The Honda Owners Club

Hi, I have a 1990 Honda CBR1000F-L. When I purchased it second hand I rode it about 70 miles and filled up with petrol literally half a mile from my house, and then rode home. A few days later when I went to use the bike it would not start and over about a 6 week period having changed the plugs, battery etc and generally played around with it trying to jump start it from my car I took the petrol tank off and drained the petrol which I then transferred to my scooter... which immediately started to splutter and I realised it was dirty fuel! Having refuelled it it started almost immediately (from a jump start) but every since it has had trouble starting on the its own battery (very lazy engine turning and then it will eventually fire). But the worst thing is that it now won't start when it is hot! You press the starter button and nothing happens and the ignition lights just go dim (although all the other electrics work, ie indicators, horn hi and low beam!). When it eventually cools down (ie cold) it will start, but again very lazily! I have changed the starter motor for a second hand unit and also changed the starter relay and the regulator/rectifier (again second-hand units). But this has made no difference. It will start fine on a bump start when hot (virtually the second you release the clutch) and once it is running all the electrics work fine and when you rev from tick-over with the lights on they will get brighter. When cold, the lazy turn-over is worse when the choke is out so I usually keep the choke in until the engine rotation eventually picks up and then put the choke on and this seems to work. I have also checked the battery connections etc for loose/broken connections but there is nothing obvious!

Do you have any idea what the problem may be? Could I have over-loaded any of the electrical components by jumping it from my car? One last thing, I notice that my key ignition switch is sometimes a bit temperamental; when I turn the key I sometimes have to jiggle it before the ignition lights come on! I then jiggle it a bit more to ensure they don’t go off and then proceed to start it.

Many thanks for any advice you may be able to provide.

Best regards, Indiemegs

You haven't mentioned it as such, but is the 'changed' battery a brand new one? If the bike started easily when you 'jumped' it from the car, then it could point to the battery. The battery may be able to illuminate the lights OK, but it may not have the 'cranking power' to turn over the engine fast enough to start the bike. Starting draws a lot of current, so if the battery is suspect, it may not be able to deliver enough, whilst being able to work lights etc.
If you have a multimeter, check the battery's voltage. It should be 12.5V+, but even then, an old battery may give this, yet not have enough power to start the bike. If it is a brand new battery, then it does sound rather odd. You would notice the difference a new battery makes if the old one is getting a bit tired.

Also, it sounds like the ignition switch is getting a bit worn, but it can't be the cause of your problem if you do get the starter to work, albeit not very well.

Hi again Red V Four, I have been searching the internet and had another look at my manual and I agree with you that the first point of call should be the battery (as I did not maintain my current one over the winter and suffice it say I think it is dead!). I am therefore going to buy a new one and was thinking of a VARTA.... or do you have any other recommendations? This should take about a week to arrive as such and charge etc so unless I hear from you re: the battery recommendation I will let you know whether this is successful next week. Many thanks one again. Indiemegs.

I think Varta batteries are OK, as it is a well-known make, but the general opinion seems to be to go for Yuasa. Don't buy a 'cheap' one of an unknown make, though. Is it a CB14L-B2 ?
If you have one, charge the battery with an Optimate (or similar) first, before fitting it. This will give it a good start in life, and it will be as good as it's going to be before you use it.

Thanks for the recommendation Red V Four, I have now ordered a replacement Yuasa battery. Will let you know the outcome once received and charged. Best regards, Indiemegs

12.5 volts is the minimum charge that a battery should have....13 to 14 volts if the battery is in top condition

Witch

Witchmaster wrote:12.5 volts is the minimum charge that a battery should have....13 to 14 volts if the battery is in top condition
Witch

Haynes state: "a sound fully charged 12-volt battery should produce between 12.3 and 12.8 volts", and I must admit, all the new ones I have ever had, once fully charged and 'rested' for an hour or so before fitting, have never given more than about 12.8 volts. I've never known a 12 volt battery to measure 14 volts, unless literally just taken off charge!

Have you got that new battery yet, and if so, has it improved the starting?

Hi, yes, arrived on Monday. Have now charged as recommended and I put it on the bike only a few hours ago! Initial results are encouraging as it is starting much better although it still turns over very lazily for about 10 seconds until it kicks- in properly and then starts fine. The bike is in the garage and I haven’t had time to take it out onto the drive yet to allow it to warm up to check whether it will start when hot. I probably do this on Friday afternoon or else over the weekend!

I note with interest the comments on battery voltage, so I checked it immediately after charge and it read 13.65V, once on the bike and after a few starts it read 12.65V.

Thanks for your help and advice so far. I will post the results of the hot start as soon as I have tested.

Fingers crossed then! 13.65V just off charge is a pretty typical voltage. If after charging, it's left overnight, you would get something more like 12.8 (or thereabouts). After starting a few times the voltage will drop, but you will find that the voltage will recover on it's own somewhat (but only up to a point though). Bear in mind that if you keep starting the bike without actually taking it for a decent run, you will eventually discharge the battery enough so that it will not start the bike. You really need to take the bike for say, a half-hour ride, come home, and then try it for it's hot start. That way the charging system has been working at it's optimum and recharged the battery, and not just running at tickover or just above. I always turn the lights off to start my bike, so that less current is drawn on starting. (I believe some new bikes with headlights on all the time have the headlight momentarily cut off whilst starting to minimise load on the battery.) Bike batteries are really quite small compared with car batteries, so you can't take too much out of them before you have to start putting something back in!

Tested the bike this afternoon and the problem appears to have been resolved. The bike is currently off the road at present therefore I am unable to road test it so I started it up on the drive (still a very lazy starter motor action for the first 5-10 seconds before it picks up and starts). Let it tick over until fan kicked in and then turned it off. All attempts to start it again thereafter were successful, although the lazy starter motor action prevails each time for the first 5'ish seconds. Previously, it would not start when hot under similar conditions (the starter motor would not even turn) therefore I am hoping the problem is cured…. although I must admit that I didn’t think it was going to be resolved by simply buying a decent battery!

I now aim to get the bike MoT'ed over the next few weeks and then I'll be back on the road, therefore a big thank you for all of your advice.

PS. Battery is back on charge via my Oximiser.