Issues with first start. Pamco, PMA, Rephase, Fresh build.

[alwaysmonday]

WhenInXS - Can you tell me where you went wrong with the ignition which was the cause for the original difficulty in starting the engine? Did you pull the rocker box and slip the cam chain backward/forward?

Jon

 

[WhenInXS]

Alright so still no luck... I went ahead and moved the cam one tooth back towards the rear of the motor. She seems to want to turn over every kick now and no more kick back. But when it starts (it has twice) it'll run for a few seconds and dies. When I go to kick it after that it is incredibly hard to kick over. Like I have to literally jump on it and it's stiff all the way through the stroke for a few kicks and will finally get back to normal. I feel like this is what's causing it to quite while running but I did every thing by the book when building. Ring gap was measured and checked out etc.. I can't think of what may cause this the pipes are hot close to the head, almost hotter than I think they should be after only running a few seconds. Carbs have been thoroughly cleaned and all known xs problems fixed (butterfly seals needle jet o-ring etc.) Thanks for the help I've pretty much lost hope for riding this summer but damn it'd be nice to hear her run after all this time/money spent.

 

[alwaysmonday]

When I installed by re-phased engine, I also experienced kick backs on every attempt to start it. I retard the timing as much as possible but still no relief. It did start and run for just a second or two in the 30-40 attempts. The final kick back one was so sever that it badly sprained by ankle and bruised by ego. This all occurred toward the end of April, 2015.

I took some time off from working on the engine to adopt our son and let my ankle heal. In June, I took the rocker box off and confirmed the cam markings on both the left side and right side were as they should be (i.e. vertical on the left and even with the machined surface on the right. The left side mark looks like it is ever so slightly forward (counter clockwise) past 12:00 Noon when the left cylinder is at TDC. The right mark is ever so slightly higher than the machine surface too (it is not bisected by the machine surface)

I am running a stock mechanical advance from the stock '79 model so that eliminates the MikesXS factor on a bad advance mech. I again carefully reinstalled the Pamco following Hugh's directions and at this point I am in the process of having a friend help me put dial indicators on the cam and piston to confirm everything is opening/closing as it should.

Jon

 

[WhenInXS]

Mine was actually how you describe yours to be. I rotated my cam one to back (clock wise if looking at cam from stator side) and it is much easier to kick with no more kick back and it fires up for about a second or two every kick now. So I'm about to start searching in other areas for some sort of mechanical drag. But in your case I would recommend moving the cam one tooth clockwise. You can see in my picture the electronic ignition magnets are just a hair off, now they are spot on flat horizontal on the bottom.

 

[alwaysmonday]

WhenInXS,
When I removed my rocker box to check the cam alignment, I also slipped the cam backward a tooth to see if I simple misaliged the cam. When I looked at it, the mark on the right was clearly below the machined surface and the mark on the left was also past noon in the clockwise direction. I take it, that this is how yours looked when you closed it up?

I thought to myself that it must be incorrect so I returned it back to the previous setting and closed it back up.

Jon

 

[WhenInXS]

Yep mine was kinda of either way you put it. this tooth or that tooth it need to go in the middle of the 2 places it could go... if that makes since. It couldn't go there obviously so I feel like this is the better of the two.

 

[alwaysmonday]

WheninXS,

Thanks so much for the encouragement to turn the cam back a tooth even when it went against the logic of everything I had been reading. I buttoned up everything yesterday, put the engine back I to the frame and let it sit overnight. This afternoon I came home from work, wired up a temporary harness and connected it to a spare battery. 6-7 kicks, no kickback at all then it fired up and ran for the first time in about 2-1/2 years. MAN THAT WAS A NICE SOUND TO HEAR!

So any more progress on diagnosing your mechanical interference?

Jon

 

[WhenInXS]

That's awesome man! I'm glad you got it running. Thankfully yes, I did find my issue. It was a washer behind the clutch basket. The Clymer manual kinda played a trick on me. And the incorrect washer I had in there made everything extremely tight. Once I swapped for the correct washer she fired first kick and ran great. Rode her about 10 miles this weekend just kinda breaking her in and getting a feel for were the carbs are at before I tear down for paint.

 

[alwaysmonday]

Great to hear.

Jon