HHB Complete CDI system ignition timing

nghieplk

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My 80 xs is running good. After installing the shell cam from Hoosracing and replace the new piston set. One day it start with "woofing" sound, cannot run. I've check the carb, they are new and good. I thought because of the bad coil. After trying many times, i decided to get the new HHB full Cdi system. When the electrician install it, he told me the ignition timing on my xs not correct as Hugh manual marked at TDC. So i wonder if we should check something relate to the engine before setting the timing?
Thank you for help!

The engine sound:
 

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You need to verify true TDC via piston position. Trusting any marking on that aftermarket rotor is a very bad idea.
1: Verify true TDC, and mark rotor and stator accordingly, with a Tippex or similar.
2: Compare true TDC with any TDC marks on the HHB rotor/stator. If they agree, that is good.
3: Use a tape measure around the rotor. Divide circumference in mm with 360. That will give mm per degree.
4: Decide your desired max ignition advance, for example 38 or 39 degrees.
5: Make your own "full advance" mark based on step 3 and 4
6: Run engine, use a strobe lamp to check/ verify actual advance.
7: Take necessary steps to correct timing, if neccessary
 
I am also about to install a HHB CDI kit. His instructions state when at TDC the keyway or woodruff key on the crank will be facing up which from pics and what I am assuming is at 12 o'clock on the crank.

When I am at TDC my woodruff key is at 6 o'clock, bottom of the crank...is this a rephased crank possibly? With the OEM charging components in place my TDC marks all line up perfectly still with the marks on the case so I am a bit confused.

In one picture in his manual you can see the keyway on top of the crank but then further on in where he makes yellow paint pen marks it appears to be at 6 o'clock...

First pic shows keyway at top, second pics show new yellow marks for timing....Thoughts?

EDIT: Motor is not rephased as both pistons move up/down together...still learning here :)
 

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When the pistons are at TDC the little pin on the RH camshaft is in the 12:00 position. I`ve used the HHB CDI and it`s foolproof.:thumbsup:
 
I am also about to install a HHB CDI kit. His instructions state when at TDC the keyway or woodruff key on the crank will be facing up which from pics and what I am assuming is at 12 o'clock on the crank.

When I am at TDC my woodruff key is at 6 o'clock, bottom of the crank...is this a rephased crank possibly? With the OEM charging components in place my TDC marks all line up perfectly still with the marks on the case so I am a bit confused.

In one picture in his manual you can see the keyway on top of the crank but then further on in where he makes yellow paint pen marks it appears to be at 6 o'clock...

First pic shows keyway at top, second pics show new yellow marks for timing....Thoughts?

EDIT: Motor is not rephased as both pistons move up/down together...still learning here :)
The woodruff key for the rotor is at 6:00 with the pistons at TDC. That's normal.



1674594431387.png
 
@Jim, ok sweet deal. His instructions seem to have state otherwise... My motor is 100% not rephased..

@halfmile thanks mate yes, that is good to go. Im at TDC on the LH cylinder so my original little dowel pin is at 6 o'clock. I was worried about the crankshaft setup but seems all is good.
 
To use correct terms and be on same page: the dowel pin (@ halfmile refers) is on right of camshaft and positioned @ 12 O'clock, the keyway (woodruff key @ Jim refers) on left crankshaft, positioned @ 6 O'Clock - all at TDC on compression on left cylinder. All that to verify motor is at correct position to install and time ignition per HHB instructions.:)
 
To use correct terms and be on same page: the dowel pin (@ halfmile refers) is on right of camshaft and positioned @ 12 O'clock, the keyway (woodruff key @ Jim refers) on left crankshaft, positioned @ 6 O'Clock - all at TDC on compression on left cylinder. All that to verify motor is at correct position to install and time ignition per HHB instructions.:)
I’m on TDC compression stroke on the LH cylinder and my camshaft dowel pin is at 6 o’clock.
 
You're TDC Exhaust stroke, if ya roll the crank one revolution CCW, the cam dowel pin will be @ 12 O'clock and align with the HHB instructions
 
You're TDC Exhaust stroke, if ya roll the crank one revolution CCW, the cam dowel pin will be @ 12 O'clock and align with the HHB instructions
Ok..I had my finger over the spark plug hole and felt pressure and got a big hiss of air as I removed my thumb and returned back to the T mark which I thought was the compression stroke
 
Looks like this fella thought similar as me..
https://www.xs650.com/threads/cam-problem.45669/

I had the camshaft dimple lined up to the head and and every else lined up when I put the cam chain on. Triple checked tdc and timing before I put the rest of the head together. Was easily able to set valve clearances too.

I unfortunately tend to over think mechanical things at times till where I get confused or second guess what I did and then the forum asking comes up lol so thank you all for the advice and help!

Is it possible the cam on an XS could be 180 out?
 
I had the camshaft dimple lined up to the head and and every else lined up when I put the cam chain on.
Pics from the Tech Section....
This is the left side. Notch should point straight up.


1674607636613.png



On the right side of the head you'll see the dimple flush with the aft face of the head.


1674607702608.png



That how yours looked?
 
Ok here’s the deal. Pics to show.

Left cylinder valves loose with clearance at TDC but my camshaft pin is facing 6 o’clock. Finger over spark plug hole when turning over I get pressure at this point when getting close to TDC. This is the compression stroke, yes?

Right side valves tight.

Is this not normal? Does it matter which way the dowel pin is facing at a certain location?
 

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When the pistons are at TDC the little pin on the RH camshaft is in the 12:00 position. I`ve used the HHB CDI and it`s foolproof.:thumbsup:
Is this for the right or left cylinder? When my pin on the camshaft is in the 12 position my RH valves have clearances, LH side is tight..
 
Is that last pic of the right cam cover or left cam cover?

Procedure for determining TDC compression is rotate motor until intake valve opens, then closes...then next TDC is TDC compression...
 
Is that last pic of the right cam cover or left cam cover?

Procedure for determining TDC compression is rotate motor until intake valve opens, then closes...then next TDC is TDC compression...
It is for the right cam cover...I did that to determine TDC on compression stroke.

Rotated the engine until I saw the LH intake valve open then close and then continued to my T mark for TDC...valves currently on this side have play. Right side is tight.
 
Here are pics from HHB cdi install. His RH cam shaft cover doesnt appear to show the dowel pin hole which leads me to believe it is on the bottom, same as his crankshaft key is.
 

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Here’s another pic of my advance back on the camshaft for reference. The two hash marks line up as you can see. This is for TDC LH side compression stroke
 

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