Author Topic: pin holes in stock exhaust system. Solution?  (Read 665 times)

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Offline gregwaits

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pin holes in stock exhaust system. Solution?
« on: October 06, 2008, 05:51:22 AM »
My K8 still has the stock 4-4 pipes. In general, they are very clean in appearance with no dents or rusted through spots.

However they do have numerous pinholes throughout. When the bike idles, you can see puffs of smoke occasionally.

Are there are fixes for small holes like this? Or am I a doomed to see the pipes slowly go to seed?
1978 CB750K8; 1970 CB450

Offline andy750

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Re: pin holes in stock exhaust system. Solution?
« Reply #1 on: October 06, 2008, 06:07:39 AM »

I had 2 pinholes in my HM300 pipes last year...fixed it with JB Weld...and its held up over this last year (+3500 miles).

Good luck
Andy
Current bikes
1. CB750K4: Long distance bike, 17 countries and counting...2001 - Trans-USA-Mexico, 2003 - European Tour, 2004 - SOHC Easy Rider Trip , 2008 - Adirondack Tour 2-up , 2013 - Tail of the Dragon Tour , 2017: 836 kit install and bottom end rebuild. And rebirth: http://forums.sohc4.net/index.php/topic,173213.msg2029836.html#msg2029836
2. CB750/810cc K2  - road racer with JMR worked head 71 hp
3. Yamaha Tenere T700 2022

Where did you go on your bike today? - http://forums.sohc4.net/index.php?topic=45183.2350

Offline gregwaits

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Re: pin holes in stock exhaust system. Solution?
« Reply #2 on: October 06, 2008, 06:08:57 AM »
Thanks Andy  :)

I have a couple tubes of that in the shop already. Worth a try!
1978 CB750K8; 1970 CB450

Offline heffay

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Re: pin holes in stock exhaust system. Solution?
« Reply #3 on: October 06, 2008, 08:04:16 AM »
if you have pinholes... they are probably pretty well gone on the inside as well.

not that they can't work for a long while to come, but yes, they are probably on their way out.
Today: '73 cb350f, '96 Ducati 900 Supersport
Past Rides: '72 tc125, '94 cbr600f2, '76 rd400, '89 ex500, '93 KTM-125exc, '92 zx7r, '93 Banshee, '83 ATC250R, 77/75 cb400f