CBR600F Loss of power juddering, coughing and spluttering

Motorcycling
1

Hi all, hope you can help.

I am the proud but concerned owner of a 2001 CBR600F. It’s currently got 21k miles on the clock, and last had a service at the 20k mile mark.

All was fine, until earlier in the week. I only bought it recently and having only ridden around 200 miles on it I ran the petrol down low enough that all 4 bars on the reserve indicator were flashing by the time I got to a petrol station. A few hours later I took the bike out again and it’s started intermittently juddering and spluttering, dipping in power in a jerky manner. Sometimes it happens only at 10-30mph, sometimes only around 60-80+mph and sometimes the whole way through the range.

If I hold the throttle steady, the power will dip. Sometimes the rev indicator blips up and down to reflect the decrease in power, and sometimes it seems to stay the same. The blips are fairly constant while I try and hold that speed, each one around a quarter of a second. (think jud-judd-judder etc!) but if it’s happening at a slow speed then I can usually power through it and it’s fine at a higher speed.

Also, when it’s really bad, if I pull back fully on the clutch or drop it into Neutral then it will cut out. It’s one of those problems that every time i’ve asked someone to see it, it usually doesnt happen - but I would say it occurs around 10-20% of the time the bike is started.

Anyone got any suggestions? I was tempted to say I’ve dragged some gunk up from the bottom of the tank, but i’ve been told that the fuel injection would filter that out.

I’d done a good 50 miles since the problem occurred, and it’s not gone away. Sometimes the bike is fine for 10-15mins, and then sometimes it’s so bad that I can’t pull away.

I’ve filled up with fuel since, and at the suggestion of a friend put a little redex in, but nothing has helped so far.

Am I going to have to take it into a Garage? I was hoping to do a 300 mile round trip over the weekend - my first big run since buying it, but I’m concerned i’ll do it some damage. Unless anyone can recommend a quick fix, does anyone have any recommendations for a mechanic in East London that won’t rip me off? (I have a terrible track record with garages overcharging me…)

Thanks all!
Simon

2

Hi, if you gunked up some injectors with stuff from the bottom of your tank when you run it very low the problem wouldn’t occur 10-15% of the times but all the time.

Was the last service from a Honda dealer and the owner’s book got stamped proper ot not?

Personally I’d take it to Dobles to sort out any Honda but they aren’t cheap so even before that I’d get myself a Haynes manual, a new set of HT leads + Spark Plugs + Air Filter and Fuel Fiter and change them myself. At least you know for sure the new parts have been replaced on the bike.

Start by buying and replacing the fuel filter first before you splash out on the other parts, I think that would be the first thing to be messed up with stuff from the tank.

Then if the problem persists you know the issue is somewhere harder to deal with which might need their diagnostic stuff in which case do what you need to do to save some money to afford a proper Honda mechanic to sort it.

Too many times I’ve tried to cut corners to save a few pounds only to find myself having to get real branded parts and/or taking my bike to a dealer’s garage eventually spending more money and wasting more time.

Places like Dobles will also sort you out a loaner bike while yours is getting fixed, I’m sure other (local to you) Honda dealers will do the same if you ask them.

Good luck.

3

Hey sounds like a prob I had a few months ago on my now binned CBR600. Took it to SBK and they diagnosed gunked up throttle bodies which after they cleaned them sorted the problem. Thought that I had a bad batch of fuel at the same time after similarly running low, but a service and the cleaned throttle bodies saw it running far better.

By the way I have a Power Commander for sale that fits your bike, made a massive improvement in throttle response and middle/top end performance. Takes 20 mins to fit PM interested.