dice. It still seems gutless and dies coasting at 60-70 mph. It just starts to loose power and throttle response and then dies (thud) once the clutch is pulled in. He took it for a short spin and didn't notice anything, he didnt have time to really test it out but i told him i would let him know. (they are on a week+ break so i cant get it to him til then).

It feels like it is flooding out when it dies to me. It wont refire until it sits for about 5 minsand then it runs very rough (only at low speeds) until it sits longer.
I feel i have done everything in my knowledge base to fix this thing and am on my second mechanic (i havent given up on him yet, but he needs more time with it).

Please review everything in thisabove(or ask)for what has been done already... it's a lot!

I noticed when i replaced the ignition pulse sensor that the connection fitting on the outside of the case (plugs into the wire harness assembly) was charred and i had melted plastic around it. i thought it was the result of the wire resting on the hot transfer case and motor so i moved it out of the way with some wire.
i am thinking that my stator might have taken a crap on me but am unsure. the cover was damaged when it went down but not too bad... no holes or anything. is it possible that the impact caused a failure? Unless its simple sodering, Electrical is not my forte. I am also thinking a compression test or full carb rebuild might be in order.
I am still baffeled.
thanks for all your help!!!!

 

SORRY IT TOOK SO LONG TO UPDATE THIS... I HAVE BEEN BUSY AND OUT OF TOWN A LOT>

ITS DONE!!!!
finally up and going! thanks for the help:

it WAS the Air intake form the Air Solenoid that was not getting enough airflow an flooding out the carb barrels. if you have this problem, be sure that the two tubes in front of the bike (the upper cowl just next to the ram air (that goes into the airbox)) are in the highest airflow possible. my aftermarket fairings didnt have aspot for them so i needed tozip tie them inplace.

mine was not, and it caused mixture problems that flooded the bike out at higher rpm ranges. THANKS AGAIN TO ALL

 

Frankmackie,

Sorry we never go in touch on the phone. Glad to hear your bike was is up and running. It's btich to find out that it will take two zip ties to get you back on the road, eh? I wasn't getting emails letting me know you posted again. Just checked it now. Sorry mate. I hoped I helped out with my info. To the other riders out there with this problem, Let me know if you have this problem. Email me, call me, smoke signals, what ever it takes to help out with this frustrating problem.

Ender
Rival Riderz
Oceanside, CA

 

i was having the same problem, i brought it to a mech and he cut out the hoses and gravity feed my bike prob went away, should i be affraid?

 

If the problem went away I'm sure your fine. It wil happen as soon as you pick up speed so I'm really sure you're fine. Have you opened her up since the modification? That will be the real test. Can you give more info on the gravity feed?

Ender
Rival Riderz
North County San Diego