Hey. Im new to this site and I really like how it is set-up. I am having major problems with my motorized bicycle. I purchased it about a week or two ago from a gentleman on Craigslist. It ran fine and started up perfectly. Everything seemed to be working fine until I took it on a long ride. On my way back to my home, I was going up a slight hill and I slowed down at the top. When I attempted to cross the road the bike stalled and then when I tried to start it back up, I had no sucsess. It did not make any noise as if it was attempting to start. I tried numerous time but still nothing. Then, I decided to just pedal home. Once home I tried to replace the spark plug. After doing that I tried to run it again. Still nothing. I kept trying and then it jumped into life. I rode it around the block a few times then on my way back it died again. I went through the same series of events as the time before. Replaced the plug, tried numerous time to start it and then it started. But this time when it got running, there was a loud clanking noise emitting from somewhere. It sounded like metal on metal. I talked to my father and he didnt know what was wrong. I looked around on the internet and many people talk about a disconnected connecting rod or a loose piston or drive shaft. Can anyone help me? If it helps I have a 2-stroke 68.5 cc engine on a Huffy Cranbrook. Thanks!
Motorized Bike Engine Trouble
- Thread starter Jaryd
- Start date
First there is not all that bad news, and bad news. Not all that bad news is that maybe the wrist pin bearing that connects the piston to the rod is bad, maybe the connecting rod bearing or either two of the crankshaft bearings are bad, that is assuming it is in the engine itself (that's about all the parts that are in there) the , and not the clutch or other parts. Can't tell until you or someone gets into the engine. Now for the bad news, it can be done, many people who are mechanically inclined can go into a engine and come out running, but my assessment is that neither you or your dad don't fall into that category. My crystal ball tells me a replacement engine is in order.
See what is involved.......
Chinese HT breakdown pictures by Ron-Becker - Photobucket
Where the arrow is that is where the crankshaft bearings are located..one on each side. The wrist pin bearings are in the connecting rod..sticking out to the right and the connecting rod bearings are hidden in the crankshaft (inside the two round parts). To install the rod bearing the crankshaft has to be split in two..see the bolts (three of them)
If I was you, I'd tear it down so you can see what is inside, and have a better understanding how these engines are put together...you will never learn without getting your hands dirty. These engines are by far the easiest engines to work on..so little parts.
See what is involved.......
Chinese HT breakdown pictures by Ron-Becker - Photobucket
Where the arrow is that is where the crankshaft bearings are located..one on each side. The wrist pin bearings are in the connecting rod..sticking out to the right and the connecting rod bearings are hidden in the crankshaft (inside the two round parts). To install the rod bearing the crankshaft has to be split in two..see the bolts (three of them)
If I was you, I'd tear it down so you can see what is inside, and have a better understanding how these engines are put together...you will never learn without getting your hands dirty. These engines are by far the easiest engines to work on..so little parts.
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