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43 F won't restart when hot

Posted: Mon Aug 07, 2017 3:47 pm
by Greny
Hi all,

Stripped the carb because wanna prepare the bike for a 5 day Pyrenees ride in September.
Clean the carb out , all went well.
Fired even up from the 1 st Kick !
After a 15 minutes ride , stopped (shut down engine) , 3 minutes later I wanted to restart but couldn't..
Same problem since I have the bike (2 years) , won't start when hot.
I wait 8-10 minutes and then she goes 1st kick...
When shes hot and doesn't wanna start when I kick fuel drips from main float bowl (bottom).
Coil ?

Re: 43 F won't restart when hot

Posted: Mon Aug 07, 2017 6:25 pm
by xtrider
Your running rich on the pilot and needle . These bikes when running rich and you shut off hot get the whole intake flooded with fuel vapors so when you try to restart there isn't enough O² to ignite . If you go a size or 2 leaner on the pilot jet plus drop the needle(or take out the washer) it'll restart much better . I also made an aluminum plate that bolts to the bracket in front of the carbs to separate the engine heat from the carb to reduce temps in the bowl . Also if you have a way to hold the throttle wide open when you walk away from it the vapors have a bigger area to go and get out .

Otherwise before trying to restart , leave the key off and twist the throttle wot then kick the motor over several times to flush the intake . Then start as normal.



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Re: 43 F won't restart when hot

Posted: Mon Aug 07, 2017 7:34 pm
by Greny
Ty xtrider. Could you post a pic of the alu plate ? How can I see which jet is in there ?

Re: 43 F won't restart when hot

Posted: Mon Aug 07, 2017 11:52 pm
by xtrider
Image

You take the bowl off the primary carb and look what # the pilot is . There are limited sizes available . I think most have 46 or 48 pilots. For now maybe turn the fuel mixture screw in 1/2 turn , test , then go another 1/4 turn ,repeat , it'll lean out the lowend some but once it gets to less than 1 turn out it's time to go smaller on the pilot if available. See if it'll clear up good enough before needing to take the bowl off.

The restarting issue is hard on these kickers because they're not being cranked over so fast and steady like the E-starts so they're much more fussy on being run rich . Takes a lot more to flush out the vapors. Even my e-start will sometimes backfire when restarting hot , due to no smaller jet available I have to let it run rich , but it starts so nice cold it's not an issue . I try to park in the wind so it can be cooled off faster and the air takes out the vapors , usually.


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Re: 43 F won't restart when hot

Posted: Tue Aug 08, 2017 7:54 am
by Greny
Ok , ty pic etc.... my 34 l doesn't have that problem. Gonne look into that. Probably gonne run better in the montains , we're going to be all the time around 1600-2200 meters . The restart yesterday was at my place 130 meter altitude :oilleak: :ride:

Re: 43 F won't restart when hot

Posted: Tue Aug 08, 2017 7:37 pm
by Jens Eskildsen
The problem will be even worse at altitude.

See if adjusting the CO-screw/Fuel-screw IN wont cure the problem.

Re: 43 F won't restart when hot

Posted: Wed Aug 09, 2017 12:02 am
by scottieh
I also had problems with my 43f restarting when hot and discovered that my choke was missing the small rubber tip at the end where it goes onto the carb. Once i replaced that with a complete choke my problem went away and i can restart when the bike is hot. :nordie:

Re: 43 F won't restart when hot

Posted: Wed Aug 09, 2017 6:23 pm
by Greny
Jens Eskildsen wrote:The problem will be even worse at altitude.

See if adjusting the CO-screw/Fuel-screw IN wont cure the problem.
Ty tip , the screw your talking about is that the pilot screw ? And turn in or out ?

Re: 43 F won't restart when hot

Posted: Thu Aug 10, 2017 10:39 pm
by scottieh
Greny wrote:
Jens Eskildsen wrote:The problem will be even worse at altitude.

See if adjusting the CO-screw/Fuel-screw IN wont cure the problem.
Ty tip , the screw your talking about is that the pilot screw ? And turn in or out ?
It is the fuel screw that can be adjusted from outside of the carb. Turning it out means more fuel, turning it in means less. At altitude you have less air so less fuel is needed. Turn it in a half turn to start and see how it runs.

Re: 43 F won't restart when hot

Posted: Sun Aug 20, 2017 12:35 am
by xtrider
For some jetting options I see Jets R Us has some I believe are for these carbs ,


http://www.jetsrus.com/a_jets_by_carbur ... ction.html



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