No power under 3000 rpm

[asphaltsurfer]

Hi guys , i'm new in this forum

i just bought a '92 fzr 1000 exup from UK, 27k miles .
i notice that the engine bogs down very easily south of 3k rpms. once i hit 3k or so, maybe 3300 or something, it comes back to life and has begin to accelerate. but at the lower rpms, it just dont want to go.

- No problem with start engine, warm or cold
- Exup valve removed (its damaged, a lot of rust, dont want to move, servo motor OK, connected, runs)
- Spark plugs and coils OK, i see a spark clearly on all cylinders
- Air filter , clean, K&N
- fuel filter clean, fuel pump seems to working (when i turn ignition on, and hit run button i hear quietly "cllick,click,click - click,click - click" and quiet. Is that normal?)
- carburetor -dont know, maybe dirty (there is a little rust in the tank)

Below 3000 up to redline there is no running problem, accelerated very nice, and it has good power.

Please help me, any suggestions how to fix this?
Is a reason a broken Exup?


Sorry for ban english,
Martin

[DonTZ125]

Hi, Martin.

Welcome to the madness! Don't worry about your English - you're doing better than some of the rednecks we get around here!


Your power issues below 3000 are almost certainly due to the EXUP valve. If the servo is still good, get yourself some fresh cables and clean up the valve itself. See this site for some great info - http://www.cartestsoftware.com/fz1/exupmaintenance.html.

The fuel pump runs for 5 seconds when you turn the power on; this makes sure the carbs are full of fuel when you try to start.

If you have rust in the tank, even an little, I would drain and clean the tank, the screen in the tank, and the carbs. Replace the little fuel filter between the tank and the pump.

[sweekster]

[asphaltsurfer]

Thank you very much for your reply!

I saw this site. FZ1 has very similar exup cover. Do you think that exup valve and the exup cover from Yamaha FZ1 (FZS?) matches to FZR 1000?

my exup is in very bad condition and i'm afraid that i must get new one. Cover is nearly welded to valve axis, I applied on it couple things but they have done nothing.

What do you think?

[sweekster]

Not sure about the FZ1. You may have better luck with the 99-01 R1. I know for sure the exup cables are the same as I'm using R1 exup cables on my 94 FZR1000

[dan83590]

The exhaust manifold and valve was the same for all the FZR EXUP's 1989 - 1995

The cables and servo was the same for all the RU's (from 1991-1995)

The YZF 750 uses the same valve/end plate/pulley wheel etc but the manifold itself is different.

The early R1 and the early Fazer 1000 uses the same end plate/pulley/ cable bracket and shiny cover but the valve and manifold is different.

I pinched this info from another forum.

[asphaltsurfer]

Big thanks!!!!!!