Aligning 750 exhaust pipes

aircooled1

aircooled1

New member
Location
Concord, CA USA
I had taken off the muffles to have easier access to the gear selector cover on right engine side. See my other "blue loctite question that was answered). After finishing the gear selector adjustment I reinstalled the mufflers + exhaust pipes that I had loosened the nuts on that hold the exhaust pipes to the engine exhaust ports on the head). When assembled again I was worried on clearance of the exhaust pipe Right Side that was real close to the nut holding the back axle on. Hmmm. I would like advice on if you think the pic shows too close? And if it is what to loosen for exhaust system and what to jiggle and tighten in what order? Just checking with you all before I attempt more. Thanks. I include pic of Right muffler showing very close (Horizontal) position to the axle nut and Left Muffler with shows lots of clearance (Horizontal) and the . Thanks!
 

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The two headers aren't actually symmetrical and sit at different distances from each side of the motor. So it's not uncommon to have a slightly different muffler position - on later SFs this becomes evident if you remove the big junction box.

If your header pipe on the RHS is close to the motor then there's no way you can adjust it to get the muffler to project at a different (wider) angle to create more clearance to the axle nut. You could check the position of the muffler brackets on the frame - the more inboard they are, the closer the muffler will be to the axle nut ... obviously! Some tweak bending may help.
 
I have a set of big bore headers and collector on my 3c, it bearly fits between the frame rails and add in the centre stand and getting even clearances off bits and bobs right down through the bike isn't easy and by the time my mufflers go on getting them even and not poking way out is a mind F. These mufflers were not designed to fit this system and I think the built-in angle cut they have isn't probably exactly correct, the last time I did it I ended up going full S and M. The exhaust was loosely fitted and I looped a length of 10mm thick rope around the ends of the mufflers and twitched a very long Philps head screwdriver through the rope and twisted said rope to eye-popping tension pulling the rear of the mufflers inwards and then tightened the rest of the exhaust. It's now better than it was. It's a full-blown wrestle mucking about with exhausts. The best tip I ever saw was in Reds shed during an Insane assembly thrash putting my bike together the second time in 2 days, Dont Ask. At 10pm with Red Paul Bret me and Mark throwing bits on, one smart bloke was off in a corner sanding and oiling the exhaust connectors clean and smooth and carbon-free, which made that part of the job so much easier. That bunch of blokes was like a well-oiled team. Anyway, thanks Paul, 20minutes cleaning exhaust connects saves so much horrible grunt work that night. I now do exactly that if the exhaust comes off again.
 
The lower Rhd Screw for the Shock
is mounted in the wrong direction.
Head of the Screw must be outside.

Nr. 4 / 5 in the Picture

Kapitel 14

SCHWINGE, STOSSDÄMPFER, LUFTFILTER GT,SF3
www.laverda-paradies.de

Regards
Rainer
 
Yes to the above regarding the need for the thin nut on inside. Wondering if by chance you’ve run the bike w an exhaust not containing the cross over pipe, and which seems better. My 750 SF came w a Malcolm Cox exhaust that lacks the cross over and the bike seems anemic in the mid range.
 
Thanks for comments on this. I will take note of switching the orientation of the bolts on the bottom shock mounts so the nuts are inboard. First I need to get thinner nuts to do that. I think previous owner had switched them as the stainless steel nuts he used were too big to fit inboard. I did end up trying to get a bit more clearance in right side where exhaust is closest to swing arm but alas did not get much more clearance than a couple millimeters as I held it away from swing arm and tightening the exhaust clamp. In test rides - no problems of muffler coming in contact with the swing arm so I will leave it for now. Might get a black rubber washer that would get me a bit more clearance on the Right muffler if I put it next to the other one that affixes muffler to frame. p.s. To TeddyG question if I have ever tried no cross over pipe - answer is no. Bike came with cross over pipe and have always left it as is.
 
There are 'crossover pipes' and crossover pipes - the older models have the pipe between headers up near the head - most think of the SF1/2/3 crossover pipe under the motor at rear. I don't think anyone would remove that crossover from the headers - if I'm right, you'd need use the later headers and then the entry to the head is different. I actually went sort of the other way, converting a small valve head to later type headers.
 
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