The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => A7 1946-1950 => Topic started by: Drew Back on 19.10. 2016 01:57

Title: Motor just stops
Post by: Drew Back on 19.10. 2016 01:57
Well I got the bike running real nice but on the last ride it just died and would not kick over kick arm locked up kicked smooth with clutch pulled in..Put in gear and rocked it back and forth a few times and started right back up like something bound up any ideas where to start looking?? Primary chain was good and not binding did put a thicker cork washer on breather valve could it be something inside tranny??
Title: Re: Motor just stops
Post by: muskrat on 19.10. 2016 07:26
G'day DB.
My 1st thought is she had a partial seizure. I have had that happen with a new tight motor on a hot day. One minute later she is free and started.
Get your hands on an endoscope camera and have a look down the plug holes for any scoring of the bores.
Cheers
Title: Re: Motor just stops
Post by: Klaus on 19.10. 2016 09:05
I agree with muskart, having this on an engine more than 5 times. The engine is going harder so I pull the cluth and motor emediately stopped, rolling a few meters release the cluthlever and its like nothing happend. This phenomen appered only on hills or hard work to the engine against heavy winds, going full throttle about one to two miles. I sort out this was a lean combustion and give her a bigger main jet.  This seizures was allways  light ones, so I doesn't care about and do a trip to Ireland with over 4000km. A few weeks later at home there was a pinking only on ascceleration. I had no idea what this will mean, as I give full throttle after a roundabout the sparkpluck get off the thread. So I had to put off the head and one piston showed a crack from one  end of the wrist pin to the other. Now this pistons are in the show case with other offers to the god of speed *whistle*

cheers Klaus
Title: Re: Motor just stops
Post by: KiwiGF on 19.10. 2016 10:54
At the risk of pointing out the obvious drew, are you familiar with the fact that the kickstart gears often do lock up and hence one pulls the clutch in to ensure they are engaged properly before kicking the engine over? You probably know this but just thought I'd ask.......
Title: Re: Motor just stops
Post by: Drew Back on 19.10. 2016 13:46
Thank you for the input the engine was not even hot when this happened..The first time was in driveway after running for about a minute shut it off it sat for about 10 minutes then could not kick it over the second time was about a one mile ride then it just stopped did not think to pull in clutch before it stopped. It is running nice and smooth no loud noise or knocking..I will try to pick up a bore scope this weekend to see what is going on inside cylinders it does kick over nice and smooth..