I need help please. Chain Tensioner...

mlrosier

New Member
Jul 29, 2008
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0
I just got this put together after receiving it on Friday of last week....

NEW BLACK 80cc Motor Bicycle Engine Kit Bike Gas Kits - eBay (item 260260143153 end time Jul-17-08 23:03:31 PDT)

After stripping a total of 3 bolts, it's finally all together. Can definitely tell it was made in China. Anyways, the chain idler won't stay put, and it keeps causing the chain to get thrown off of the gears. I start pedaling, let go of the clutch, and it acts like it wants to start, but I never get far enough because the chain idler moves and offsets the chain, throwing the chain off of the gears.
I don't even know how to work the choke on this thing, the lettering is in chinese, so I don't know which direction is full choke, and which is off choke. Can anyone help? I'm half tempted just to throw the whole thing away and go buy a moped.

Also, the clutch is very hard to pull in. It takes a great deal of strength to pull the lever in enough to push the locking pin down.

Thank you.
 

Ilikeabikea

Active Member
Jan 27, 2008
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Ptown, Texas
Welcome to the forum. Sorry about your problems. Lots of people drill through the idler into the frame and put a self tapping screw into it to keep it from moving around...............................
 

jasonh

New Member
Jun 23, 2008
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Longmont, CO
Full choke is up, choke off is down.

For the clutch, you may need to shorten the outer cable so you don't have any tight curves in it. Also try lubing the clutch cable.

For the tensioner...they suck. You can ditch the tensioner altogether and just shorten the chain and adjust your rear wheel to take up slack. Or, you could do something like this:

http://motorbicycling.com/f30/motorized-bicycle-spring-loaded-chain-tensioner-1128.html
 

Saddletramp1200

Custom MB Buiilder
May 7, 2008
1,446
54
48
Houston, Texas
Welcome! If you do drill the tensioner drill only one side of the tube. That part of the frame carrys a lot of weight! I would not drill the tube at all. Take the bike Minus the rear wheel to a welding shop and let them see what you want to do. A simple piece of steel can be welded to the frame to force the idler to stay put. Either on top or bottom of the frame.
 

mlrosier

New Member
Jul 29, 2008
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Wow. Thank you all very much for the replies. I am very grateful. I will probably go the route of removing links and not using the tensioner at all. That seems like it would be the best way to go. And thank you for the advice on the clutch cable. I will give all of this a shot and see what it does. :D Thank you. :D
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
Just be aware that the china chains stretch a lot sometimes and you'll either need to remove another link, or find some kind of tensioner.
 

Saddletramp1200

Custom MB Buiilder
May 7, 2008
1,446
54
48
Houston, Texas
Got me thinking about those chains. I had a "fryed rice" chain kiss the back of my left leg a few years back. Still have the scar. If you can, get rid of that stock chain ASAP. A 415 is what I use. Most of the time they just slide off the sprockets. Sometimes they don't.
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
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north carolina
Shorten your chain on the motor side. Adjust your wheel for it. If the pedal side chain has slack use the tensioner there. It was what finally cured my chain problems.
 

misteright1_99

New Member
Mar 21, 2008
716
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Treasure Coast, Florida
I also would suggest the tensioner, as well as the #41 chain, sooo much better than the stock parts...And what I did for the clutch is to just lengthen the clutch arm and turn it inwards for a more direct pull, as well as replace the junk stock cable and clutch lever....
 

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Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
On my latest build, I'm running a BGfast no-bearing tensioner roller just to see how it work out...call me sick that way.

My skate wheel tensioner didn't pan out because the wheel is too worn and rounded at the shoulders. Maybe a new, flat one would be better.
 

ebmvegan

New Member
Jul 15, 2008
283
0
0
OC, Ca
On my latest build, I'm running a BGfast no-bearing tensioner roller just to see how it work out...call me sick that way.

My skate wheel tensioner didn't pan out because the wheel is too worn and rounded at the shoulders. Maybe a new, flat one would be better.
Have you tried grinding a groove down the middle? I'm not sure if the wheel would become too brittle, but it's just a guess.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
I will try that with the skate wheels I have. For now, I am running the stock tensioner just to see how it goes....