Author Topic: timing camshaft when reassembling  (Read 726 times)

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Offline Johan Moller

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timing camshaft when reassembling
« on: March 08, 2016, 06:18:26 AM »
Hi. I am a new member and I am thinking about timing of the camshaft. I took the camshaft out at TDC 1-4 and the notch pointing at 12 o´clock - all according to the manuals - and then took off the the cylinder head. After that I have rotated the crankshaft a couple of times and I am not sure it is in the original position.  I haven´t touched anything on the right (timing) side of the bike. The manual only says that when reinstalling the camshaft , do so at TDC 1-4 and put the notch att 12 o´clock. That´s no problem but since there are 2 occasion on the full stroke cycle (2 revolutions of the crankshaft) in which the TDC 1-4 appears, how can I know in which revolution I should put the camshaft back with the notch at 12 o´clock?  I can´t get it out of my head that the signal to fire the cylinders could get 180 degrees wrong.

This might be an amateurs - wich I am  :) - question but still.

Offline Johan Moller

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Re: timing camshaft when reassembling
« Reply #1 on: March 08, 2016, 11:16:00 AM »
I forgot to say that I have a 750 K2.

Offline mystic_1

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Re: timing camshaft when reassembling
« Reply #2 on: March 08, 2016, 12:04:41 PM »
No worries, this is a question that comes up a lot. The 750 uses a wasted spark ignition, meaning that it fires at the top of the compression stroke and also at the top of the exhaust stroke. So, it really is impossible to get this wrong.

mystic_1
"A ship in harbor is safe, but that is not what ships are built for."
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My build thread:  http://forums.sohc4.net/index.php?topic=68952.0

Offline Johan Moller

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Re: timing camshaft when reassembling
« Reply #3 on: March 08, 2016, 11:02:22 PM »
That´s excellent. Thanks for your reply. Puts my mind to rest.