Author Topic: smoking  (Read 1125 times)

Offline Frenchy

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smoking
« on: 02.06. 2010 14:15 »
I'm trying to figure this A7 out.  I tried it 5/16th below TDC, but I think I have it set a little off.  When I kick it over it fires but doesn't wanna run.  Also, it shoots some fire back thru the carb.  That means it's early, right?  That the intake valve isn't quite closed when it fires?  It's also spitting some smoke out the right muffler.  The smoke looked white to me, but I'm not totally sure.  Could that be a byproduct of not being timed right?
1957 A7 bobber, swing arm
Columbus, Ohio, US

Offline muskrat

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Re: smoking
« Reply #1 on: 02.06. 2010 14:33 »
G'day Frenchy,
                        Below TDC ! I hope you mean Before TDC. 5/16" is right, you could try a little (1/32") later. Also check that it is timed the same on both cylinders and the valve clearances are ok.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline dpaddock

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Re: smoking
« Reply #2 on: 02.06. 2010 15:45 »
Is the timing actually 5/16"? With the advance unit fully set? On the proper cylinder? Does it run at all?

David
David
'57 Spitfire


Offline Frenchy

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Re: smoking
« Reply #3 on: 02.06. 2010 18:44 »
Before TDC...  That's what I meant.  I was still a bit foggy this morning when I wrote that.   

Do you set the valve clearance warm or cold?  I haven't gotten it to run yet.  It fires and acts like it wants to but just never catches.  Also, I only looked at the one piston when setting the timing.  I'll look at both.  Does it matter which one you set the timing on?
1957 A7 bobber, swing arm
Columbus, Ohio, US

Offline chaterlea25

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Re: smoking
« Reply #4 on: 02.06. 2010 22:08 »
Hi Frenchy
Make sure the plug leads are the right way round!!!
have you tried swapping them round??
HTH
John O R
1961 Super Rocket
1963 RGS (ongoing)

Offline muskrat

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Re: smoking
« Reply #5 on: 02.06. 2010 22:15 »
G'day Frenchy,
                          set valves cold.
  As David said, make sure the auto advance is wedged to the full advance position. It's been about 13 years since I played with a magy but I remember I made wooden wedges, one to hold the AAunit and the other to hold the points plate still. The most accurate way to time is with a degree disc behind the cush drive nut and a pointer from one of the case screws. Use a cig paper to find where the points just start to open and mark the disc. turn the motor 1 turn and check again. Both should be the same ( a couple of degrees out is ok, 5 or more is not). It's all a bit fiddly, while the disc is in place find TDC and mark it. now mark 34 degrees before, that's your full advance mark.
 Gee I luv my Boyer!!
Cheers
PS. Just saw John's post. Try that first.
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7