Ok, well I took my bike to work the other day and on the way home when I wrenched it she stuttered then caught, I figured it was just cold and kept going. Well anytime I hit the throttle she stuters, I dont think its the carbs as I run her regurally through out the winter. And it rolls out just fine, she stutters randomly at different throttle positions and as a side note she idles just fine, and has had the coil over conversion. It felt like it wassnt getting electricity, I have felt gummed up carbs and I am pretty sure it wassnt that. I am thinking its the dreded R/R is going so I will report back in about 20 min with a reading at idle and a reading at 5000 rpm.

Mike

idle cold fluctuates rapidly between 12.02 - 12.15
idle warm fluctuates rapidly between 12.15 - 12.22

5000-5500 rpm cold 15.30 steady
5000-5500 rpm warm 15.36 steady

 

From your test results Mike it doesn't look like the R/R.

Have a look at the wiring on the stick coil conversion. Make sure the wires haven't chaffed through shorting out a cylinder. Perhaps run it for a bit and feel the headers, a cool header indicating the problem.

Cheers, SB

 

I did check headers with water all sizzled. Maybe a bad battery?? or could be carbs I can pull em easily.

As a better description, when it stutters it chuggs along for a bit like 3 seconds then the bike catches like normal and is off like a rocket. its really wierd, only thing I have done recently is an oil change with rotella 10w-40. But she rode fine for two days before this started. I even put seafoam in for extra measure.

Ok, I opened up the carbs and they are all clean. so now I dont know.

Maybe i could clean my K&N filter, that could maybe help.

will report back later...

Well, it was dirty but now i have a dead cylinder, and its smoking. So now i am gonna get some rest, then tomorrow try n figure out more. Any tips ideas or suggestions are greatly appriciated.

Mike

 

Anyone???

Btw i swapped a coil with a known working coil(hot header). And still was cold. Well ill run it after work then pull the plug to see if its wet. Will report back later.

 

If the coil is known to work have you checked the wiring going to the broken cylinder mate?

 

Could it be something simple like a faulty plug - I've had it happen...............
It's not the R/R

Water in the fuel could also cause a stutter, especially under load, but I'd be looking at needle and seats in the carbs, and float height. Maybe.

 

Ok, well it was low on fuel. So i ran a can of seafoam in it, that didnt work so i filled it up and still nothing. That was before i took the carbs off. Ill get new plugs as i am sure with coils it could use new ones. I will try and do a spark test if the weather dries up. Then ill go from there.

 

Ok, she has spark, jumps a 1/4 gap. Not a bright blue snap, but it does snap. I got new plugs, nothing, put old coils back on, and nothing. No oily residue on plugs, smelled like fuel. And why n the hell is she smoking??? I hope its not a head gasket. Oil looks fine not milky, but could it be leaking into the cyl only? Man im getting worried now. Ill pull carbs again tomorrow to ensure the floats are seating correctly. Oh as a side note i think my batt is dying, the headlights will stay off after starting untill i rev it for a bit or hit the starter to charge it a bit more. Will a faulty batt cause these symptoms?

Mike

 

A bad battery can cause all sorts of problems Mike.

See How to diagnose electrical problems, charging system on your motorcycle

Did you charge the battery before starting the bike? The CBR1000F loooooooooves a fully battery.

Cheers, SB

 

Well I hate to say it but I am pretty sure it is either bad rings or bad head gasket. she is spewing out lots of smoke, and chugging badly. I guess Ill start looking for a parts bike or a good motor and do a swap, or part her out. also oil is comming out of the exhaust weep hole. oh the cold cyl was cause I forgot to screw in a jet. Let me know what you think. Oh I tried to do a compression test, but my tester doesnt fit the spark plug thread.

mike