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**almarconi** · 10-23-2013, 09:30 AM

If your petcock is not leaking I would keep it. If your bike has points, the dyna is a good upgrade from the stock ignition.

**Nessism** · 10-23-2013, 09:49 AM

I would not change either part unless there is a problem. The stock coils are high quality pieces. Nothing wrong with the basic design. Standard forum wisdom is to remove the plug caps, snip off 1/4" of the wire, check the caps for proper resistance, and then screw the caps back on.

Regarding the stock ignition system in general, the '79 bikes have points which work perfectly as long as they are maintained. I'd keep them unless you plan to put a bunch of miles on the bike AND you don't like doing maintenance. The Dyna S system is a good upgrade though if you aren't diligent with maintenance. Oh, and the Dyna S works perfectly with the stock Suzuki coils.

As for the petcock, I'd take it apart and inspect the interior rubber parts. Lots of people just replace the petcock but that particular model petcock is rebuildable if necessary. Good luck finding high quality replacement parts though.

**Ira** · 10-23-2013, 02:21 PM

I agree that you shouldn't replace them if they are working, but I've recently discovered neither of mine are doing their job, so check yours thoroughly.

**Nessism** · 10-23-2013, 02:39 PM

Originally posted by Ira View Post

I agree that you shouldn't replace them if they are working, but I've recently discovered neither of mine are doing their job, so check yours thoroughly.

Points maintenance is called out in the scheduled maintenance table as available in the service manual and owners manual. Sadly, many people don't bother to perform maintenance until their bike craps out, although I'm sure that is not the case in this instance though.

**Ira** · 10-23-2013, 03:06 PM

Originally posted by Nessism View Post

Points maintenance is called out in the scheduled maintenance table as available in the service manual and owners manual. Sadly, many people don't bother to perform maintenance until their bike craps out, although I'm sure that is not the case in this instance though.

points? what are those?

**TheDuke** · 10-23-2013, 04:14 PM

Well, the bike has 35k miles but is new to me, so I'm not sure if the proper maintenance was done. I will do it myself now, along with checking the fuctionality of the petcock, and keep my fingers crossed.

**Nessism** · 10-23-2013, 04:41 PM

With any old bike purchase the valve adjustment is one of the most critical details. Don't skip or you could burn up the engine. Please check the Newbie Mistakes thread linked in my signature.

**TheDuke** · 10-24-2013, 08:14 AM

Originally posted by Nessism View Post

With any old bike purchase the valve adjustment is one of the most critical details. Don't skip or you could burn up the engine. Please check the Newbie Mistakes thread linked in my signature.

I previously read through that post about newb mistakes before I started this project. I think I've checked all those boxes. Thanks for taking the time to outline some of the problems many new garage mechanics face.

**Steve** · 10-24-2013, 10:56 AM

Originally posted by TheDuke View Post

Of course, there are many complaints about the stock petcock, and a lot of people swap over to the Dyna ignition coil setup.

Are these mods worth doing before I notice a problem?

It's not so much a complaint about the petcock, it's about the poor quality of aftermarket rebuild kits for them. Let's face it, the petcock is an item that will eventually fail. Being over 30 years old and given minimal (if any) care does not help at all. If it's still working, great. If it's not, replace it. Whether you go with a vacuum-operated one similar to stock or a manual valve will depend on you. Personally, I like the vacuum-operated ones, but I am basically lazy.

Originally posted by TheDuke View Post

Well, the bike has 35k miles but is new to me, so I'm not sure if the proper maintenance was done.

Even if the previous owner told you that proper maintenance was done, assume it wasn't, unless you were there and watched him do it.

.

**bbjumper** · 10-24-2013, 12:53 PM

I have tried to rebuild the petcock on my 850 twice, two different tanks. both times it was more trouble than it was worth due to poor quality of replacement parts. Replace it with new OEM if it's questionable. Having a problem on the road sucks plus it wipes out any benefit to the budget on the repair.

**srg** · 10-24-2013, 02:05 PM

I need to replace the petcock on my bike. After doing some research, I have two options:

OEM from Suzuki itself, $120
K&L Aftermarket Replacement: $50

Any opinions on which one? Obviously I'd go with the K&L if they are equal in other aspects.