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taksi

Joined:

Oct 11

Posts: 9

taksi says:

loss of power

I have a '58 plate FZ1 Fazer that has developed a peculiar and severe loss of power at low revs. If I'm idling up to a traffic light or junction at idle to 2000 revs and open up there is a severe loss of power till it reaches 2500 revs then  she's off like a rocket. If I slowly open the throttle there is no problem. The bike has a full Akrapovic system so no cat or ex-up. There are no fault codes showing on the dash though it does seem like an air problem to me.

I've checked all the connectors under the seat and the tank including ECU and TPS and have changed the plugs and checked the air vacuum hoses for the Scottoiler take off, also changed the fuel to Shell Vpower, nothing seems to work. I have spoken to two Yam dealers and they say I've done everything they could think of as well!  Any help would be greatly appreciated. Ta, Taksi.

 

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  • Posted 3 years ago (28 January 2012 11:46)

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robsot

Joined:

Feb 10

Posts: 871

robsot says:

..

i havn't got many ideas really ( sure others on here will have) could there be water in your tank maybe?? try putting 100ml of meths in to a tank of fuel and seeing if the problem goes... 

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oscarthegrouch

Joined:

Oct 05

Posts: 3108

sounds

like an air leak to me between airbox and inlet manifold

did the bike run fine before fitting the full acka exhaust ?

Has it been re mapped ??? i have heard people saying fitting fuel cut out eliminators heal the jerky throttle problems on and off the throttle due to the injection system not fuelling on a closed throttle but your problem sounds different  ..... one for kcmc this?

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kcmc

Joined:

Jan 08

Posts: 7160

kcmc says:

Yamaha FZ1 Fazer 2008 ?

Hi Taksi

You don't say when the problem started?where you just riding along and it started doing it?.To me it sounds like a flat spot,probably caused by fitting a full Akrapovic system?so now the bike is running to lean,so when you open the throttle it gets too much air before the electronics can catch up.If you have a full system,then both the EX-UP motor and the oxygen sensor will need a device to to fool the ECU,are both of these in good repair?.Also do you have a free flow type sports air filter fitted,if so you will need a power commander  to sort the fueling out.If everything was OK and the bike just started doing this then it could be an fueling or electric problem( air temp-sensor or something?)but would probably go down the fuel contamination route first,and try putting 100-150ml of methylated spirit in with a full tank of petrol and run this through the system to see if this makes a improvement.(Metho mixes with both water and petrol so will clear any unwanted water out in the fuel system) its probably just running to weak though?Good Luck

KCMC:tongue:

P.S. Oh while am thinkin on it,whats the idle speed?could be worth lifting the idle to 1200rpm if not already,its both good for the pick up off the throttle and on the over run gearing down:smile  

[This Reply has been modified by the Author]

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taksi

Joined:

Oct 11

Posts: 9

taksi says:

loss of power

Thanks for the replies. The Akro has been on since new and I have commuted daily for the last 18 months. Idle speed is 1200-1300 rpm. Rode it no problem for ages then washed it on a Saturday after work and it ended up being left in the garage for a couple of weeks due to icy roads. When I used it again the probs started and thats why I thought of condensation in electrical connectors/fuel tank. Never had these probs last winter though. Taksi

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oscarthegrouch

Joined:

Oct 05

Posts: 3108

well you just answered

your own question there  bad connection possibly or contaminated fuel:biggrin:

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kcmc

Joined:

Jan 08

Posts: 7160

kcmc says:

You

can try the metho,or if you think that's a bit weird,you can try  Wynn's dry fuel (sort of does the same job).

http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_193117_langId_-1_categoryId_255221

Good Luck

KCMC:tongue:

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taksi

Joined:

Oct 11

Posts: 9

taksi says:

loss of power

I'll try the metho I think. The bike's been washed every week for 18 months and left in the garage overnight/weekend with no previous problems. The bike rides normal if I open the throtttle smoothly/slowly but if I snap the throttle open a bit quicker it doesn't want to know and is fantastic over 2500 rpm really smooth with no hint of a misfire,  which sort of leads me away from electrical conections. It's not a misfire but loss of power. It's a severe "chugging" sort of thing, really weird to describe. If you imagine driving a car at 20mph in 5th gear and try to accelerate you get a similar result. I'll have another look today but I'm grasping at straws now. I'm afraid that if I take it to a dealer I'll have to empty my wallet if they spend as many hours on it as I have. I still think it's intake related though. Hey ho.

[This Reply has been modified by the Author]

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smidget

Joined:

Nov 07

Posts: 2406

smidget says:

Hi taksi

Could you post a list of all you have done to the bike since you washed it and then stuck it away for the week-end that way you will eliminate some of the checkes that could / would be suggested.

Will answer after you.

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kcmc

Joined:

Jan 08

Posts: 7160

kcmc says:

Yamaha FZ1 Fazer 2008 ?

Hi again Taksi

As you say it could be an expensive exercise to find the problem if as you say its not showing any fault codes,which seems odd if its such a problem fault?.As i have said before the EX-UP motor and oxygen sensor will have had to have ECU,fooling devices fitted to compensate for the full system.So could be worth checking these out,and the fault codes again?you also say that you have checked all the pipe work at the throttle body's,check them again,there's quite a few under there,especially the double joint with the top one going to the pressure sensor on the common rail.Are able,or capable of doing a throttle body balance?as this also could be another thing that has go out?(but would have to be a long way out as the ECU's these days can compensate for quite large margins not like the old carb bikes).Also you said you checked your throttle position sensor?how did you do this?and i think your bike has two anyway.Good Luck

KCMC:tongue:  

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kcmc

Joined:

Jan 08

Posts: 7160

kcmc says:

And

also what Smidget said:smile''would help''

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