English French German Italian Spanish

Hot starting

Submitted by geoff_mcnulty on Mon, 13/05/2024
Forums
Heavy Twins
Hi my mate has just purchased a 600 dominator and joined the club but is not yet conversant with the procedure to post a problem so ive done it for him. The bike when cold starts first or second kick  and runs ticks over lovely When hot is a mare to get going. if you take it for a ride 1/2 hour leave for 5 mins and try to start it it will not fire. Leave it for 1/2 hour or more it will start again  Any ideas appreciated Regards G  

Submitted by alan_osborn on Mon, 13/05/2024

Permalink

Check you haven't lost the spark? is the coil Hot? Is the carbon brush in the dizzy cap stuck? Is the air hole in the petrol cap blocked?

Submitted by simon_clark on Mon, 13/05/2024

Permalink

As Al says check the spark. Very common problem with an old magneto.  Easy cold start and fine when engine running.  However once engine stopped there is no chance of starting again until everything has cooled down.  The capacitor inside the magneto is the problem.  Rebuild magneto [Paul Wolf] or electronic ignition [preferred].

Submitted by michael_ball on Tue, 14/05/2024

Permalink

Does sound like possible bad condenser, but some bikes need a press on the carburettor tickler for starting under the circumstances you describe.

Submitted by alan_osborn on Tue, 14/05/2024

Permalink

OH yea? How is it there is the cry of EI every time a mag misbehaves? The cost of EI can be as much as the cost of a mag rebuild-£400. With EI you need to fit an ignition switch, you are now totally reliant on a decent battery and battery charging. Conversion to 12V is preferred. Is the dynamo up to it? An alternator will have sufficient power.

Submitted by david_cooper on Tue, 14/05/2024

Permalink

I replaced my Concentrics with the correct Monoblocs.  When hot, I now need to give it a lot of throttle opening...which Amals don't usually want on starting.  (I must sort out the pilot screw.  But drawback with monoblocs is poor access) it starts starts normally when cold

Submitted by robert_tuck on Tue, 14/05/2024

Permalink

Irregular usage makes it difficult to get the tuning just right. I have  given the pilot screw a half turn (in or out) and used the bike for a few runs and checked the plug condition . Even a quarter turn out of the pilot screw can clean up the plug . and the bike will go from a reluctant warm starter to a first kick   warm starter with just a quarter turn outwards (anti clock) . Summer and winter require a slightly different setting. A new carb makes a huge difference to the reliability of the idle .

Submitted by geoff_mcnulty on Fri, 26/07/2024

Permalink

Hi guys Hot starting on my mates 99. Over the last few months we have changed the pick ups and put electronic ignition in the mag but still if you get the bike hot say for  10 15 miles it will not start even flooding the carb to excess. It has to be left at least 30 mins when it seems to have cooled down before it will start again Any idears on what it could be as its getting pretty desparardo now and expensive  If the fuel is boiling before it reaches the cylinders what can be done to start it. Regards Geoff 

Submitted by barry_carson1 on Fri, 26/07/2024

Permalink

hello, is the choke working ok.  just a thought i had similar symptoms with a thorspark ign and dynamo setup. the bike would charge ok when engine was warming up. until it got up to normal temp. put the lights on then the charge would slowly drop off. then the bike would come to a stand still, with a semi flat battery. i later found it to be the what i will call the drive clutch to the dynamo, was slipping when hot. mind you i assume yours to be alternator setup.  barry

 


Norton Owners Club Website by 2Toucans