building a new flame sucker

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NickG:
Jack,

Pity it didn't run first time but I don't think these things ever do!! I'm sure it'll have a better chance with the modifications you have done though. I'm having reservations about mine being able to run now, even though it is supposedly easier to get poppin to run! They really are finicky little things, or in your case finicky big thing!

Good luck, think you're there though. Lightened lever looks great by the way.

Nick

madjackghengis:
Hi all, appreciate the comments Stew, Gerhard, David, and Nick, I'm glad someone wants some pics of the die filer, I bought the kit, took a rather short time to build it, and have used in quite a bit since, and it is a very nice addition to the shop. I will go through the drawings and post what I can, and take some pictures, and post a log on it in the machine section, and link to you, Gerhard.
I had a short day yesterday, my 27th anniversary, spent most of the afternoon getting a 51 Harley pan head ready for its first start after a bike build, just about an hour's of niggling details and it's ready to fire up, but we spent about four hours on other "niggling details" yesterday, last wiring, fuel lines, oil lines, double checking everything, timing and the like, a good friend's bike, been down for four or five years, and has very few parts that ever ran together before. A 1937 frame, fifty one bottom end of the engine, 75 top end, that is heads cylinders and pistons, new carburetor 1930 something springer front end, and 1940 wheels and brakes (ugh), been in my shop for about three years kind of like a hobby shop garage for down and out mechanics. It would be running except the two years of ecconomic relief didn't include mechanics and motorcycle repair business, just wall street.
I got things sorted out pretty much on the flame eater, with the cam about in the right place, and with the right diameters and it should be close on the overall timing, but I think I need a bit larger valve cover, I think I turned the one I had, down about a sixteenth too small, making for a bad seal on the vacuum side. If this doesn't get things running, I think I will re-arrange the valve levers and see about inserting a "poppin" style valve train, and valve, as that seems to be about as light and minimal valve train possible for such and engine and I think I'm getting the oil on my sliding valve carrier sticky from getting too hot. It stays in the flame, open and closed, and probably shouldn't. I really like the way the "poppin" valve gets totally out of the flame when it's open, and only exposed to it during the short cycle while closed, and able to dissapate heat into the head. Thanks again for looking and for comments, and I think you will enjoy the die filing machine write up, I know I would be kicking myself if I hadn't built it, I tried many cheap and easy ways around it, but none were sturdy enough and solid, to give a squared off finish, and to keep going without dying on the filings. On top of all that, I've got a great wife, she's happy we didn't go anywhere so she didn't have to get dressed up, and she enjoyed the Chinese I went and got, from our favorite Chinese takeout, about an hour away, some things are a bit away when you live out where the deer and the bears play. It's good to have a wife that puts up with all our kind of mess, and doesn't want to get all dolled up on an anniversary and was ready to come out and cheer if she heard the sound of that Harley fire up. :beer: cheers mad jack

Brass_Machine:
Hiya Mad Jack :wave:

Dunno how I missed this thread. Nice work! The pictures are excellent. Now that I have read this thread from beginning to end in one shot, I am anxious to see it run.

BTW... Happy Anniversary!

Eric

madjackghengis:
Thanks for all the kind remarks, this has been a challenge, trying to apply several different ideas into one engine has meant lots of learning. The sliding valve worked great, but the heat burned the oil and caused the slider to stick, so I chose to go with a piece of spring steel pivoting on a spring loaded screw, a leaf from a feeler gauge found on the bench, about .013 thick, punched a hole for the pivot, used a hacksaw blade with the gauge in a vise to cut a slot for the pin to ride in, and drilled and tapped a #4-40 hole in the head for it to pivot on.

it's the same pin which moved the slider up and down, but I had to change out the roller on the arm, as the pin was in the wrong position for the valve to close, so I found another ball bearing, .750 o.d. .250 i.d., replacing a .625 o.d. .1875 i.d., and had to turn a pin with a shoulder to hold the new bearing.

old and new bearing with pins in place

another view of them

here's another view of the engine with its new valve, still not running, but I need to alter the cam, I think it's open too long, not getting enough of a power stroke. I will be doing some work on it today, and hopefully getting somewhere. If this valve arangement doesn't do the trick, I think I will coble together a version of the "poppin" valve set up, as it seems to be about the most effective and least presumptuous with regard to stealing power. This engine is going to run if I have to put another cam, two pushrods and a spark plug on it, one way or another. So on to another round of modifications, and trials. Ta ta for now, mad jack

NickG:
Hi mad jack, your new valve looks good, having just finished popping I can say the thin valve works well giving a good seal. I was worried my valve wouldn't be shut long enough but then realised on poppin that the only timing that really matters was the point at which the valve shuts since on poppin the valve is not forcibly opened by the cam. Only by spring pressure. But if there Is still a low pressure in the cylinder it will stay shut until it needs to open when there is an over pressure. On yours i noticed your cam operates In opposite way. It forces the valve open. I know the geometry won,t be right but If the ARM was on top of the cam it would shut the valve at a chosen time but with a sufficiently light spring pressure it wpuld, in effect be automatically openef when required. Hope this helps, trying to do it from the wife phone so apologies if it doesn,t make much sense I can hardly see the trxt!

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