Head pipe mismatch

Finishing up 1965 Atlas. New 1 5/8" head pipes came with the bike so who made them is unknown. They appeared good quality. Left side pipe fit like a glove, tucked-in top to bottom to about 3/4" frame clearance, center stand arm clears even around, and muffler hanger bracket lined up and bolted up easily. Right side pipe not so good. Did not have the 3/4" or so vertical tuck-in of the left side so straight down and back at least 1 1/4" out from the frame tube. With muffler slid on the head pipe the mounting holes are almost 3/4" away from the hanger bracket. A bit of muscle does bolt up this side but this cannot be right. It looks OK from the side but front-on, I notice the difference. If the right side head pipe had the same tuck-in as the left side, it would have fit just as easily. Bend in the lower corner of the pipe? Not in place, a disaster in the making!! I have a machine shop, perhaps make up a steel slug internally threaded to accept the pipe and a spare finned collar. With the slug held in a vice and a round piece at the upper pipe bend radius, perhaps the lower front corner could be carefully pressed inward protecting the chrome with a flat or radiused piece of Alumimum or wood? I don't believe Waldridge, Andover, etc., would sell me just the RH pipe.

The exhaust pipes situation has been tarnished of as late due to the same people who made good pipes not making them anymore, so everyone was in the same boat, more or less.
If you don't mind pipe blueing on the chrome, you can heat up with a plummers blowtorch and ease the pipes into a better position , but avoid leaving a kink.
You should not have to force this pipe when cold into position, or it will in time fracture/split.

Thank you Bernhard. I was thinking that if the engine was run to the point of natural bluing that stress from the force-fit would relieve. For now, I lean toward the machine shop approach being I have all sorts to work with.

dougs bikes said:

Thank you Bernhard. I was thinking that if the engine was run to the point of natural bluing that stress from the force-fit would relieve. For now, I lean toward the machine shop approach being I have all sorts to work with.

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the header will break with a force fit (best case scenario) and strip out your head's exhaust threads (worst case scenario).

if you're going to bend the pipe with heat, fill it with fine dry sand and plug the ends. an oxy-acetylene torch with a rose bud will create your heat >>a lot faster<< than a propane, butane, or map gas plumber's torch. clamp the header in a vise, apply heat to the outside of your intended bend, and slowly bend it when dull cherry red. you won't need a die.

do it outside and wear a respirator. you will kill the chrome.

On my 63 Atlas (actually a 62 build), the right side has a significant tuck in to provide clearance for the tach cable. I am not with the bike now or I would take a picture. PM me if you think a picture would help.

Slick

texasSlick said:

On my 63 Atlas (actually a 62 build), the right side has a significant tuck in to provide clearance for the tach cable. I am not with the bike now or I would take a picture. PM me if you think a picture would help.

Slick

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Slick, I think you have a very rare original pipe. Think they stopped making the tuck in early on - maybe in 1962.

Bodger said:

Slick, I think you have a very rare original pipe. Think they stopped making the tuck in early on - maybe in 1962.

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I think my Atlas is indeed very rare ..... it came new with a 6 start oil pump and big end squirt holes, and runs away from other Atlii.

I wish someone could tell me what I have .... I think it was a special factory build, for evaluation by Berliner, then I lucked out when Berliner released it.

Slick

If you intend to heat and adjust an exhaust pipe, I recommend getting pipe from a cheap car parts supplier first. Just to practice on. To me it took only four tries to get a decent small bend without getting a kink. Took a while to figure out where and how much to heat. But I have done some pipes before with sand filling. To do it on a open pipe is different and much harder. Don't expect to make more than slight adjustments without sand filling.

Found this image on my phone .... shows tuck in.
EDIT: 5.2.21 ..... Better pics with left side for comparison.


and left side,