L
likearock111
Guest
Hey MBers,
I just wanted to put a little note up here regarding my own difficulties with my 70cc 2-stroke, so maybe other people can learn from my mistakes. Always Always ALWAYS check your bolts for tightness after every ride. I used to be in the habit of checking them every 8-10 rides or so (most of mine are short, ~5 mile joyrides). Not only was this bad for performance, it was also probably pretty unsafe. Well, I've changed my ways.
A while back, my engine started having the typical "bogging" symptom after a certain amount of time spent at WOT. The threads on here pointed me toward checking the carb and checking for air leaks. So, I took apart the carb, cleaned it, rebuilt it, replaced the black rubber o-ring I had installed between the intake manifold and the carb, and sealed it all up extra tight. I also replaced the intake and exhaust gaskets.
None of this worked. And, on top of everything, it started leaking black semi-burnt fuel/oil. In the process of trying to figure out where the heck the black stuff was leaking from, I discovered that one of the bottom 4mm bolts that holds on the left-side front cover had completely fallen out, and the other three bolts were pretty loose. I don't know what you call this cover, but it's just in front of the cover that goes over the drive gear. So, long story short, I replaced the missing bolt, LocTited all of the main bolts on the engine, and now my engine runs better than ever!
So, moral of the story: check your bolts! It might save you some frustration, money, or even some road rash.
-Rock
PS: Mods, this may go better in the 2-stroke section, since it has to do with HT performance. I was just thinking that tightening bolts is more generally applicable than just 2-strokes. Either way.
I just wanted to put a little note up here regarding my own difficulties with my 70cc 2-stroke, so maybe other people can learn from my mistakes. Always Always ALWAYS check your bolts for tightness after every ride. I used to be in the habit of checking them every 8-10 rides or so (most of mine are short, ~5 mile joyrides). Not only was this bad for performance, it was also probably pretty unsafe. Well, I've changed my ways.
A while back, my engine started having the typical "bogging" symptom after a certain amount of time spent at WOT. The threads on here pointed me toward checking the carb and checking for air leaks. So, I took apart the carb, cleaned it, rebuilt it, replaced the black rubber o-ring I had installed between the intake manifold and the carb, and sealed it all up extra tight. I also replaced the intake and exhaust gaskets.
None of this worked. And, on top of everything, it started leaking black semi-burnt fuel/oil. In the process of trying to figure out where the heck the black stuff was leaking from, I discovered that one of the bottom 4mm bolts that holds on the left-side front cover had completely fallen out, and the other three bolts were pretty loose. I don't know what you call this cover, but it's just in front of the cover that goes over the drive gear. So, long story short, I replaced the missing bolt, LocTited all of the main bolts on the engine, and now my engine runs better than ever!
So, moral of the story: check your bolts! It might save you some frustration, money, or even some road rash.
-Rock
PS: Mods, this may go better in the 2-stroke section, since it has to do with HT performance. I was just thinking that tightening bolts is more generally applicable than just 2-strokes. Either way.
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Must've been a hairline crack there, or something. At least it didn't take too much effort to fish the threaded portion out of the hole, though. Now I need to try to hunt down a 10mm, 1.0 thread pitch fuel petcock before this weekend.
