mike1958
Newbie
I have a 2007 Apex with just over 1000 miles. Recently when I started the sled it had a more 'throaty' sound to it. It has also started to backfire occasionally, particularly when I accelerate hard, then release the throttle. Any ideas what might be causing the problem?
Thanks
Mike
Thanks
Mike
harm67
Extreme
sounds like you ate up your dougnuts 
exhaust
yeaup. Im sure your exhaust donuts are gone for a crap. Get them fixed as soon as posible so you dont damage your y pipes.
yeaup. Im sure your exhaust donuts are gone for a crap. Get them fixed as soon as posible so you dont damage your y pipes.
06apexrtx
Expert
its a common issue from what ive read over the last 2 years.
schmeg
Expert
Donuts or a crack in a headpipe/y-pipe.
ApexRtxGuy
Expert
change exhaust donuts asap to prevent header pipe crack.
apltx08
TY 4 Stroke God
Here's how to do what I call the RAG test, start her up and let it idle then use rags any type and go to the rear of the sled while its still idling and PLUG both exhaust to the point of stalling...if you have plenty of back pressure and tends to stall everything is good!...if she DOESN'T and you cant get her to stall and hear some leakage going on in the tunnel or under tank area check for cracks in the exhaust & header junction, noise under gas tank your due for a DONUT job!!! its quick and easy and won't harm anything, for best result try doing it when motor is cold.
mike1958
Newbie
The donuts do seem to be the pick. I'll have a look at them soon. Any solutions to prolong their life in the future, as mentioned, I have less than 1000 miles on the sled. Thanks
harm67
Extreme
They are a consumable part. Some last longer than others. I think the trick is to make sure you have agood tight fit there. Some have even gone to hi temp silicone to ensure a leak proof fit. Check this out... 
http://www.ty4stroke.com/viewtopic.php? ... highlight=
http://www.ty4stroke.com/viewtopic.php? ... highlight=
did you buy the sled new or used,i can't believe the donuts are bad already with the low miles you have.i find the harder you push the sled-whoops,ruff trails,lots of lake blasting wfo,or drag racing lots it happens more often.i know guys that just "cadillac" down trails=take it easy,with over 6000mi-no issues.its just a crappy deal.just changed my header with a bender racing product-cracked my header 1in past the donuts i just replaced.titanium is light,but its not all that great,bender racing is stainless=no more issues,but i don't wanna scare you, its probley your donuts.good luck.mike1958 said:
mike1958
Newbie
I'm surprised too. I bought the sled new in the states (I'm from Canada). Needless to say, no warranty. I am in the process of pulling the Y joints apart and the two that I am looking at don't look terribly bad. Since I have it apart, I will replace them anyway. Maybe one of the other two will show some wear.
I do ride the sled fairly hard. I'm an old guy (50), but none of the kids that I ride with are ever waiting for me.
I do ride the sled fairly hard. I'm an old guy (50), but none of the kids that I ride with are ever waiting for me.
zoomzoom
Extreme
mike1958 said:
Had the same problem on my 2007 with about 1000 miles and the exhaust donuts was NOT my problem. Look up my posts under "Need a Fix" forum to see how I fixed it. It was all spark management!
mike1958
Newbie
Too bad I didn't see your solution sooner. I just checked all my donuts and the Y and everything looks new. I'll put it back together, then check for arcing.
zoomzoom
Extreme
You have to check it in a completely dark room or you'll never see it. Go ahead and pull dust boots off. and reconnect coils. Also, the troaty sound you talk of, have you removed the airbox anytime before this started to happen. One thing I've noticed is that sometimes the intake boots don't seat properly which could also cause a more "throaty" sound. It is also possible that if you or someone else replaced plugs that you could have spark loss and airbox not properly replaced.
I know it sounds far fetched but it's really not. Anyone who's dealt with this airbox know what I'm talking about.
I know it sounds far fetched but it's really not. Anyone who's dealt with this airbox know what I'm talking about.
mike1958
Newbie
Checking the air box was the first thing I checked. I made sure that the boots were seated properly. The spark plugs haven't been touched. Other than the sound and the backfire, the sled runs as good as ever.
