Honda VTX 1300 / VTX 1800 Motorcycles Forum banner

VTX Backfiring

12K views 8 replies 6 participants last post by  Biddy 
#1 ·
Ive got a vtx 1300 c that I got in August of last year, it now has started backfiring when I let off of it. They told me at the dealer it was a block off plate so I got one on the way. It has a dyno jet kit and vance and hines pipes, I took them off is there supposed to be a gasket other than the steel plates attached to the pipes. Im new to this any help would be appreciated. I also ordered felpro 60569 gaskets to put back on but I have no idea what the block off plates are they said they went on the head between the exhaust. Some kind of smog control.
 
#2 ·
The block off plates are for what's called the PAIR valve system, a pollution control that injects air into the exhaust. The plates replace the stock plates with hoses that sit atop each cylinder. You won't have to touch your pipes. There are several detailed write-ups, one of them at vtx garage.
You can also find several threads here.
Just do a search for PAIR VALVE removal.

You can get the plates at directLine parts, or Sherm's. Sometines, they are referred to as 'coasters'.
Removing the whole system is fairly simple, and will take about an hour, including taking the tank off.
Keep us posted if you need further help or info.
P
 
#3 ·
+1 ^

And, if there is ANY leak whatsoever between the head and the exhaust, you will get popping on decel. Make sure you get those gaskets on there ASAP, before you start messing with the carb.

Let us know what you find......
 
#4 ·
Any mods to the air box and/or filter? Too much air will cause backfire on decel.
 
#5 ·
Vtx Backfiring

Thanks guys, im gonna put the gaskets on first thing tommorrow when they get here, there looked to be some black exhaust residue around the head so I hope that fixes it. Apparently whoever put on the pipes didnt feel it needed exhaust gaskets. If that dont fix it im gonna do the pair valve removal, should I get the black or steel block off plates from direct line parts. Also, I looked at some other threads and should I not be running 93 octane some people said it would cause backfiring to go with the cheap stuff.
 
#8 ·
If there's no crush gaskets between the pipe and head, that's more than likely the major cause. After you install them and fire it up, ride it about 15 min to get them hot, then go back and recheck/tighten the nuts.
P
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top