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Discussion Starter · #8 ·
Matt said:
i'm guessing you have a problem with starting the bike and its not starting due to you being a noob and taking the idle screw out?
Bingo! I'm actually posting for my son. Bought bike unregistered about 8 mths ago and hasn't had the money to register it til now. Has been starting it every now and then and it was fine til recently but now when he tries to start it it just tries to kick over for a while and then finally backfires and stops. Has changed the fuel, replaced spark plugs and cleaned the carby but still no luck. I just post the qs as he asks!

A mate suggested the CDI unit was probably the cause but I posted on another site and all the responders said poor fuel was cause and definitely not CDI. (one actually told me to never take advice from that friend again!)

Any advice would be muchly appreciated.
 

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sweet.

theres a few things that you can do.
ensure that all your settings are correct, like the mixture screws. if you are certain, then you can move on.

i normally attach the idle screw such that the plat that it pushes onto is moved up by a few mm. this will give a high idle, which you can adjust once the bike has started.

open up the airbox and spray some start ya bastard down the trumpets. its essentially ether and has saved me much anguish in starting the bike back up after a rebuild. failing that, stick a few drops of fuel down there. if there is anything screwy with the fueling, like leaking carb rubbers (ergh. i had that last week on the vtr. what a pain) it will most likely fail to start. i also have a small funnel which i connect to the fuel pipe, so i know that there is fuel going through, and i can see when it is running down.
also, make sure the vaccum hose is closed. its the small hose that connects to the fuel tap.

get back to me if this doesn't work.
 

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Discussion Starter · #10 ·
Matt said:
sweet.

theres a few things that you can do.
ensure that all your settings are correct, like the mixture screws. if you are certain, then you can move on.

i normally attach the idle screw such that the plat that it pushes onto is moved up by a few mm. this will give a high idle, which you can adjust once the bike has started.

open up the airbox and spray some start ya bastard down the trumpets. its essentially ether and has saved me much anguish in starting the bike back up after a rebuild. failing that, stick a few drops of fuel down there. if there is anything screwy with the fueling, like leaking carb rubbers (ergh. i had that last week on the vtr. what a pain) it will most likely fail to start. i also have a small funnel which i connect to the fuel pipe, so i know that there is fuel going through, and i can see when it is running down.
also, make sure the vaccum hose is closed. its the small hose that connects to the fuel tap.

get back to me if this doesn't work.
I'll pass it on and get back to you ASAP. Many tnx Matt.
 

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Best way to get them to start after a long period of inactivity is something like CRC Aerostart which is basically just ether. All you do is take the tank and airbox lid off, then spray it into the top of the carb bells. If your fuel line isn't long enough to keep the tank connected while you're doing that then one of the handier things you can buy is a long piece of fuel line so you can put the tank on a nearby bench.
 

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*edit: that was weird...
*double edit: stil weird. its taking a "b" to mean break, not bold...
Drew said:
Best way to get them to start after a long period of inactivity is something like CRC Aerostart which is basically just ether. All you do is take the tank and airbox lid off, then spray it into the top of the carb bells. If your fuel line isn't long enough to keep the tank connected while you're doing that then one of the handier things you can buy is a long piece of fuel line so you can put the tank on a nearby bench.

Matt said:
open up the airbox and spray some start ya bastard down the trumpets. its essentially ether and has saved me much anguish in starting the bike back up after a rebuild. failing that, stick a few drops of fuel down there. if there is anything screwy with the fueling, like leaking carb rubbers (ergh. i had that last week on the vtr. what a pain) it will most likely fail to start. i also have a small funnel which i connect to the fuel pipe, so i know that there is fuel going through, and i can see when it is running down.
great minds hey?

eh? what?
 

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Matt said:
*double edit: stil weird. its taking a "b" to mean break, not bold...
It's because you don't have a close tag (]) on your second quote (edit: so the first ] it sees becomes the 'end quote' character).

Newb.

Justin.
 

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I'm assuming you are talking about a CBR250R (MC19)?
My grilfriend has a similar issue after long periods of inactivity, the bike that is not the girl.
Seemed whomever had the bike before did not replace the fuel lines in;
a) Correct order
b) Correct route
c) Correct anything
The fuel lines would pinch and the fuel pump wouldn't prime properly.
Heaps of cranking etc, a few tentative "I want to start" sounds and then run down battery.
I re routed the fuel lines and it is better but me thinks the pump is now border line rooted.
Looking for another to sort the issue.
Any suggestions for a pump anyone?
I have read that it is about 3psi, so really low pressure.
CJ and Angie Mae
 
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