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Suzuki Savage Backfiring Issue

48K views 35 replies 13 participants last post by  Shipwreck 
#1 ·
Hey everyone.

From what I've read, the Suzuki Savage is known to have this issue. Mine does as well, as its getting progressively louder all the time, to the point where its rather embarrassing to ride it.

Is there any solution to this? Or a way to dampen the sound?

Thanks for any replies.
 
#28 ·
No lapping the valves (with a compound, OK), (re-seating them as the machine shop did with angled stones BEST) On the head they just mill (re-surface) it about .0010 inch or so to make it even again. On the chain I think that OEM is the only way to go, just make sure to replace it, the spring, and the slipper when you replace the chain.
 
#29 ·
Change of Riding Style to prevent Backfire



The Suzuki Savage is delivered running very lean for environmental reasons. That means it will accumulate unburned gasses in the exhaust pipe at shut down and they in turn will find a hot spot in the exhaust system and kablam - you get wild backfires everytime you decelerate or shut down.

Over the 10 years I have ridden my Savage I have learned to modify my riding style to reduce this to a minimum. My trick is as follows

When slowing down and using engine braking only do so with the throttle fully closed. Keep your speed up until you are ready to make positive throttle changes - then completely close the throttle - this will reduce the amount of intake gasses getting into the exhaust pipe during the period of engine braking and will reduce the backfires to a mild wuff - still there but not shotgun sharp and loud

When shutting the engine off - let it run for 5 seconds at idel before cutting off the ignition. It will pop but not quite so loudly.

Regularly I ride my Savage on the highway at 100-110 kmph. A few 10 mile runs at steady speeds will blow a lot of carbon out of the exhaust pipe - it is the carbon that is the source of ignition when the bike backfires. Reduce the carbon - reduce the backfires.

Hope these tricks help you too
 
#30 ·
The first picture is the one of my old air cleaner, lets just say I bought a brand new one. The rest speak for themselves.[/QUOTE]

You have posted almost classic pictures of the oil that accumulates on the Suzuki Savage enigine as a result of a leaking "head cap seal"

The problem looks like a head gasket but in fact the problem is in the valve/cam well at the top of the cylnder head.

I have not discovered what year your Savage is but this problem certainly is well known on Savages produced before 2003 - I am not sure that the newer ones also have the problem but I do not follow Savage boards very frequently any longer so am not aware of what is happenning with newer bikes.

the Head Cap Seal costs around 20 bucks and can be changed without removing the engine from the frame. It is an all day job though and fiddly so you might want to consider having a the work done at your5 Suzuki dealership
 
#32 ·
Suzuki Savage Backfire



This too is a well known issue with the Savage engine. The design of the carburation system causes the engine to run lean and hot - a spot of carbon in the exhaust pipe will get red hot and when unburnt gasses hit it during deceleration or when shutting off the engine - kablamma!

There are a couple of fixes - and you will have to search for the exact procedure to deal with the first one.

1. You can raise the needle in the carb - this involves drilling out a brass plug to allow access to the low speed idle adjustment screw and and shimming the needle to get more gasoline into the engine. Search for detailed instructions on this one elsewhere on the net.

2. Take your bike out for a long steady run on the highway at 100 kmph - this will give the exhaust system time to burn and blow out most of the accumulated carbon and will reduce the hot spots causing the ignition and backfires. You need to ride 20 or 30 miles to burn all this carbon out

3. This one is the most difficult - change the way you control the throttle. What I mean by this is use the throttle more like an on off switch. Do not decelerate with partial throttle open - when you go to slow down - close the throttle completely. This will reduce the amount of unburnt gasses getting into the exhaust pipe and the backfires will be reduced from a sharp crack sounding like a pistol shot to a mild wufff -

Good luck - yours certainly is not the first or only observation of this problem

Cheers
Polar Pilot
 
#33 ·
Perhaps this will help:

Savage Backfire
(from January 1997 RIDER magazine's Tech Q&A)

Q) I purchased a new Suzuki Savage 650 last July. From the very beginning the motorcycle would backfire when decelerating or coming to a stop. I took it back to the dealer twice before the 600-mile service, and complained about it at the initial service. I have tried different grades of gasoline and they seem to have no effect. The dealer has told me that I should expect backfiring with the design of this engine and that it should decrease as I build up mileage. I have 900 miles on the bike now and backfiring doesn't seem to be decreasing. I have found other riders of Suzuki Savages that are having the same problem. - Jay Coney, Kerrville, Texas.

