Apex Backfiring *Update 12-06-06*

[mdkuni]

My sled started backfiring this weekend. It happens when I am at about the 7,000RPM range and up and then let off the throttle completely or enough to let the RPM's drop quick. The higher the RPM's before I let off the throttle the bigger the backfire.

My sled is completely stock except for the big boy rear spring. The sled has around 3,700 miles on it.

This weekend is when it started. The only thing I did to the sled this weekend was install a bigger fuse for the accessory outlet, changed the chain case oil, and adjusted the headlight aim.

I tested the TORS when I was stopped by holding the throttle. The lights immediately kicked on the display and the TORS was activated. I did not disable it though as I do not know how to...

Anyone have any ideas?

 

[welterracer]

You have 6700 miles on a APEX?????????? could be a bad plug... or a burned valve.. with that kind of mileage..

 

[mdkuni]

TYPO! It was supposed to read 3,700. I changed the original post.

 

[welterracer]

Bad spark plug

Arking plug boot.. bad coil..

Take it to the dealer

 

[mdkuni]

Well, if it is just a plug, which would be nice, as I will just replace the plugs and see what happens. I really do not want to take it to the dealer, but if new plugs do not fix it I will have to.

Is it normal for plugs to go this early on a 4-stroke?

 

[welterracer]

A spark plug could go at any time.. so could a coil..

they are electonic parts used in very harsh conditons

 

[bgbytoys]

happened to me this weekend and it was also the first time i put alcohol in with the gas. it was thew alcohol for me. stopped using it and the popping went away.

 

[youngster66]

backfire.

Had the same problem with an 05 RX1. Found to be a faulty throttle safety switch located inside the throttle on the Bars. Just disconnect to see if problem subsides. If it does then replace your switch. These are very common in failing.

 

[Reaper]

Mine does it after a long wide open pull across the lake. When you back off it pops several times as you are coasting to a stop.

 

[mdkuni]

Re: backfire.

Had the same problem with an 05 RX1. Found to be a faulty throttle safety switch located inside the throttle on the Bars. Just disconnect to see if problem subsides. If it does then replace your switch. These are very common in failing.

Throttle safety switch? What does it do, and is there an easy way to locate it?

 

[Apex_GT]

The cool thing I've seen is when your wide open and let off the gas real quick a lil fire ball comes out of the exaust...Anyone else see the Flames?? Its really cool...

 

[Reaper]

Yes, I guy I was riding with said it was like a flame thrower so I would suspect it is going rich.

 

[impalapower]

Mine does it after a long wide open pull across the lake. When you back off it pops several times as you are coasting to a stop.

You guys saw mine do it this weekend. Terry said it was common. I didn't hear any pops, just told that there was flames.

 

[SledderSteve]

Re: backfire.

Throttle safety switch? What does it do, and is there an easy way to locate it?

That would be the TORS you described checking in your first post. The instructions to bypass the TORS are found in the troubleshooting section of your owner's manual, page 9-1 for the Apex ER.

If it is in fact the TORS causing your backfiring it will likely be due to the throttle cable being out of adjustment.

 

[suprfst]

My 05 started doing the same thing a few weeks ago,right about the time I turned my idle down to 1000 rpms to get more engine braking effect.