1980 sachs 505 1d problem cutting out midrange

morgan allen /

Having a problem with it cutting in and out around mid throttle. It idles fine, and will rev up on top end.

505 1d

15mm bing clone

needle richest position

74 jet drilled to .0292 so 76

forward mount

stock sachs filter

float level correct

slip on treatland chamber

point gap .015 at tdc

21 degrees timing

Day before yesterday it ran great, then up a big hill it back fires through carb so I check the points. And oddly It closed the point gap up so I reset it, but its doing the same thing. I did notice I have a very small pin hole at the top of the header going onto the cylinder. Could this be leaning it out so much it cuts out? Obviously I need to fix the hole, but wondering if it could have that much effect? Thanks

Re: 1980 sachs 505 1d problem cutting out midrange

Overpriced Parts /

If The cam on the flywheel is rusted, pitted and or not lubed it will wear the point cam follower. Please remove flywheel and inspect before you do anything else. When corrected you can work on midrange jetting

Re: 1980 sachs 505 1d problem cutting out midrange

header hole dont matter much, could still be ignition issues, might also be the decomp leaks if you've not plugged that already. low comp makes backfires, but more in the pipe.

also quite possible that the flywheel slipped the timing, like off the woodruff key. that's "close" the gap as you suggested, and after resetting of the point gap would still have the timing off.

Re: 1980 sachs 505 1d problem cutting out midrange

morgan allen /

I don't have a puller at the moment to remove the flywheel, but I will remove the flywheel to see whats going on.

When I adjusted the points the first time the timing was 18 degrees and it ran the best it ever has.

After they closed up I reset it, but did notice the timing was it 21 degrees. So it indeed did move, but the stator was tight so I wondered if the points were getting wore causing the problem.

I did check for leaks around the head, intake, top of carb, carb to intake, intake to jug, and decompression and they were leak free.

I also took the carb apart and cleaned it to make sure there was no debris and it was good. So its definitely something timing related. Are there any safe ways to get the flywheel off without a puller?

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