Originally Posted by wtwrestling07
I just built my first motorized bicycle, so i thought i would join this forum. I bought a Huffy Cranbrook on sale for $88.00 at walmart and bought a 80cc (66cc) Bicycle engine kit off of ebay for $145.00 with free shipping. I got my kit in the mail friday and had it all put together in a few hours except for sizeing the chain and drilling the handle bars. I had to go out the next day and buy a used drill and a punch for $5.00 to finish the project. I got it all put together by saturday morning and took it outside to test it out. At first I was having some trouble with the clutch arm then I got it working. Fired it up and it was running good. Rode it around the parking lot a few time then shut it off to let it cool down. Fired it up again and rode it around a few more time and it was still running good. After I tried to fire it up a third time the chain poped off and got stuck in the sprocket, so I had to go and get a screw driver and dig it out and put it back together. Well after about 3 or 4 more time of digging the chain out of the sprocket, I noticed I stripped the top bolt of the chain tensioner, so I went to lowes the next day to go buy some new heavy duty ones for it. After I got those put on, the chain is still poping off. I also noticed after the chain poped off so many times it messed up my back tire allignment so I had to straighten it back out. Still the chain is poping off. The only other thing I can think of is the front motor mount is not completely straight and kind of leans to the left a little b/c the large diamiter down tube bracket that was in the kit dosnt fit right. One side of the U bolt is hiting the engine so i cant tighten it down the way it should be without grinding half the threads off and i dont have a grinder. Its only off by a hair or so. Even with the engine mount the way it is i dont think it should be jerking the chain off the way it is. So with all this said, I am wondering has any one else ran into a problem like this or is there somthing I am missing or not seeing? I have read alot about using the kit as a daily driver and them being somewhat reliable so I know somthing isnt right. I am going to try to upload some pictures of the bike and the front mount and chain tensioner so you can see what im talking about. I am also thinking about buying a Large Universal Front Engine Mount from SickBikeParts.com to fix the mount problem, I just dont know if that is gona fix the chain problem.
problem I see is the way you have the rear on that engine mounted, the front mount sitting like it is is gonna be a problem also, the engine needs to be securely mou ted to the frame and your is t done like it is, I have a Huffy build I did back in 2010, one of my best riding bikes, in order to get the engine mou ted like it needed to be I removed the chain guard and put a slightly smaller sprocket on the cranks, a 36T works great, lets the engine settle in lower in the frame and will likely cure the misalignment issue you are having if you will saddle the rear of the engine on the frame like it should be and then order you a large frame front mount from www.sickbikeparts.com
, if I wasnt at work on my phone Id post links to the stuff here but it aint hard to find.
getting the engine mountex correctly and securely is the most important part of a build.