just bought a RVF400 - failed on me this morning

[Enzymer]

took delivery of the bike last night. all was good, took the bike for a spin after the previous owner dropped it off and it felt great. No problem starting it. However, this morning it was a real pain starting it. Starter motor sounded really weak comparing to my CBR250RR and it wouldn't turn over. When i did a rolling start i finally got it going. After 5-10 minutes riding, when riding relativity slow I suddenly lose power. i found a parking spot for the bike and i try to start it but it won't start, the starter motor sounds really weak...

what could this be? do i need a new battery or could it be some electrical problem?

[Cammo]

It sounds like the battery has insufficient charge. This could be because the battery is in need of replacement, or it could be because the charging system on the bike has issues.

Remove the whole tail unit, charge the battery and get the bike going (or use jumper leads and a car if you need to), get hold of a multimeter ($10 at supercheap) and there are some really simple checks you can do while the engine's running to determine where the fault is. There's no point throwing money at any parts (new battery included) until you've found what the fault is.

This is a common problem, good news is that it's relatively easy to sort.

When the engine's cold and until you become familiar with the bike, make sure you're starting it with FULL choke and NO throttle. Any other method can flood the plugs and it will never start.

[magg]

As Cammo says save your money until you know wants wrong. Measure the battery voltage once you get the engine started. Should be 14-15 volts DC at 5000 rpm.

[Enzymer]

It sounds like the battery has insufficient charge. This could be because the battery is in need of replacement, or it could be because the charging system on the bike has issues.

Remove the whole tail unit, charge the battery and get the bike going (or use jumper leads and a car if you need to), get hold of a multimeter ($10 at supercheap) and there are some really simple checks you can do while the engine's running to determine where the fault is. There's no point throwing money at any parts (new battery included) until you've found what the fault is.

This is a common problem, good news is that it's relatively easy to sort.

When the engine's cold and until you become familiar with the bike, make sure you're starting it with FULL choke and NO throttle. Any other method can flood the plugs and it will never start.

thanks mate! very helpful. just a question: if i have flooded the plugs, how can i fix that?

[Cammo]

Plugs can sometimes (not always) be revived by taking them out of the cylinders. To take them out you'll need a deep/long 13mm socket - not usually included in most socket sets - and an extension bar. You can get the rear plugs out easily with the tail fairing off. For the front plugs you need to undo the bottom mounting bolts on the top radiator and swing it out of the way, space is tight. Let the cylinders dry out for a few hours and dry the ends of the plugs over a gas flame. New plugs are around $100 a set...

Or you can just leave the bike overnight and hope it dries out somewhat, sometimes works.

The starter motor should turn over at about the same rate as your 250, the engine may not start if it's not cranking quick enough, this could be your issue. You should fully charge the battery and try and start the bike before you tackle removing the spark plugs - try the easy solution first.

Sounds like you'll be getting to know this bike fairly rapidly!

[Enzymer]

just a quick one: One the left handlebar of the RVF400, isn't there supposed to be a switch where you can turn on and off the headlights? Like on the CBR250RR. The reason i'm asking is because on my RVF400 there is no such switch. The headlights are always on, and the only thing i can do is to switch from high beam to low beam.

[magg]

RVF400 are lights on when ignition on, no off switch. Headlight turns off when starter button is pushed, to ease load on battery. Pull the headlight fuse to take the load off the battery while you are trying to start it if the battery is suspect. Also bump starting works if the battery is a bit weak.

Plugs might not be fouled so mach as the battery is weak. You might find bike will start ok with a good battery, NC30/35 can be finicky starters and appreciate a well charged battery.

[speedy231278]

I've always found that if for some reason mine either doesn't start fairly quickly, or if for some reason it stalls after less than about 30 secs running from cold, it'll often completely refuse to start unless you leave it for five mins or so. A well charged battery will also help. I never thought there was anything wrong with mine, the bike always started fine if you got everything right, but if for some reason starting was cocked up and a few attempts were needed, the battery became weak very fast, so if the bike was reluctant to start I would occasionally end up with a flat battery. Eventually I stopped being a skinflint and put a new battery in. The difference was ridiculous. The starter kicked over probably half as fast again, and on the very rare occasion it's taken more than one attempt to start the bike, there's been no suggestion of it getting tired very easily if at all.

[speedy231278]

Also - if the battery was weak and you were riding slowly, you may not have been charging sufficiently regardless of the state of the charging circuit, as as you say, you cannot turn the headlights off on an RVF, which isn't an issue when everything is happy, but won't help matters if you have a slight issue somewhere. The output of the charging circuit is highest at 5K rpm or more, at very low revs it is a few volts less. There's loads of threads on here to do with dodgy charging circuits and how to test and fix them, so do a quick search and you'll find all the specs, and what to do if the output is lacking.

[Sam-NI]

I bought a bike and it failed a couple of days after I bought it in similar circumstances! Don't panic, just do as these guys tell you, and you will be up and running in no time.