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Discussion Starter · #1 ·
My cx500c run very well after restoration/carbs rebuild, for about 4000 km until recent weather change.
I keep it outside, temperature drops around zero in the night.

Several days ago I started bike and did a few km and I noticed engine drown oneself, loosing power in 3k-6k rpms. Yesterday It get worse, I did about 4 km and engine died. I can start it but it runs in very low rpm, doesn't react on throttle.

I am away from my garage. Is there some quick fix for it?

I will check spark, fuel line etc first and then I will take out carbs and clean it.
 

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Battery dead?....not accepting charge..?
That would be the first to check..
When i had my bike outside some years ago in cold it would refuse to start for ages til the battery was giving out/starter clicking...all solved once garaged.....
 

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Discussion Starter · #3 ·
Battery dead?....not accepting charge..?
That would be the first to check..
When i had my bike outside some years ago in cold it would refuse to start for ages til the battery was giving out/starter clicking...all solved once garaged.....
"I can start it but it runs in very low rpm, doesn't react on throttle."
 

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Open the drains on the carbs....close,refill the bowls to flush out......
Did your rebuild include a new Cdi/ignitech....i cant remember
 

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Run the stator test.

A failed 5/9 will give a reluctance to start and a reluctance to rev in some cases. It stops generating enough power to do any more than this.

Are the spark plugs black and sooty or?
 

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Discussion Starter · #6 ·
will have look after the weekend, thanks for tips!
 

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Discussion Starter · #7 ·
ok, problem sorted: my air filter (new also around 4000 km) was blocking airflow to carbs. By the way did you have a similar problem with air filter to block air flow completely after so short time? Is it normal? Should I just pressure air clean and use it again in or is it another: now f***** 5 minutes - used to be long lasting part?

Please enlighten me.
 

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If you are getting blow by from the crankcase the oil filter may be getting oiled. Have you opened and drained the drain tubes from the air box?
 
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Discussion Starter · #9 ·
If you are getting blow by from the crankcase the oil filter may be getting oiled. Have you opened and drained the drain tubes from the air box?
that is something I need to verify but after first inspection filter is dry. Thanks for tip. Cleaning old filter with air will help?
 

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Is it a std filter? Is oil or milky residue evident in the airbox?
4000km wouldnt be expected to block a filter on sealed, no dirt, roads.....
 

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Discussion Starter · #11 ·
Is it a std filter? Is oil or milky residue evident in the airbox?
4000km wouldnt be expected to block a filter on sealed, no dirt, roads.....
dont know what std filter means: its paper filter, black dust looks normal, normal use, mostly city, some summer trips.
 

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Std=Oem...but many would use aftermarket like Hiflo-filtro again 4000km a gentle tap and compressed air from inside of the filter would be precautionary....ie extra maintenance...not be expecting to affect performance
 

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Discussion Starter · #14 ·
it is hiflo, I have also high consumption of fuel around 6.5 l per 100 km, its 36 mpg (us) I have balanced carbs, no air leaks, all seems look correct. I am thinking about running bike for next 200 km without air filter to see if this filter affects my fuel consumption . I have steal mesh inside airfilter box to stop dirt going into carbs. What do you think?
 

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A blocked filter restricts airflow. You know this.

Restricted air flow increases vacuum causing more fuel to be lifted through the jets giving higher fuel consumption.
 

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a gentle tap and compressed air from inside of the filter would be precautionary
Blow compressed air from the OUTSIDE of the filter. In operation, airflow is from inside to outside, so dirt will collect on the inside of the filter.
 
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Discussion Starter · #18 ·
A blocked filter restricts airflow. You know this.

Restricted air flow increases vacuum causing more fuel to be lifted through the jets giving higher fuel consumption.
well this is my first motorcycle, firs restoration, and first motorcycle I ride in my life ( I am 42) ,its a learning process for me. So I will test it wihout air filter (for fuel consumption) and then I will know is it a wrong filter , maybe too dense? also I will check for airflow obstruction under a seat etc
 

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Are you sure the chokes are opening?

If you look from the right side of the bike while working the choke you can see the choke mechanism on the left carb moving.

You can also see whether or not its link to the right carb is turning.

Check the flame screen in the front of the airbox.
 

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I have steal mesh inside airfilter box to stop dirt going into carbs.
That is the flame screen of which CXPHREAK was writing. They can also become partially plugged.
 
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