SQ4 Misfire

Singles, twins and fours.
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simon.holyfield
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Re: SQ4 Misfire

Postby simon.holyfield » Mon Oct 22, 2018 6:35 am

Thanks Mark - as always it's great that you can cross - check my set up! I'll stop worrying about charging for the moment.

I think I have a very nice idle now, and a bike that starts very easily after sorting the HT oil contamination, re-sealing the rocker boxes and resetting the timing & valve clearances:

https://ariel-square-four.blogspot.com/ ... rvice.html

I don't know if any of you can add anything to this 'how to do it' post?

https://ariel-square-four.blogspot.com/ ... -nine.html
cheers

Simes

'51 Square Four,
'58 Huntmaster,
'42 W/NG,
'30 Model A
http://ariel-square-four.blogspot.com

MARK.WALSH
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Re: SQ4 Misfire

Postby MARK.WALSH » Mon Oct 22, 2018 8:51 pm

Simes
the bike sounds great on the video - slightly better / even tick-over than mine and mechanically quieter (also my exhaust pipes are a bit more raucous )
Was it fairly cold when you let it idle?

Hopefully your mis-fire has gone, but now I have heard how mechanically quiet your bike is I might look under the rocker covers armed with your advice on cam positioning for setting tappets. (I haven't touched them for over 2000 miles)
If I can I might try and get a video of mine on tick over during the weekend and upload it.

I'll have a think on the 'how to do it post', although I cant think of many things you haven't covered. Maybe how to hang on to the bike at 70mph as it weaves down the road could be a good one :0
Seriously though - with cooler days these bikes run better, and my bike is flying along without a problem around the country lanes and 'A' roads of Kent - apart from the leaks!
Hmm, maybe an article on better engine breathing

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simon.holyfield
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Re: SQ4 Misfire

Postby simon.holyfield » Tue Nov 06, 2018 9:49 am

Well, I know the temperature in the UK has dropped a bit but I have completed a few test runs and can report that the misfire has not yet returned.

It might be a bit premature but I'm hopeful...
cheers

Simes

'51 Square Four,
'58 Huntmaster,
'42 W/NG,
'30 Model A
http://ariel-square-four.blogspot.com

keith wainwright
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Re: SQ4 Misfire

Postby keith wainwright » Sat Nov 10, 2018 2:07 pm

Make sure that battery is producing 6volts +. Anything under 6 volts on a Coil Square Four will cause problems with misfiring bad starting. I fit the sealed gel type 11amp hour battery but you must not let them become discharged. I use a tricle charger with the leads permanently connected to the battery. Connecting to charger via small plug a socket. Hope the above helps Keith

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dave.owen
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Re: SQ4 Misfire

Postby dave.owen » Sat Nov 10, 2018 2:49 pm

I've fitted an led volt meter to the top of my battery box on the Sq, can see instantly what voltage is being generated.
Dave
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simon.holyfield
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Re: SQ4 Misfire

Postby simon.holyfield » Sat Nov 10, 2018 2:56 pm

I'm running two VRLA batteries in parallel, one 8 Ah, one 12 Ah. The open circuit voltage is 6.2; at idle I see 6.8.

I'm thinking about a voltmeter...
cheers

Simes

'51 Square Four,
'58 Huntmaster,
'42 W/NG,
'30 Model A
http://ariel-square-four.blogspot.com


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