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Starting issues!
- Thread starter mattg666
- Start date
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- build electrical engine how to
DIRTY DOG
XS650 Guru
I just checked mine and the little pins (on the adv rod ) are 180* apart from each other as I stated in post #20 not sure if that will help or not
Well, let's have a look at it thisaway.
For the normal rephase,
where the rightside crank is advanced 83°,
and the stock cam is cut/twisted/welded to match the crank, at 41.5°,
then when at Left cylinder TDC (firing),
the advancer should look like this:
However, you have a custom (non-Yamaha) Megacycle cam, configured for the normal 277 rephase.
We've already established that the cam-to-crank alignment is okay.
But, your ATU isn't pointing in the same direction as it would for a twisted stock cam.
Since it was made by Megacycle, they drilled the indexing hole for the ATU backing plate.
Is it in a new place compared to your old rephased stock cam?
Is this a new configuration, which would call for different setup, or parts?
Is it a mistakenly missdrilled hole?
For the normal rephase,
where the rightside crank is advanced 83°,
and the stock cam is cut/twisted/welded to match the crank, at 41.5°,
then when at Left cylinder TDC (firing),
the advancer should look like this:
However, you have a custom (non-Yamaha) Megacycle cam, configured for the normal 277 rephase.
We've already established that the cam-to-crank alignment is okay.
But, your ATU isn't pointing in the same direction as it would for a twisted stock cam.
Since it was made by Megacycle, they drilled the indexing hole for the ATU backing plate.
Is it in a new place compared to your old rephased stock cam?
Is this a new configuration, which would call for different setup, or parts?
Is it a mistakenly missdrilled hole?
Ok checked it, and the locating pin on the mega cycle on the advanced side is at like a dead 6 o'clock when the left hand side at TDC... Just eyeballing my Hughes cam, with the indexes marking straight up and down like it should be installed with the left cylinder at TDC, it looks like it's at about 1-2 o'clock... Just holding it next to the motor in the position it should be sitting in...so I guess the locating pin got drilled wrong? Or they did it on purpose and I have to move the pin on the timing side 180degrees?
Okay, that 1-2 O'clock approximates the 41.5° twist done to the stock cam.
Sure sounds like it. I think you're getting closer.
Maybe on purpose, dunno. Have to ask Megacycle about that.
Otherwise, you'd need something that would offset the added/missing 41.5°.
180° movements won't do it.
Essentially, that would show up as 83° off with the ignition timing.
No wonder it was spittin' at ya.
Twist the Pamco rotor?
Reposition the Pamco plate?
All it takes is something close to 41.5°...
Just rotated the rotor with the trigger magnets on it to the next keyhole and set the timing playe all the way advanced and it wants to go, it's igniting more but still no dice... And I can't advance it anymore because the circuit board is in the way... Otherwise I'd just seemed out more off the plate to be able to rotate it more
Just reread your "6 O'clock" and "1-2 O'clock" post and realized that there may be a 180° AND a 41.5° issue.
I think you've got a good grasp on the problem.
Now, the challenge is to get the timing close enuff to run.
I've never done a rephase, don't have one, never even seen one.
Best I can suggest at this point is to study the Pamco setup, figure out how it fires for the left cylinder, figure out how it fires for the right cylinder, figure out which pickup fires the left, figure out which magnet fires the left.
In my mind, I'm thinking that the misdrilled pinhole has your ignition retarded 83° (at the crank).
That, plus the possible 180° at the advancer (or advance shaft)...
I think you've got a good grasp on the problem.
Now, the challenge is to get the timing close enuff to run.
I've never done a rephase, don't have one, never even seen one.
Best I can suggest at this point is to study the Pamco setup, figure out how it fires for the left cylinder, figure out how it fires for the right cylinder, figure out which pickup fires the left, figure out which magnet fires the left.
In my mind, I'm thinking that the misdrilled pinhole has your ignition retarded 83° (at the crank).
That, plus the possible 180° at the advancer (or advance shaft)...
There's a trick that can be done with diagonal cutters.
*warning* - This usually ruins good/sharp cutters. Mechanics usually have old cutters for this.
Grip the pin with the cutters, as though you want to clip it as short as possible.
Lever the cutters, pushing the handle downwards (or upwards), as though you were levering/pulling a nail out of a board.
*warning* - This usually ruins good/sharp cutters. Mechanics usually have old cutters for this.
Grip the pin with the cutters, as though you want to clip it as short as possible.
Lever the cutters, pushing the handle downwards (or upwards), as though you were levering/pulling a nail out of a board.
Too bad you're not down thisaway. We'd have this thing licked.
I have some "parallel jaw pliers", like this, that have very high grip power, and a notch running down the center that grips pins. They are my 'goto' for stubborn pins.
There's a couple threads in here where members have posted their methods of removing those pins.
Searching "advance shaft pin", or similar, may bring those up...
I have some "parallel jaw pliers", like this, that have very high grip power, and a notch running down the center that grips pins. They are my 'goto' for stubborn pins.
There's a couple threads in here where members have posted their methods of removing those pins.
Searching "advance shaft pin", or similar, may bring those up...
Right on! I appreciate it! Shit I just passed through Fredericksburg about a year ago heading to a chopper show in new braunfels... I'll be heading there again in less than two months so I need this sucker going so I can put miles on it before hand.
DIRTY DOG
XS650 Guru
did you get it fixed yet??
Well kind of.... I took the motor out and checked the cam along with TDC and I was about 5 degrees off so I pressed the sprocket off and put it back in and it was landing right on the money according to the mega cycle time card. So I pop it back in and go to kick it and nothing again. I advanced my ignition plate all the way advanced and kick it and it starts but runs very rough and dies. So I checked out the carbs, they were flooding my cylinders. So I took those off and went back to my original 1-2 intake setup and tried starting it... It worked better... And wasn't flooding my cylinders... But still would die and run rough. So I figured it had to be my ignition timing so I modified my plate some so I could advance it a lot more... And boom... It worked. For some reason, that ignition just won't advance enough... So it runs, but I'm still trying to go back to dual carbs so I have to figure out what's up with them... I'm assuming my float level is way too high... And probably install the power Dynamo ignition since it fires off of the position of the crank and not the cam... That way I can pick exactly where it fires not just have limited range. So yeah, kinda fixed it hahaha I know what the problems are now... Just takes a little time and money from now on haha
if you had listened back in January you'd have had it running weeks ago but you just refused to consider that your cam timing could be set wrong .
'your cam timing must be off
'
well no hard feelings
I'm genuinly glad that you are getting there. We only respond to peoples requests for help because we all enjoy helping others as we have been helped ourselves.
good luck
'your cam timing must be off
'
well no hard feelings
I'm genuinly glad that you are getting there. We only respond to peoples requests for help because we all enjoy helping others as we have been helped ourselves.
good luck
Although yes my cam timing was barely off that's not really the issue, and still wasn't really, it's my ignition plate not being able to advance enough to fire it. I had to completely modify my ignition timing to fire appropriately which I shouldn't have to do and I wouldn't be able to run it like this permanently... And with that being Said, even with it barely off on my cam timing, it should have still been able to fire within the range of the ignition plate slots if the ignition plate was even close at all.... But good job on STILL thinking I didn't try people's suggestions, when I clearly did... I just went ahead and dialed my cam timing in while I had the tools and he motor out... But it still wasn't really the issue...
running out of adjustment on a ignition timing plate is a classic sign of the cam timing being off . you said that you adjusted it a bit my bet is that you'll end up adjusting it some more before the bike will run properly .
