Starting problems & Race bike

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paulwolf
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Starting problems & Race bike

Post by paulwolf » Sat Jul 12, 2014 3:47 pm

Hi,My Commander has developed a problem when starting from cold,with the choke on,turn the key and it starts on the right hand cylinder,then after about 30 to 40 secs the left cylinder fires up,Its ok when the engine is hot and runs ok,i have fitted 2 new plugs but it`s still the same.Anyone know what the problem is?.Also i am on the committee of the Bristol branch of the NOC and help to organise the Bristol Bike Show at Shepton Mallet each year and for the last 2 years have won 1st club stand.For the 2015 show in Febuary we are doing a show on Rotary`s and we have most of the models apart from a genuine race bike,does anyone know someone who has one and would like to display it at the show and is there such a thing as a cut away rotary engine about that we could display.If anyone can help please phone me on 07831446958.Thanks Paul Wolf

paulwolf
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Re: Starting problems & Race bike

Post by paulwolf » Sun Jul 13, 2014 12:01 pm

paulwolf wrote:Hi,My Commander has developed a problem when starting from cold,with the choke on,turn the key and it starts on the right hand cylinder,then after about 30 to 40 secs the left cylinder fires up,Its ok when the engine is hot and runs ok,i have fitted 2 new plugs but it`s still the same.Anyone know what the problem is?.Also i am on the committee of the Bristol branch of the NOC and help to organise the Bristol Bike Show at Shepton Mallet each year and for the last 2 years have won 1st club stand.For the 2015 show in Febuary we are doing a show on Rotary`s and we have most of the models apart from a genuine race bike,does anyone know someone who has one and would like to display it at the show and is there such a thing as a cut away rotary engine about that we could display.If anyone can help please phone me on 07831446958.Thanks Paul Wolf
I forgot to say that the rev counter don`t work untill the left cylinder fires up.

Ian
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Re: Starting problems & Race bike

Post by Ian » Sun Jul 13, 2014 7:51 pm

Mine has done this since I bought it in 1995!I reckon it's because the frame drain cheerfully allows oil to run down to foul the plug. I believe some have fitted a diverter in the form of a bottle to catch draining oil but still connecting the air side to the inlet manifold. I have not done this but always mean to. I'm sure Mr Negus of this parish knows all about this. It's worse if the bike is parked on the prop stand.The reason the rev ounter doesn't work is because it is triggered from the left coil so it won't work until there are sparks.

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Richard Negus
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Re: Starting problems & Race bike

Post by Richard Negus » Sun Jul 13, 2014 10:59 pm

Ian wrote:The reason the rev ounter doesn't work is because it is triggered from the left coil so it won't work until there are sparks.
To be more specific, it's triggered by a feed from the 'ground, low-voltage, side of the coil. Thus, tacho doesn't work = no signal to that coil, and is an almost certain indication of an ignition unit fault, or an intermittent fault in the wires/connectors between the ignition unit and that coil.Often, it's the other way round when the tacho works with a cold engine and then, when the ignition unit is hot, the engine runs on one and the tacho stops.I'd look at all the joints/connections on the black/yellow (or black/white - can never remember which) for a corroded wire.
Slower slower, no faster faster - the joys of old fogey mode to hooligan mode at the flick of a switch

paulwolf
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Re: Starting problems & Race bike

Post by paulwolf » Mon Jul 14, 2014 6:15 pm

It all started when the tick over was all over the place and i noticed the left side was sucking in air in the nipple behind the air filter so i blocked that off with a piece of tube,( did i do the correct thing or is the nipple connected somewere with a piece of tube)then the bike ticked over ok.now i will check the wires & conecters.Thanks for all your help.Paul

paulwolf
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Re: Starting problems & Race bike

Post by paulwolf » Thu Jul 31, 2014 9:06 am

Richard Negus wrote:
Ian wrote:The reason the rev ounter doesn't work is because it is triggered from the left coil so it won't work until there are sparks.
To be more specific, it's triggered by a feed from the 'ground, low-voltage, side of the coil. Thus, tacho doesn't work = no signal to that coil, and is an almost certain indication of an ignition unit fault, or an intermittent fault in the wires/connectors between the ignition unit and that coil.Often, it's the other way round when the tacho works with a cold engine and then, when the ignition unit is hot, the engine runs on one and the tacho stops.I'd look at all the joints/connections on the black/yellow (or black/white - can never remember which) for a corroded wire.
I cleaned the contacts in the 2 plugs coming from the ign box and the bike now starts on both cylinders.Thanks for your help.Paul

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