blackONblack
Junior Member
Ok, first the symptoms:
I rode my bike to work on Friday. In the morning, I didn't notice a problem at all. On the way home, I started to notice a smell--I didn't think much of it, I figured it was a car in front of me burning something. I had previously had a coolant burning problem with a previous car, and so I recognized it as probably being coolant.
This morning, I got up and went for a ride. I was taking it for an oil change (I don't know if I'll take flack for this on this board, but I live in an apartment with an underground garage, not good conditions for changing my own oil), and I noticed the smell was still there. Immediately after the oil change, it was a really strong smell, and this time I looked down to see a decent amount of smoke coming from the bottom of the engine area.
I pulled off to take a look, and I couldn't see anything dripping, but I could tell there was smoke coming off the two pipes that (I think) funnel back into the mufflers. After some time running, the amount of smoke decreased but was still there. On the ride home, I couldn't see the smoke but at every stop light I could still smell it.
Now, some possible external factors/causes:
Temperature: This is the first week of the season where the temperature dropped below 50. On Friday, coming home, the actual starting temperature of the bike was probably lower than on my way to work, as the underground garage I keep my bike in is warmer than the covered spot I had at work (no sun, plus a high temp of about 60 degrees that day). Could the temperature be affecting some fittings that aren't expanding at the same rate, and causing a leak? I don't know if this is possible since the bike was for sure warmed up after the long rides to/from work and the bike shop.
Engine braking: I don't usually downshift to slow down, but I almost always will let off the gas sharply when I see traffic/stop lights/etc. ahead, in order to slow down before I get on the brakes. On the way out of my work parking lot, while the bike was still pretty cold, I did this in 1st/2nd gear quite a bit. During one sharp let-off, I heard a crunching sound. At the time I figured it was debris hitting some plastic or a leaf crunching under the tire. After further thought I wonder if it is related to the smoke. Could I have put too much strain on the top end/gaskets while cold? Did I bust something in the valvetrain? Something else?
Oil change: My first thought in seeing the smoke was that some extra residue from the oil change was burning off. When it continued on my way home, and I remembered the smell from the previous day, I can almost 100% rule this out. This still leaves the possibility that whatever might be loose/broken was made worse by some careless tech, but I don't think it is the original cause. Just thought I'd include this so you all know I considered it as an option.
Something else: I come from an engineering background and did some minor work on my old bike, but I am very very far from being a mechanic OR a true gearhead! It's likely that I have no idea what i'm talking about and need your help!
So, anything you all can come up with would be a VERY big help, and I'd appreciate it a whole lot. Thanks in advance!
I rode my bike to work on Friday. In the morning, I didn't notice a problem at all. On the way home, I started to notice a smell--I didn't think much of it, I figured it was a car in front of me burning something. I had previously had a coolant burning problem with a previous car, and so I recognized it as probably being coolant.
This morning, I got up and went for a ride. I was taking it for an oil change (I don't know if I'll take flack for this on this board, but I live in an apartment with an underground garage, not good conditions for changing my own oil), and I noticed the smell was still there. Immediately after the oil change, it was a really strong smell, and this time I looked down to see a decent amount of smoke coming from the bottom of the engine area.
I pulled off to take a look, and I couldn't see anything dripping, but I could tell there was smoke coming off the two pipes that (I think) funnel back into the mufflers. After some time running, the amount of smoke decreased but was still there. On the ride home, I couldn't see the smoke but at every stop light I could still smell it.
Now, some possible external factors/causes:
Temperature: This is the first week of the season where the temperature dropped below 50. On Friday, coming home, the actual starting temperature of the bike was probably lower than on my way to work, as the underground garage I keep my bike in is warmer than the covered spot I had at work (no sun, plus a high temp of about 60 degrees that day). Could the temperature be affecting some fittings that aren't expanding at the same rate, and causing a leak? I don't know if this is possible since the bike was for sure warmed up after the long rides to/from work and the bike shop.
Engine braking: I don't usually downshift to slow down, but I almost always will let off the gas sharply when I see traffic/stop lights/etc. ahead, in order to slow down before I get on the brakes. On the way out of my work parking lot, while the bike was still pretty cold, I did this in 1st/2nd gear quite a bit. During one sharp let-off, I heard a crunching sound. At the time I figured it was debris hitting some plastic or a leaf crunching under the tire. After further thought I wonder if it is related to the smoke. Could I have put too much strain on the top end/gaskets while cold? Did I bust something in the valvetrain? Something else?
Oil change: My first thought in seeing the smoke was that some extra residue from the oil change was burning off. When it continued on my way home, and I remembered the smell from the previous day, I can almost 100% rule this out. This still leaves the possibility that whatever might be loose/broken was made worse by some careless tech, but I don't think it is the original cause. Just thought I'd include this so you all know I considered it as an option.
Something else: I come from an engineering background and did some minor work on my old bike, but I am very very far from being a mechanic OR a true gearhead! It's likely that I have no idea what i'm talking about and need your help!
So, anything you all can come up with would be a VERY big help, and I'd appreciate it a whole lot. Thanks in advance!