Author Topic: Exhaust springs  (Read 1781 times)

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Offline bwaller

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Exhaust springs
« on: October 21, 2010, 05:13:20 AM »
I will be using a Kerker on this race engine effort and will fasten to the head with the flanges/studs. I don't see making a good seal otherwise. Is it wise to use an exhaust spring as well?

I suppose the idea is the spring absorbs vibration to help avoid the pipe cracking?

Offline Sam Green Racing

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Re: Exhaust springs
« Reply #1 on: October 21, 2010, 05:49:12 AM »
Brent, My RS just has springs. I've never had a problem with pipe breakage or the flange letting go.
Fit springs as a back up just in case, better to be sure than sorry.

Sam. ;)
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Offline turboguzzi

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Re: Exhaust springs
« Reply #2 on: October 21, 2010, 10:19:13 AM »
+1, running springs only

they are pretty strong, squash the copper seals nicely :)

will post pic later

TG

Offline wannabridin

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Re: Exhaust springs
« Reply #3 on: October 21, 2010, 01:53:30 PM »
i've always wanted to run springs, but i didn't know what the best way would be on these old 750's...  i would assume drilling a hole in a cooling fin with some meat around it, then getting some exhaust springs and welding some hoops onto the pipes and you'd be good.  the idea of bolting a steel flange and bolt to an aluminum head has never appealed to me.  you always get corrosion due to galvanic corrosion of dissimilar materials and the heating and cooling cycles will speed up this process...

please do post pics TG, i'm interested in this setup!  i'll be using a Carpy 4-1 on my build
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Offline fastbroshi

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Re: Exhaust springs
« Reply #4 on: November 24, 2010, 09:26:26 AM »
I'd be interested in seeing pics of this too.  I've been looking online and found an Akropovic exhaust install on an S1000RR.  It looks like with just the springs would allow too much movement.   ???  Is this the way your header is secured TG?  I definitely want to bin the finned collars, they must weigh 2lbs.



« Last Edit: November 24, 2010, 09:33:49 AM by fastbroshi »
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Offline bwaller

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Re: Exhaust springs
« Reply #5 on: November 24, 2010, 10:13:39 AM »
TG isn't using the exhaust collars, but I don't think the Kerker primary ends would locate well against the gasket in the head so am using the Kerker collars to clamp and the springs....well to absorb some vibration and maybe avoid cracking. Probably not completely necessary. Springs hold the mega in place.

This is not the head I'm using and have cut new shorter exhaust studs for it. I'm also going to send this pipe off for coating as it has been painted over original chrome.

Finally something complete on this race bike.  ::)

Check with TTR400 for alloy exhaust flanges, 400/500/550 primaries are the same size and I used a set of these on the last one. Nice product and a big weight savings.





 
« Last Edit: November 24, 2010, 10:16:06 AM by bwaller »

Offline iomtt9

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Re: Exhaust springs
« Reply #6 on: November 24, 2010, 10:36:19 AM »
Brent, my honda has a steel retainer with an alloy insert and the exhaust pipes fit flush over the insert which is bolted to the head. Its all held with 2 springs per pipe, never had a problem. When the bike gets back from OZ i will send you a pic of the set up.
Col

Offline fastbroshi

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Re: Exhaust springs
« Reply #7 on: November 24, 2010, 11:03:59 AM »
Brent, my first inclination was to maybe get some of those from TTR, wanted to explore my options and maybe save some $$.  I guess it would pale in regards to other money spent though.
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Offline wannabridin

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Re: Exhaust springs
« Reply #8 on: November 24, 2010, 11:24:34 AM »
i want to run exhaust springs on mine, i really like the look, but also some weight savings is cool too!  i have a carpy 4-1 that already has the flanges on the pipe.  any ideas how i could adapt springs to work on these?  i'm planning on having the pipe ceramic coated as well, so if i have the flanges dangling around, i can see that being a problem...  great looking setup though bwaller!
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Offline Howell

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Re: Exhaust springs
« Reply #9 on: November 24, 2010, 11:25:45 AM »
On our Cb500  racer I use homemade alu flanges without springs , reliable and light.
A friend of us uses also alu flanges with only one spring at each pipe.
« Last Edit: November 24, 2010, 11:28:14 AM by Howell »
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Offline turboguzzi

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Re: Exhaust springs
« Reply #10 on: November 24, 2010, 12:21:08 PM »
Wow! pics from Brent! Hallelujah!

forgot to post mine. not that the 500/4 vibrates that much but with this set up nothing cant break.

"what is not there cant break" somebody said and i add: it doesnt weight either :)

more to the point, what i like about springs only is that they fully expose to the air the hottest point in the motor, the exhaust flange, no dead air pockets there.






Offline 754

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Re: Exhaust springs
« Reply #11 on: November 24, 2010, 01:19:43 PM »
I will say this, spings should work if the pull straight in, Apros do not even come close.

 I dont see any real advantage timewise over a 1bolt clamp.

 I do however think that pipe may run a tad cooler coming out of the head.
 Someone on here, silver CR ?, made some really nice spring anchors, that went onb the 750 studs..

 The springs that Apro uses look just like Harley kickstand springs, probavly with a bit less pulling force..
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