Topic: Startup problems

[Luythen]

Hey

The last few weeks I have experienced increasing startup difficuties with my bike, as well as poor idling skills.

I can pull the choke start the engine and it will run for four seconds or so, sometimes the carbs backfires a bit, but then it will die out. When I following this try to start the engine againg, I have to keep turning the starter engine for several seconds while the motor starts and stops in short intervals, again sometimes backfirering.

Any idea what this can be caused? is it my carbs that needs a sync? or do I need to look at the whole electrics?

Sincerely
Henrik

[TwoTired]

Probably would be helpful to know what bike you are working with.

But, generally speaking these bikes need tuneups every 3000 miles or so.  Many performance and run issues can be cured with a thorough and complete tuneup.

Fuel contamination? 
What is the condition of your spark plugs?

[oldbiker]

For reliable running you need:- Petrol (in the correct mixture)  Spark and Compression. If compression is OK, clean points and plugs and check connections to coils etc. If these are OK then check carbs for cleanliness. ie. no dirt or water in the float bowls or jets. It is always advisable to have a filter in the fuel line.

[Luythen]

Sorry i keep forgetting to name my bike in here

It's a cb 500 four

So just a thorough tuneup, is probably what I need?

I suspect that the problem is that water is getting through here and there. so I'll just have to dry it out and try again.

[eldar]

Check points for pitting and timing.  Also check plugs after it dies to see if you are running too rich or lean. From my work on my 78K, I would get backfires and short idle times when I was running super rich.