A) This column receives a lot of mail over the course of a month, and the single biggest gripe among our readers are problems with lean-running. late-model carbureted bikes. The poor old LS 650 really suffers at the hands of the EPA, and I certainly sympathize with you, Coney. We can fix it, but first let me explain the hows and whys.

When the throttle of any engine is rolled or snapped shut, some fuel is drawn through the engine and kicked out the exhaust without being burned. In abundance, this raw fuel vapor can be smelled, tasted - and when light is passed through it- seen. It's referred to as photo-hydrocarbons or more commonly smog. Yes, there are several other pollutants coming out of the exhaust, but the human senses can't detect them. The manufacturer of motorcycles have three methods of dealing with excessive hydrocarbons. Forcing air down into the exhaust port with an air pump and diluting the outgoing fuel vapor is one method. Kawasaki pioneered this method with their 'Clean Air System', which employed a vacuum-driven pump that puffed air through reed valves placed over the exhaust system. A 'cat' is nothing more than an oven which bakes the hydrocarbons, burning them off.

The most common method is to simply lean out the carburetor. The low-speed and midrange circuits of the late-model carburetor are not adjusted to give optimum performance - they're set up to produce a minimum hydrocarbon count on deceleration. What miserly amount of fuel they do deliver to the combustion chamber when the throttle is closed causes misfire and an audible afterfire in the exhaust pipe. Now, I haven't mentioned fuel injection or other exhaust gases. As I said, the bulk of complaints from readers of this column is deceleration backfire and also poor idling of carbureted engines. No doubt we'll get around to discussing other emission-control devices and their problems in future issues.

Getting back to your Savage 650, Coney, here's how we can specifically cure its problem. We need to richen those two areas of the carburetion curve that are factory set on the ridiculous side of leanness. Remove the diaphragm slide from the carburetor and look down inside its bore. Two small screws hold a plate over the slide needle.

Removing the plate, you'll see a small, white plastic spacer with a hole through it sitting on top of the needle. Throw that spacer away and reinstall the plate. A spring under the needle clip will now push the needle up to the plate occupying the space vacated by the white spacer. The distance that the needle has been 'lifted' is the thickness of the discarded spacer - and that's ideal. With the needle raised, more fuel will flow by it, meeting the actual needs of midrange running.
We can also fatten up the low end of your bike's carburetor by turning out the low-speed mixture screw. To gain access to this screw, you'll need to drill out the brass plug pressed in over it and yank it out with a sheet-metal screw attached to a slide hammer. You'll find that plug up high on the right side of the carb about where the mouth enters the carburetor. Usually Suzuki applies a splash of white paint over the brass plug so that it's immediately noticeable. With the engine warmed up and idling, turn the mixture screw out incrementally until you achieve the highest idle. There will be no doubt in your mind that you're making progress because the idle will come up and sound stronger. At this point, turn the idle adjuster knob out and bring the idle back down to a leisurely gait.

Just these two, relatively simple adjustments will not only eliminate the backfire, they will make an amazing improvement in throttle response and driveability.


Visit http://www.suzukisavage.com where there is lots of help for us thumper owners.

Cheers,

Mike
 
#34 ·
Mike, once again, thank you for the article. Great info for all of us who deal with the backfire problem. My company has a parking garage and the motorcycle parking is right next to the smoking area. I've had several mornings where I'll pull up, shut down and....POW! People almost s*** themselves it's so loud in that garage. Funny, but not.
 
#35 ·
No problem, Shipwreck.

I don't know if the OP is still onboard, but now that I know the Savage a bit better, I agree with polar pilot about the leak. That looks like it is originating right at the plug which is in the recess behind the exhaust, on the bottom side of the head cover. It can fool you because the wind blows the oil all over the place and when on the stand, of course, the oil accumulates on the left side as shown in the pictures. I still have that little job to do on mine.

I have found also (I think and am about to prove or disprove it) that the decomp lever not releasing or not being adjusted correctly can increase the backfiring, too.

Cheers,

Mike, finding out how "special" the Savage is lol
 
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