Rapide backfires when starting

Mark Fisher

Well Known and Active Forum User
Non-VOC Member
I think that choke and tickler is overkill unless it is a very cold day. Since I also use a grossset starter Danno could try doing it the way I do on my shadow ie: apply full choke on both cylinders, press starter button with throttle closed and bike should fire right up....too simple? There is of course one important differece between my shadow and danno's bike...I have a BTH and he has lucas rita. Both systems will produce a good sprk at low RPM BUT the lucas rita relies on the battery and needs a decent voltage to work properly so using the starter may be affecting the ignition system. My mark 3 commando has this issue if the battery is a bit low (usually when the bike has not been used for a bit)... the starter will turn the engine over but it doesn't fire up, kick it and it starts right up. food for thought.
 

danno

Well Known and Active Forum User
Non-VOC Member
Thanks for the help. I'll try less fuel.
Getting the cylinders in the correct position
is a bit trial and error. Probably got something
to do with having to kick it over too much.
 

A-BCD

Well Known and Active Forum User
Non-VOC Member
My late father worked permanent nightwork, but he used to come home for supper between 9 and 10 pm He would leave home at 9:50 every night. He would kick over his C Rapide twice, it would backfire, then start on the 3rd kick without fail. Our neighbours would set their clocks every night at 10 to 10 !!
 

danno

Well Known and Active Forum User
Non-VOC Member
I think that choke and tickler is overkill unless it is a very cold day. Since I also use a grossset starter Danno could try doing it the way I do on my shadow ie: apply full choke on both cylinders, press starter button with throttle closed and bike should fire right up....too simple? There is of course one important differece between my shadow and danno's bike...I have a BTH and he has lucas rita. Both systems will produce a good sprk at low RPM BUT the lucas rita relies on the battery and needs a decent voltage to work properly so using the starter may be affecting the ignition system. My mark 3 commando has this issue if the battery is a bit low (usually when the bike has not been used for a bit)... the starter will turn the engine over but it doesn't fire up, kick it and it starts right up. food for thought.

Thanks
Having better luck now with kickstarting with no explosions.
Holding down tickler for 3 secs works and also making sure the engine's on the right stroke.
Also find opening throttle helps.
Doesn't start so well on the starter though, maybe due to the Lucus needing a decent voltage like you say.
 

Howard

Well Known and Active Forum User
VOC Member
Thanks
Having better luck now with kickstarting with no explosions.
Holding down tickler for 3 secs works and also making sure the engine's on the right stroke.
Also find opening throttle helps.
Doesn't start so well on the starter though, maybe due to the Lucus needing a decent voltage like you say.

Keep at it Danno. Like the rest of us you'll find the best technique to suit yourself and your Vin.

I'm not sure about Vin starters (never had one) but I'd think you could use jump leads from a car battery to check if it's a voltage/battery problem - I'm sure someone will scream "Don't do it!" if I'm wrong. (I assume you're on 12 volt)

H

If that works, try cleaning and tightening all the connections, battery, earth(s), solenoid (?), starter motor - if they're dirty or corroded you could lose enough volts to cause problems.

H
 
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clevtrev

Well Known and Active Forum User
VOC Member
Thanks
Having better luck now with kickstarting with no explosions.
Holding down tickler for 3 secs works and also making sure the engine's on the right stroke.
Also find opening throttle helps.
Doesn't start so well on the starter though, maybe due to the Lucus needing a decent voltage like you say.
I`m really surprised you haven`t stuffed the starter yet. Never use the starter with motor in place, until you have sorted the engine properly.
 

vincentbarmy1

Forum User
Non-VOC Member
Some electronic ignitions will give a spark when the ignition is switched on (both cylinders on a twin), so if there is a fuel mixture in the cylinder it will fire it. One of the DISadvantages of electronics!
Mike
 

Bazlerker

Well Known and Active Forum User
Non-VOC Member
I think the real problem is a lack of VOC membership documents in the tool tray under the seat. Join us, and the backfiring will disappear as if by magic!
 
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