My Apex is Backfiring. Any suggestions are welcome.

[Exciter Man]

I was out the other day and was running about three quarter throttle when I inadvertently hit my kill switch (Don’t ask, I was reaching across to adjust a handlebar gauntlet). I quickly tried to reset it but by that time I had coasted a fair distance. Not realizing it at the time, my primary clutch was still engaged, so as soon as I reset the kill switch, my engine fired back up. Of course at the same time, my machine backfired rather loudly. From then on, whenever I let off the gas and coasted or if I hit the brakes to slow down, my engine backfires.

I checked the Internet briefly to gather some information on backfire or after fire and there are many varied opinions. One article specifically states backfiring will cause no engine damage. It had to have done something because my sled has never backfired before and now it won’t stop. I have had same say I could have bent an exhaust valve, blown an exhaust gasket (sled not running any louder), affected my timing, etc. The sled was running a little rough prior to the incident and I thought I might have had a plug going. When I started it cold last night for the first time since the incident, it idled roughly but when I drove it, it has not lost any noticeable power. The backfiring, however, continued unless I maintained a little throttle while slowing down.

If anyone has experienced similar problems, I would appreciate any information.

 

[MCApex44]

How many miles on your sled? Backfiring will start once your exhaust donuts have failed and need to be replaced. It happened to me and many others at around the 3,000-4,000 mile mark. When you start your sled and it is cold...listen for an exhaust leak (puffing) underneath the gas tank area.

 

[Exciter Man]

7500 km / ~4600 miles

Thx for the info I will check.

 

[MCApex44]

I would bet $2 to $1 your exhaust donuts are shot. Warranty will cover them if you have warranty left. I would advise you do 'not' keep on riding your sled if the donuts are indeed "shot". You will due further damage to the exhaust 'Y' pipes (like I and many others did). If you do not have warranty left on your sled the donuts are pretty cheap and my brother was charged 1 or 1.5 hours labor to replace the donuts. A few folks on the TY site here have done the work themselves...if you do a search you can find 'how-to' instructions on how to change them yourself. It was a recent topic...you should be able to find the info here on the site. The problem you might run into is that the donuts are on backorder (or hopefully 'were' on backorder).

 

[MCApex44]

Scroll to the top of this page and you will see 'search'...click on it. Type in donuts in the key words box under Query...in the sub-section below that called search options, click on the drop down arrow for the forum and click on General Apex/Attak and you should find all the info you need.

 

[Shiek]

noise

exhaust donuts

 

[apltx08]

7500 km / ~4600 miles

Thx for the info I will check.

At 5500kms on my '08 I got the donuts on the exhaust replaced, it wasn't backfiring much but it had this ANOYING rattle at start up and it kept getting louder...don't wait to long or you'll end up wearing out your flanges on the "Y" pipes and then your talking BIG $$$... :exc:

 

[LJ 452]

Mmmmm Donuts! Glazed or plain? Yes, absolutly your donuts (exhaust that is) are shot. At least hope that's all, it could also be a cracked Y-pipe but less likely. What may have happend is that the backfire more or less was the last thing the already worn donuts could handle, poof, now you've got a small but large enough leak to cause a backfire condition. I think the constant backfire upon decel is the most common symptom of bad donuts/gaskets.

 

[cat hunter]

I have 4 new donuts if you need them and I'm in the Ottawa Valley.With all the exhaust donut problems I bought them for my Apex because it had over 6,000 miles but when I checked them they are like new.Must be the gutted muffler,NO BACKPRESSURE