Sputtering, stalling and cut out
 

My first bike ever. 95 CBR 600 F3 w/ 47k miles on it.

Today (day 2) all freeway for 8 miles, it suddenly feels like something is sucking the life out of the bike, I downshift and same thing. Pull the clutch and motor dies. Push it for 5 mins before trying a 3rd time, and boom! Starts right up like nothing ever happened.

At lunch, I reached my destination, backing it up to the curb, it cuts out.

Rides home like a breeze 12 miles on freeway.

Other things I have noticed.

When I hit the throttle it has a brief stutter like it’s going to die out before revs (in neutral at idle, warm or cold.)
When riding and really giving it gas, sounds like it’s spitting and it’s not consistent. When letting go of the throttle at high rpms, does a lot of little backfires.
Smells like gas almost always.

Where do I start?

Is this carb sync trouble? Bad plugs? (I’m replacing plugs today and anything else I think sounds viable from replies I can get.

Also, what’s the deal with the gas “on “off” “res” on the side. Is leaving it on res a bad thing on a full tank (aside from the face it may defeat it’s purpose)?

Thanks everyone!
Joe

:icon_omg:
Had this happen on my superhawk, i mean exactly the same! (v-twin i know)
I changed the plugs and ran like a champ. Same problems occurred year later, fixed with same solution. Never really pin pointed the exact cause, but the new plugs worked everytime! hope this helps brother....

smelling gas tells me its running ritch

running on res. isnt going to hurt anything but then if you run out of gas, thats its, your out....ya should always run on the "on" position and if you run out of gas on that, switch to the "res" then ride to the nearest gas station and fill up.

Hahaha, ran out of gas 15 mins after this post with no reserve. I have it ON now. Thanks

I only got 60 miles on a tank :/. Might be rich and plugs. Thanks so far.

If you tank up and are still having trouble, check out the regulator/rectifier.

Inspect the connector, as well. Look for signs of heat-related damage.
Melted plastic, burnt pins, bubbly wires.

Check the r/r, is it a smooth-fill epoxy? if you see any cracks or bubbles,
it's going bad or has failed.

If so, the coils aren't getting sufficient current and can't fire the plugs.
Hence mis-fire and rich gas. After the r/r cools down, it works again.
Till it heats up, rinse and repeat.

Here's my favorite links, for a heads-up on the issue...

Charging System Diagnostics - Rectifier/Regulator Upgrade - Triumph Forum: Triumph Rat Motorcycle Forums

https://cbrforum.com/forum/f2-tech-9...-solved-27739/

Technical Resources - Resources for Electrical Systems on Motorcycles and ATVs - ElectroSport

Hope this helps, Ern

Well, new plugs, old were black, and starting to corrode. #2 had a little oil on the plug, stuck my finger in and didn't get anything. #3 reaked of gas.

Once it was all back together I started her up and heard a ticking, my first thought, was a valve. Well, at idle throttle jumped up to 8k rpm on it's own for about 3 seconds, when i gave it gas it came back down. Idled fine after that. Still a small hesitation when tapping the throttle at idle.

Took it for a spin, rides much better, first gear is still kinda rough. If I'm on it (accelerating quickly) though, sounds much better.

But of course I had to screw up something. Got home, let her idle 3 or 4 minutes, when I went to turn it off, the fan was on and it was running pretty hot. Didn't touch the radiator and it has plenty of clean fluid.

I'm riding it to work tomorrow, wish me luck.