Help! Dead F650GS near Fortaleza (Brasil)

**Smellybiker** · #1 26 Jun 2005

Anyone know what this problem is ?

Symptoms began as poor starting & bad idle and have got progressivly worse.

It now has barely runs, backfires, dies below 2000rpm.

I've recently changed the spark plug, fuel filter / pressure regulator & air filter as part of a bloody good service in Buenos Aires.

I suspect its been poisoned by lousy fuel so have drained the tanks, the old gas didn't even SMELL flamable !!! It didn't help, but was a good thing to do.

I'm starting to suspect things like fuel injectors, the injector nozzle and fuel pump, although the fault could be in the ignition system somewhere.

Any help, ideas or suggestions would be very welcome !

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Last seen in S.America, missing presumed fed.
http://worldtour.overpro.co.uk
http://www.motodogging.com

**Grant Johnson** · #2 27 Jun 2005

Did the problem start shortly after the service, or after filling up a few thousand k after the service?

Still SOUNDS like bad gas - and if it's really bad, clogged the injectors.

I'd concentrate on the fuel system, although it would be nice to know a little more - as above.

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Grant Johnson

Seek, and ye shall find.
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One world, Two wheels.
www.HorizonsUnlimited.com

**Smellybiker** · #3 27 Jun 2005

Thanks Grant.

I found the problem, the intake manifold had blown. There was a big U-shaped crack in it.

When the engine was running the vacuum would make a 'flap' open up, letting air in and screwing up the mixture. Scary stuff when it backfired while I was poking around looking for air leaks !

Off to find (or make) a replacement part. Thanks again.

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Last seen in S.America, missing presumed fed.
http://worldtour.overpro.co.uk
http://www.motodogging.com

**Grant Johnson** · #4 27 Jun 2005

no worries, not that I helped a lot!

Good spotting - leaky intake manifolds can be tricky to spot.

At least I got the mixture/fuel system part right...

**Smellybiker** · #5 27 Jun 2005

I'd like to claim excellent powers of observation, but alas I cant.

The bike backfired while my face was a few inches from the manifold. The bright flash gave a good clue, as well as scaring the crap out of me. ;-)

Cheers,
Bob

**ozhanu** · #6 27 Jun 2005

I had the same problem since a month. Same symptoms (began as poor starting & bad idle and have got progressivly worse / barely runs, backfires, dies below 2000rpm)
And also I've fully serviced 2 weeks ago (hanged the spark plug, fuel filter / pressure regulator & air filter)
Btw I have a 97 make F650.

Thanks for sharing your problem and solution with us, I hope it will help me a lot.

thanks

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ride safely
ozhan u.
www.ozhanu.com/gezi

[This message has been edited by ozhanu (edited 27 June 2005).]