Author Topic: exhaust kinks  (Read 482 times)

Offline Rimmy

  • Posts: 372
exhaust kinks
« on: Nov 17, 2017, 15:44:25 »
Howdy all,

I'm putting the CL scrambler pipes on my CB350 with a set of quieter core mufflers from Cone Engineering.  Anyhow, I need to add a kink to the exhaust so they 1) clear each other and 2) clear the rear shock.  They're barely touching so not much is really needed, but my question is...

How much room should I make between the mufflers and the rear shock? Is heating the shocks up even really a concern?

Offline Jewbacca

  • Posts: 1153
  • Therapy is expensive. Riding is cheap. You decide.
Re: exhaust kinks
« Reply #1 on: Nov 17, 2017, 16:49:18 »
It shouldn't be an issue as long as it's just the muffler and not the head pipe. 1/2"-1" would be fine so much as when it flexes there's no contact.
1979 Honda CB750K- Soon to be CB750K-SC Night-Ninja (SOLD)
1974 TX500A "Yamahonda""
1983 Honda CB650SC
Gives me a major cramp in my wedding tackle..." Fellow PNW Rocker Dave Simmons

Offline jpmobius

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  • Posts: 1227
  • where does this go?
Re: exhaust kinks
« Reply #2 on: Nov 17, 2017, 19:21:16 »
Right, as long as there is no contact considering any flexing.  Presumably your rear suspension flexes nearly zero (unless you ride like a maniac or the assembly is worn to death, or is antique enough to be sufficiently frail) so the pipes are the biggest consideration.  Temperature is really a non factor as even the tiniest air space is enough to keep anything from getting too warm - the shock body being the only potential issue as the damping fluid gets hot enough by itself, but the spring will create loads of clearance automatically.  If you can't manually tweak your pipe close enough to touch anything you will be fine.  I have one bike with maybe as little as 1/16" of clearance from shock fastenings and even though rubber mounted, they're stiff enough to never contact the moving suspension.

On a long enough timeline, the survival rate for everyone drops to zero.

1973 RD350 Yamaha build

Offline Rimmy

  • Posts: 372
Re: exhaust kinks
« Reply #3 on: Nov 17, 2017, 21:31:24 »
Thanks for the replies, I'm glad to know that I shouldn't have any problems with just a bit of clearance. I just got done rebuilding the swingarm with new bronze bushings and I don't really anticipate beating the pants off of this bike, so flex should be minimized. Will be busting out the torch tomorrow morning to make some minor clearance!