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Discussion Starter #1
Alright, seriously I'm stumped. I had my timing dead nuts on before I went riding last week. Since then I've adjusted the valves and cam chain tension. Now my timing is WAAAAY off. I can get the points to close and spark, just not where they're supposed to. Again, I did the timing a week ago, so I don't think I burned my points that far down from one ride...

It's almost like when I adjusted the cam chain tension I slipped a tooth or two somewhere. It looks to me like I'm a few degrees off on the actual allignment between the rotor and cam. Not really sure what to do from here, but can't get it back in time. New points? Re-align cam?

Do these points look that bad? (big pic for detail)



WTF...
-MK
 

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mktsc said:
Alright, seriously I'm stumped. I had my timing dead nuts on before I went riding last week. Since then I've adjusted the valves and cam chain tension. Now my timing is WAAAAY off. I can get the points to close and spark, just not where they're supposed to. Again, I did the timing a week ago, so I don't think I burned my points that far down from one ride...

It's almost like when I adjusted the cam chain tension I slipped a tooth or two somewhere. It looks to me like I'm a few degrees off on the actual allignment between the rotor and cam. Not really sure what to do from here, but can't get it back in time. New points? Re-align cam?

Do these points look that bad? (big pic for detail)

WTF...
-MK
Is it just me or does the point gap on the left look much to wide?
 

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I think there's a chance that your spark advancer is sticky.
It happened to me on Wifey's CB200 - set the timing dead on, ran great for a while, then ran rerrible.
Check the timing, way off - chased my tail for a couple of days on it.

The advancer was dirty and gummy, would get hot and stick in the open position.
Then began sticking closed too, bike would run terrible.
The cure was to take apart the advancer and clean it up good.
 

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Discussion Starter #4
Yes the points gap is way to large, however that was after an hour of trying to mess around with the points to get them to close at the "LF" mark...

Maybe I'll just have to take apart the entire advancer and everything tomorrow and try to clean everything up. I'm not sure that's it though, because the action is consistent. I probably turned it over 30x, and it does the exact thing every time.

I'll try and dissasemble/clean/reassemble tomorrow...

-MK
 

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mktsc said:
Yes the points gap is way to large, however that was after an hour of trying to mess around with the points to get them to close at the "LF" mark...
-MK

You want the points to OPEN at the mark, not close.
 

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Discussion Starter #6
Yes I understand that they're supposed to begin opening at the "LF" mark, however I can't get them to be closed at that mark, so I can't adjust it so they begin to open there. They begin opening about 20 degrees or so before they should be with the points plate rotate as far to the left as I can.

I've also made sure that I'm not 180 off.

-MK
 

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They are NOT supposed to "begin" to open at the index marks, they should BE open (have sparked just as the indexes align).... It does sound like your cam is "out of time" but that can easily be checked using the indexes and the position of the "key" pin that drives the advance unit (without major disassembly)...
 

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Discussion Starter #8
They are sparking a good 20 degrees before they should, and I can't seem to rotate the base plate enough to get them to do it at the right time.

So how do I check the index marks on the cam, and what do I do if it is off?
 

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mktsc said:
They are sparking a good 20 degrees before they should, and I can't seem to rotate the base plate enough to get them to do it at the right time.

So how do I check the index marks on the cam, and what do I do if it is off?
I think you can just remove the advancer cam, rotate it 180 degrees, then reinstall....
 

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Bill, That's generally where I was headed... Just wanted a pic of the key pin when crank indexed to verify crank/cam timing was still on......... :D Steve
 

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66Sprint said:
Bill, That's generally where I was headed... Just wanted a pic of the key pin when crank indexed to verify crank/cam timing was still on......... :D Steve
That would be good - I don't have a 360 lying about to check (thank God)......
 

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Discussion Starter #12
So you want me to remove the points plate, advance the rotor until it's at the "LF" mark, then take a picture of the advancer cam?

Here you go:


-MK
 

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Discussion Starter #14
Yes, this is normally the point where the LH points would begin to open.

-MK
 

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I can't tell from the photo what the cam is doing exactly.
You could try spinning the cam on the shaft 180 degrees, see if that puts you in the ballpark for timing.......
 

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Discussion Starter #16
Tried turning the cam around 180, and it still won't work. It really seems like I jumped a tooth somewhere. All I can think to do is make the slot bigger in the LH points adjuster, or get a new points set...

I don't understand what could've happened to it.

-MK
 

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The pic would be the end of the camshaft with the advance unit removed, while the crankshaft is held at TDC on compression stroke of the left piston (LT, not LF) I wish to see the orientation of the "key pin" that drives the advance unit at that time..... It should be dead vertical, but IF it's down instead of up, the advance unit (and hence the breaker cam) will be 180 out...... If this is the case, simply flip the advance unit 180 and reinstall the keeper bolt and washer.... IF it's NOT vertical, the timing chain has slipped and cam/crankshaft timing is off ....
 

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Discussion Starter #18
Here you go Steve. Looks like the key is alligned right at the 12 o'clock mark when the "LT" mark is alligned. By the description in your email this indicates that the cam and crank are correctly in time.



Looks like maybe I just need new points?
 

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Yes, from the pics (I Believe) you're timed properly cam/crank-wise......
....That's possible, but I can't really see anything wrong with the points from the pics..... SOME aftermarket points were made with tolerances close to, but not quite within Honda specs and they tended to be a source of continuuing problems.... Do the points themselves have any manufacturer's markings on them?... Kokusan Denki is/was the OEM and best points, But Honda also had another supplier whose name escapes me right now...... I do have a 360 here I can refer to IF necessary (It's buried) ...... New (quality) points can't hurt.....except in the wallet .... At least it will eliminate another possibility for the source of the problem..... :? Steve

Does the advance unit have 369 stamped into it?........ Just a thought.....
 

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Discussion Starter #20
The points plate has 369 stamped on it, the advancer plate has 312 stamped on it. The only discernable manufacturer stamp on the points plate are the letters "Tec". They're also stamped on the points arms themselves.

All I can think is to replace the points. I ordered a set off eBay for $20. I'm relieved that at least the cam and crank still have a meaningful relationship...

Thanks again guys, I'll let you know once I've moved past this problem and to the next one...

-MK
 
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