No exhaust crossover

[mike81]

I have an 81 SH that I am restoring. My goal is to make it 'not special' i.e., as much like a Standard as I can.

I have a 4 gal tank from a '75, flatter bars, etc.  I mounted headers from a Standard intending to use EMGO mufflers, but there will be no crossover between the pipes.

I understand the crossover can add low and midrange power, and that each cylinder is effectively serviced by both mufflers with a crossover.

What problems can I expect from not having a crossover? I just rebuilt the air filters and removed the carbs to service them, and now is the time to re-jet if warranted. Thanks!

  

[5twins]

You shouldn't encounter any problems. Early models had no crossover pipe. If you did happen to lose a small amount of power, it would be gained back by using freer flowing mufflers and by some minor carb re-jetting. The BS34 carbs on your '81 model were set up very lean from the factory. Any changes to intake and/or exhaust can throw off their state of tune, usually making it too lean. It would probably be a good idea to bump the mains one size (132.5 stock to a 135). The idle circuit may need to be richened up as well but I'd let that go for now until you can run the bike and see if it needs it.

[mike81]

Many thanks, 5twins.  Some liquid wrench and patience and now all float bowl screws are loose!  I will hunt out the 135 main jets and just hope the float bowls don't have too much dry gas varnish inside.

I am really looking forward to riding this bike, hopefully this year. I just realized the brake master cylinder from my 85 Honda Sabre (same bore size) will serve with the double discs (from an XS1100) I will install. The bars are from my 84 Nighthawk S, headers from a mid 70s XS, as is the 4 gal tank, tho that needs re-lining. Petcocks already rebuilt.  I'm getting WAY ahead of myself here but I also have a right side case cover already tapped for oil lines + oil cooler) - but first I should get it running...

It did run when I got it from an estate sale in 2010 for about $425 with 11K miles, tho it was NOT roadworthy.

Time. Time and motivation. And good advice. Thanks!