Hi I'm currently having some trouble with my F1, on the way back from a trip the other day my bike died on me, and refused to start, as if the engine was flooded. The day after it started but doesn't rev past 4000,and coughs and splutters. I have changed the spark plugs to no avail, and have also checked the fuel pump works. And am now a bit stuck for ideas. Any help would be greatly appreciated.

 

Could be a fuel delivery issue, but I would first check your voltage at the battery while it's running both at idle and revved up to 3-4k or so. The regulator & stator are somewhat common failure points on these bikes, and when the voltage into the CDI isn't correct the ignition system will create problems like you are describing. Since it's the easiest place to start I would check this first.. post back with your voltage numbers and we can go from there.

 

Have checked battery, and it's reading 12 whilst idling and rises to 13 when revved, what's your thoughts on one of the jets being blocked?
Also when changing the plugs, number 4 seemed slightly wet.

 

It's possible something could have blocked one or more carbs, but the filter should normally catch any debris coming from the tank before it gets inside. The only way to know for sure would be to pull the carbs and clean & sync them. Could also be a stuck float or leaking needle causing overfueling. Is there any dark smoke coming from the exhaust while running that would indicate an overly rich condition?

You said you checked the fuel pump operation so that shouldn't be the issue. I would also verify you have good spark on all 4 cylinders while cranking the bike over. The CDI doesn't normally fail, but a weak or failing coil would be another possibility. If you have access to an infrared/laser temp gun check the header pipes while running to see if any of them are a lower temp than the others to help isolate the misfire.

 

Your voltage is too low. Should be 13.00+ near idle. Check reg/rec connections first, possibly replace. My F1 did the same last summer. Wouldn't rev. Found reg to be bad. Replaced and all is well. Hope this helps!

 

thanks for everyone's help on this issue, unfortunately I threw in the towel this morning and took her to the garage. They seem to also think it is electrical, weak coil or faulty regulator. I will keep you updated when the problem is sourced!

 

garage seem to think it's the cdi even though they've not even put a tester on it yet. Not too sure myself. Anyone got any ideas on the price of one? I've heard they're not cheap!!!

 

The CDI box will shut off if voltage drops below a certain point. It like someone reaches over and flips your kill switch. Best bet is off ebay.

Try this before you start throwing parts at the bike. Hook up a fully charged car battery to the bike. Start her up and run the engine through it's rev range. If it works no problems the issue is the charging system. If it still cuts out start checking all the connectors for corrosion.

 

That's a good idea with the car battery. I forgot to mention before, but make sure to take a good look at the connector between the stator & wiring harness. I had a corroded high resistance connection there and it caused my connector and stator wiring to start melting before I realized there was a problem with the charging system.

I would not throw a CDI at it until you can be fairly sure that's the problem since they don't fail very often in my experience.

 

Unfortunately the bike is in the garage at the minute, awaiting a used CDI unit to be delivered. They seem to think that because the tachometer stopped working, when the problem started but is now working. That it burnt the CDI unit out?? Does this sound at all plausible?