Author Topic: Cam chain timing question  (Read 1543 times)

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Offline 88BuckMeister

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Cam chain timing question
« on: January 30, 2024, 06:10:59 PM »
How much difference will moving the gear sprocket one tooth in either direction make? I ask because I want to make darn sure I got the tuning right. Im attaching picks (its a 650 cam but ive read or heard nothing about it being timed differently).

Does the T mark behind the points line up just once or twice? (Like could I have it 180 degrees backwards from the compression stroke...)

I put the TDC mark lined up with the case perfectly. I then lined up the gap in the cam with the head as stated in the manual. It seemed a little off, so then I backed the sprocket off one tooth, realigned the bolt holes and it was pretty much level. I guess I'm asking...

1- does the T mark line up once, or twice (one for each ignition and exhaust) and does that make a difference? The manual just says line it up and that's it

2- if I was off a tooth in either direction on the cam gear, would it look like oh no way that's lined up (a big difference?) or would it be just a little faintly in one direction or the other as to make me think it's proper but it really isn't? The manual makes it sound dummy proof

Offline Mark1976

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Re: Cam chain timing question
« Reply #1 on: January 30, 2024, 07:18:34 PM »
The manual shows it from the ignition side, so like it says. 1&4 TDC, go straight up to the camshaft #4 cyl, cam slot aligned with the head surface, cam slot facing to the front of the engine. On cyl #4 the lobes are up at like 2 and 10 oclock.
In your pic, somethings not right. The notch is right but the lobes are down?
The 3rd pic is from the #1 cylinder perspective, is that correct.
« Last Edit: January 30, 2024, 07:29:26 PM by Mark1976 »
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #2 on: January 30, 2024, 07:27:49 PM »
The manual shows it from the ignition side, so like it says. 1&4 TDC, go straight up to the camshaft #4 cyl, cam slot aligned with the head surface, cam slot facing to the front of the engine. On cyl #4 the lobes are up at like 2 and 10 oclock.
In your pic, somethings not right. The notch is right but the lobes are down?

I noticed that as well, but if you hold the 550 cam and 650 cam next to each other, the lobes are exactly ehe same orientation, and the notch is in the same place. So with the notch facing forward and level with the head, the #4 lobes do point downward regardless of whether it's the 550 cam or the 650 cam which appears to be opposite of what the manual showed. Maybe it's just an example because with any can lined up those lobes point downward at like 4 and 8...I believe all pics are from the right side of the engine
« Last Edit: January 30, 2024, 07:33:24 PM by 88BuckMeister »

Offline Mark1976

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Re: Cam chain timing question
« Reply #3 on: January 30, 2024, 07:31:14 PM »
The orientation from the number 1 cylinder is correct. Lobes down.  The manual does fron #4, lobes up, that's where where we're off.
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #4 on: January 30, 2024, 07:35:15 PM »
The orientation from the number 1 cylinder is correct. Lobes down.  The manual does fron #4, lobes up, that's where where we're off.

Yeah all of my pics are from the right side of the engine. But only one side of the cam has the notch so it can never be from the #1 perspective for timing purposes. I'm not sure why the manual shows the #4 lobes pointed upward, but on both the 550 and 650 cam, lining that notch up to the forward position always points the lobes down...I really can't mess this up it will be catastrophic with the massive lift of this cam

Offline Mark1976

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Re: Cam chain timing question
« Reply #5 on: January 30, 2024, 07:38:40 PM »
Thats mine installed. 
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #6 on: January 30, 2024, 07:39:46 PM »
You can see from the manual the slot in the cam should face forward, but they don't day that specifically. It's just implied. But they're also showing the #4 lobes pointed upward, which can't happen without facing the notch backward...

Offline Mark1976

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Re: Cam chain timing question
« Reply #7 on: January 30, 2024, 07:40:12 PM »
That doesn't show proper orientation..
Ok, stop.
Everything is done from the ignition side of the engine.
« Last Edit: January 30, 2024, 07:42:42 PM by Mark1976 »
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #8 on: January 30, 2024, 07:41:32 PM »
Uh oh what did I do wrong...it shows the notch forward facing the front of the bike from the right side perspective...

Offline Mark1976

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Re: Cam chain timing question
« Reply #9 on: January 30, 2024, 07:43:04 PM »
Uh oh what did I do wrong...it shows the notch forward facing the front of the bike from the right side perspective...
Yes...
Your 180 out.
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Offline scottly

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Re: Cam chain timing question
« Reply #10 on: January 30, 2024, 07:48:25 PM »

Does the T mark behind the points line up just once or twice? (Like could I have it 180 degrees backwards from the compression stroke...)


1- does the T mark line up once, or twice (one for each ignition and exhaust) and does that make a difference? The manual just says line it up and that's it


The T mark lines up once per crankshaft rotation of 360 degrees, while the cam only rotates 180 degrees. The cam can't be 180 degrees out; if it looks wrong, turn the crank a full 360 degrees and check again. ;)
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #11 on: January 30, 2024, 07:48:51 PM »
So you're saying with the timing mark on T, the notch in the camshaft should be facing 9 o'clock and not 3 o'clock?

