Hi,

Absolute bike novice in need of some advice; I've finally got a license buy my F2 only seems to want to give me fun in bursts - please help!

I have a '93 CBR600 F-P, which for one reason and another sat completely still without being fired up for 10 months; on passing my DAS I could hardly wait to put this bike on the road and get amongst it. Got the bike serviced and MOT'd in on 21st October last year - two days of riding later the battery was completely discharged and couldn't be rescued by my charger. Looking under the seat it was clearly cooked so I bought a new battery and replaced the regulator/rectifier - this resolved the battery problem.

Since then though, the bike has problems starting, which I initially I put down to the cold weather and my being a muppet with a manual choke. Back when I needed the choke, the problem was that generally it'd fire up and settle to what seemed a comfortable idle, but giving it any throttle at all killed the engine. Then it was very reluctant to restart - it'd turn over until the battery died, but only rarely would it catch; if it did though, it would *usually* run okay after that. I wondered if I was flooding the engine and causing the problem, although I couldn't get a strong smell of petrol so am not sure.

Now that it doesn't need choke to start, or at least very little, I find I can ride away on it, but on about 50% of journeys (and rising, I think) the engine will die within the the first half a mile when the revs get too low. Today I could feel it struggling even though I was trundling along at 30mph (just over half a mile into the journey) and then it just cut out - I bump started it while it rolled a halt, but it died again. Both today, and on those previous no-go journeys, once it's dead I can't get it to restart. Again it'll turn over till the battery dies, but no catching at all. After spending the night on the charger I can rinse and repeat, with seemingly a 50/50 chance I'll get beyond half a mile. Yesterday was odd in that after covering a couple of miles in town, the revs started getting much higher than I'd expect - instead of idling at ~1500, it seemed to go up to ~2200 but would settle there. Resolved it by tweaking the idle speed ****, but this was unusual even though it did let me get where I wanted to go.

Back when it needed choke and now that it doesn't, provided it gets past half a mile it does seem to run fine. Indeed, from my very novice point of view there is nothing to indicate a problem once it seems warmed through and is on the go. Perhaps worth saying that generally after a mile I'm on B roads at about 45-60 pretty consistently for at least 10 minutes. So, I'm wondering might any of the following be true:

1. The spark plugs are responsible and need replacing?
2. The carburettors need stripping and cleaning?
3. Have I put too much redex in, in the hope of cleaning the carbs?

Any advice much appreciated - riding was/is such a pleasure but right now it seems pot-luck whether or not I'll be pushing it back to the house in the morning!

Thanks,
Mark

 

I'm thinking you should re-visit the r/r. Do you have basic electrical skills?
Can you use a multi-meter, do you have one? If so, here's a clear how-to on
checking the charging system and figuring out if it is all performing properly.

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

On another note, Check the fuel-filter and petcock filters for blockage/clogging.
This is a little more of a reach, but easy and it never hurts to give them a little love.

Ern

 

Thanks Ern - I hope to get the tank and check/clean fuel and petcock filters at the weekend. Forgive my ignorance, but are the not the same thing on the F2?

Why do you think it could still be the R/R? When I had a problem with that before the battery had very clearly cooked and it also wouldn't take and hold a charge; that's not the case now and even when it won't catch it'll at least turn over for a good five minutes (it feels like). I guess it could be non-obviously broken with different symptoms then.

Thanks,
Mark

 

Most of the symptoms match, and this is the easiest, cheapest way for you to start
figuring it out. Follow the link, check the system and determine if it is/isn't the issue.
Then we can go on from there. If I list an entire flow-chart of possibilities, I would be
spending a hour per post. That would limit my ability, to assist all of the folks I would
like to. Fuel/carb problems generally aren't "on/off", if it's related to those issues the
bike runs like crud, all of the time.

Hope this helps, Ern

 

Check your choke operation too, really you should not need to be adjusting the idle screw - I'm thinking the choke is sticking potentially..... my 2 cents

 

Yep... I was going to mention the sticking choke as well. That is my bet.