04 FJR bogs down, sluggish throttle after stop and go city riding?

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gbasky

Member
Joined
May 25, 2014
Messages
16
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Location
Saskatoon, SK CANADA
Hi fellow FJR'ers...

Can anyone shine any light on this behaviour by my bike (an '04 that had 58,000kms when I bought it in June and now has 68,000kms).

I have never run into this riding on the highway but it has happened several times towards the end of longer cruises, with stop and go riding, around town.

As relatively new rider and bike owner, I'm not sure what the proper terminology is to describe it:

- starting from a stop, there is significant delay in response

- I need to get the revs up higher than I normally would to start moving

- it almost feels like the bike is going to stall

- it seems like it's having trouble "breathing"

It did exhibit the same behaviour on one "highway" ride this summer, on a steep, twisty piece of road in the Black Hills (South Dakota) -- either Iron Mountain Road, or Needles Highway, can't remember which one -- where my speeds were low and fair amount of braking.

What say you? Any Gen 1 owners out there experience anything similar?

Thanks

Greg Basky

Saskatoon, SK CANADA

 
The first thing to consider is your idle speed. Gen 11 are set at 1100-1200 RPM with the engine fully warmed up, not sure what the Gen 1 should be set at, but I'm guessing it won't be far off that.

 
Couple of things to check:

As mentioned, warm idle RPM

Make sure a rodent hasn't built a nest in the air box.

Check throttle body sync

Perished / cracked vacuum caps on the TB's

Plugs, plug cap breaking down

High resistance on the ECU plug.

There was a post about the LT lead on a coil shorting out.

Just fixed a mates bike with a clogged tank breather hose, pressurized petrol tank.

Started OK when cold, ran like ********** when started warm.

 
Next time it happens, stop and open the tank filler door. Is it under vacuum? If the tank isn't venting properly, you won't be getting good fuel feed. This would be expected to be worse after a period of higher fuel consumption (highway run). There have been cases where tanks have collapsed under vacuum!

 
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