Offline scottly

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Re: Cam chain timing question
« Reply #12 on: January 30, 2024, 07:49:49 PM »
Uh oh what did I do wrong...it shows the notch forward facing the front of the bike from the right side perspective...
Yes...
Your 180 out.
::)
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #13 on: January 30, 2024, 07:50:56 PM »
I followed the manual and with the t mark lined up I put the cam notch at 3 o'clock level with the cylinder head. The only issue is that the lobes face downward when the pic shows them facing upward. There's no physical way to install it with the #4 lobes facing upward without the notch being at 9 o'clock.

Is it that I'm at top dead center on #s 2&3?

Offline Mark1976

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Re: Cam chain timing question
« Reply #14 on: January 30, 2024, 07:58:27 PM »
TDC 1&4, align everything from the #4 cyl. Notch facing forward, 
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #15 on: January 30, 2024, 08:03:42 PM »
TDC 1&4, align everything from the #4 cyl. Notch facing forward,

But that's what I did...TDC # 1&4, TC mark lined up with the case index, notch facing forward. And my lobes are facing downward. Is the manual pic just misleading?

Offline Mark1976

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Re: Cam chain timing question
« Reply #16 on: January 30, 2024, 08:06:26 PM »
Post a pic, ignition side. Just like the manual.
the 3rd pic is correct.
My mistake...it looked as if I was seeing it as #1.
« Last Edit: January 30, 2024, 08:11:34 PM by Mark1976 »
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Offline Mark1976

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Re: Cam chain timing question
« Reply #17 on: January 30, 2024, 08:14:43 PM »
TDC 1&4, align everything from the #4 cyl. Notch facing forward,

But that's what I did...TDC # 1&4, TC mark lined up with the case index, notch facing forward. And my lobes are facing downward. Is the manual pic just misleading?
That's how I interpreted as well.
Notch forward,  lobes down,  pulled out a cam.
As Scott mentioned above, once its in, turn the crank 2 full revolutions, it will align right back up where you started.
« Last Edit: January 30, 2024, 08:34:46 PM by Mark1976 »
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Offline Tracksnblades1

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Re: Cam chain timing question
« Reply #18 on: January 30, 2024, 08:21:43 PM »
In reference to your question of how much does 1 tooth of the camshaft sprocket move the camshaft.
With a 34 tooth camshaft sprocket, each tooth should move the camshaft 10.58xx actual degrees or 21.16 crankshaft degrees.
.
Each sprocket tooth of the crankshaft’s sprocket will halve it..

Once you get your camshaft timing figured out, a protractor sat at the end of the camshaft could give you a quick visual reference of what 10.58 or half that looks like..🤔

With a new or worn out cam chain, I believe a one cam sprocket tooth off either advanced or retarded will negatively affect the performance.

« Last Edit: January 30, 2024, 10:59:38 PM by Tracksnblades1 »
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Offline dave500

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Re: Cam chain timing question
« Reply #19 on: January 30, 2024, 11:25:20 PM »
put the ignition pointer at 1/4 T,then install the cam notch front or rear,wont matter,9 or 3 oclock,watch out for daylight saving though.
that cartoon sketch is some what generic aswell,dont take too much notice of the actual lobes in that.
« Last Edit: January 30, 2024, 11:31:56 PM by dave500 »

Offline bryanj

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Re: Cam chain timing question
« Reply #20 on: January 30, 2024, 11:28:10 PM »
It dont matter a stuff if it points forwards or backwards, if you rotate the crank one turn till the T lines up again it goes from 3 to 9 or vice versa
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Offline Tracksnblades1

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Re: Cam chain timing question
« Reply #21 on: January 31, 2024, 12:49:46 AM »
It dont matter a stuff if it points forwards or backwards, if you rotate the crank one turn till the T lines up again it goes from 3 to 9 or vice versa

The crank triggered wasted spark advantage…😁
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Offline dave500

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Re: Cam chain timing question
« Reply #22 on: January 31, 2024, 01:00:37 AM »
nothing to do with ignition,its the same for any single cam engine,the cam cant be 180 out.

Offline Tracksnblades1

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Re: Cam chain timing question
« Reply #23 on: January 31, 2024, 02:10:43 AM »
Read the posts again……Dave…🙄

Nary once did I say the camshaft was 180* out…or could be….🙄🙄

The crank triggered distributor-less advantage I was referring to was the fact the camshaft’s timing right or wrong  doesn’t affect the proper ignition timing either…nor can it ever be 180* out of timing with the crankshaft with it being pinned to the crankshaft, other than improper wiring…🤔
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Offline 88BuckMeister

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Re: Cam chain timing question
« Reply #24 on: January 31, 2024, 06:13:17 AM »
You guys rock. Still trying to.fogure this out, but I understand what you all are saying. I laid in bed thinking about it until like 1 am. I get it with the 180 rotation relative to the crank, and in mind the only way it could be 180 out of in relation to ignition (2 full revolutions per cycle, meaning 180 out would mean ignition is occurring at the exhaust stroke instead of the compression stroke) but since I don't yet fully understand the ignition system on the bike, I'll take your word for it that that can't happen on this bike. I'll take into account all your advise and pull the head off and see what I've got! Thank you all so much