T250 Exhaust 'modification'
Posted: Mon Jun 11, 2012 12:34 pm
In the midst of a deep clean/upkeep/tuneup on my 71 T250 Hustler..
Got most of the tail end and motor cleaned up and decided to attack my exhausts yesterday.
When i got the bike, i had a lot of problems with mixed gas getting all backed up in my pipes and occasionally leaking all over
the place when i was parked at the right angle.. At first my mechanic thought there was just an airleak somewhere, then after performing a compression test, ruled it a leaky inner crankcase seal. So it stayed in the shop all winter for an overhaul.
When i picked it up in the spring, it ran okay, but after a few weeks the problem came back.
This summer i managed to get the mixtures a little better, so that the right hand exhaust wasn't gooping up and the plug was still nice and toasty..
but the left hand side continued to goop up..
Which leads me to yesterday's discovery..
after pulling the baffles, i realized there was what seemed to be an extra bit of tubing floating around in the very back section of the left side pipe..
I felt around in the right side, and it wasn't there, so i got a flashlight and had a look..
Turns out there was about 16 inches of some kind of cardboard or gasket material rolled up and jammed in the rear of the exhaust, wrapping up the baffle and effectively blocking all the holes, causing it to get all mucked up with over rich exhaust.
My theory is, that for whatever reason, the baffle must have been rattling around in there, so whatever backwoods hack owned the bike at the time decided to roll up a big piece of something that inevitably became totally soaked with mixed gas exhaust.
In addition, there were a couple of bolts on that funky left side near the center of the pipe.. i pulled the rear most out, which turned out to be a 2 1/2 wood screw!! I guess the wrap bodge wasn't enough to keep the baffle in place, so some knucklehead decided to just jam a screw in there to keep it shored up.. needless to say i also found a couple little holes in the baffle where the screw tip was able to hit.
So now, everything is probably tuned wrong with the exhaust being so restricted on one side, so it's back to the drawing board with syncing and setting the pilots.
In addition, i'm left with a couple of holes in the pipe, to be filled with either jb weld (yuck), or slightly larger (prob metric!) bolts jammed in to fill them up.
Given the options, would it be worth either? Obviously i'm on the search for a new pipe (or the slim possibility of finding expansion chambers in the US!) but in the meantime, is it worth trying to fill the hole without a torch? Unfortunately, im not much of a welder.
Would filling the hole with metal putty even work given the high temperature of the exhausts once they're warmed up?
Also, anyone had 'loose baffles?' Seems weird, when i pushed it back in without the goop and extra screw, it seemed to be in there fine, i even noticed i could prob bend the notched end out a little to get it nice and snug... but why the hell would anyone have defiled those beautiful pipes without a good reason!?!
Mostly anecdotal, but any suggestions/comments are welcome..
Got most of the tail end and motor cleaned up and decided to attack my exhausts yesterday.
When i got the bike, i had a lot of problems with mixed gas getting all backed up in my pipes and occasionally leaking all over
the place when i was parked at the right angle.. At first my mechanic thought there was just an airleak somewhere, then after performing a compression test, ruled it a leaky inner crankcase seal. So it stayed in the shop all winter for an overhaul.
When i picked it up in the spring, it ran okay, but after a few weeks the problem came back.
This summer i managed to get the mixtures a little better, so that the right hand exhaust wasn't gooping up and the plug was still nice and toasty..
but the left hand side continued to goop up..
Which leads me to yesterday's discovery..
after pulling the baffles, i realized there was what seemed to be an extra bit of tubing floating around in the very back section of the left side pipe..
I felt around in the right side, and it wasn't there, so i got a flashlight and had a look..
Turns out there was about 16 inches of some kind of cardboard or gasket material rolled up and jammed in the rear of the exhaust, wrapping up the baffle and effectively blocking all the holes, causing it to get all mucked up with over rich exhaust.
My theory is, that for whatever reason, the baffle must have been rattling around in there, so whatever backwoods hack owned the bike at the time decided to roll up a big piece of something that inevitably became totally soaked with mixed gas exhaust.
In addition, there were a couple of bolts on that funky left side near the center of the pipe.. i pulled the rear most out, which turned out to be a 2 1/2 wood screw!! I guess the wrap bodge wasn't enough to keep the baffle in place, so some knucklehead decided to just jam a screw in there to keep it shored up.. needless to say i also found a couple little holes in the baffle where the screw tip was able to hit.
So now, everything is probably tuned wrong with the exhaust being so restricted on one side, so it's back to the drawing board with syncing and setting the pilots.
In addition, i'm left with a couple of holes in the pipe, to be filled with either jb weld (yuck), or slightly larger (prob metric!) bolts jammed in to fill them up.
Given the options, would it be worth either? Obviously i'm on the search for a new pipe (or the slim possibility of finding expansion chambers in the US!) but in the meantime, is it worth trying to fill the hole without a torch? Unfortunately, im not much of a welder.
Would filling the hole with metal putty even work given the high temperature of the exhausts once they're warmed up?
Also, anyone had 'loose baffles?' Seems weird, when i pushed it back in without the goop and extra screw, it seemed to be in there fine, i even noticed i could prob bend the notched end out a little to get it nice and snug... but why the hell would anyone have defiled those beautiful pipes without a good reason!?!
Mostly anecdotal, but any suggestions/comments are welcome..
Not to ask the obvious but are you sure that's not just baffle packing material coming out of the pipe? Most baffles come from the factory with a white wrapping to deaden sound. Over time it gets gummed up and you can replace or just remove it. The baffles should be held in by 1 screw on the very back of the pipe (located in that small hole in the outer pipe). Welding the other hole would be best but using a small screw would probably work too. JB weld is probably a bad idea for the reason you mentioned.
Here are the dimensions I measured, where the pipe mounts to the exhaust port:
