Hi guys, I have a desperate loss of power at very low revs and wondered if anyone could throw any light on it. Bike is a '58 plate FZ1 fazer with full Akropovic, minus cat and ex-up and no power commander. Came like that from the showroom 2 yrs and 12k ago. Symptoms are these. Approaching traffic lights/junction on a closed throttle up to 2000rpm in 1st/2nd gear 20mph'ish and open the throttle. There is then a severe loss of power like it starts,stops,starts,stops etc very rapidly until it reaches 2500rpm and then she's off like a good 'un. So far this is what I've done. I'm a car mechanic by the way, though this deep into a bike fault I'm getting a bit lost.
1. Checked oil/coolant levels. If the oil is low on a modern car engine it will lurch into "limp mode". No probs all ok.
2. Changed the plugs (which have only done 2k) for the old ones for elimination purposes, still same.
3. Let the tank empty and refilled with Shell Vpower and checked idle speed was 1200-1300 rpm. Still same.
4. Removed the tank and checked all the electrical connectors I could see, snapped them open, all nice and dry and refitted. TPS, O2 sensor,primary pump,injectors,plug coils and ecu. Still same.
5. Checked vacuum hoses were connected to the throttle bodies correctly, including Scottoiler pick up. Checked rubber seals between upper and lower airbox halves and airbox to throttle body gaskets. All ok. Road test again, still same.
6. No fault codes shown on dash. Removed air sensor conector from top of airbox and turned ign on. Code 22 appears on the dash indicating that the fault code reporting to the dash is ok.
At this point I feel 10 yrs older at the thought of going to my dealer and totting up £57 for each hour they look at it aws I've already spent 20-25 hrs in my garage.
I've just managed to get a PDF of the official workshop manual off flea bay for a couple of quid and it's pretty damned good. Only thing now is, via my new manual, to check the ohm values on the throttle position sensor and hope for the best.
Anybody out there got any previous with a similar fault or just any ideas as my head hurts now.
Ta in advance,
Taksi
