Chain problems

[bob geo kart]

Hello, I just got my build done. New torque converter, new axle sprocket, and new chain. I'm using the honda clone with a straight pipe and a vm22 mikuni. The problem is the chain won't stay on. I drove it like 10 feet and it pops off. it also makes a little clunk like its slipping. Here's a couple pics of the chain.

 

[karl]

Judging by the cut off metal plates, and inch tall stack of washers,
your frame or motor mount is bending when you hit the gas.

Is this on a hacked up lawnmower chassis? Probally needs a bit of reinforcement.

 

[bob geo kart]

i saw the that but i didnt it think that would be it. no its a cater mini talon that used a vertical engine. so i converted it to use horizontal engine. ill just stiffen it up and also the shocks on the back move a little that makes the whole swingarm thing move up and down. Do you think that could be a problem to or it it supposed to do that

 

[Denny]

Check chain alignment also. Engine may have a twist to it also. Is the engine hitting anywhere on the frame and seat when the rear suspension is in compression?

 

[bob geo kart]

chain alignment is good also the engine straight. no the engine doesnt hit the frame. i think the sprocket bent or some with it bc it s a sprocket and hub not just a sprocket with a welded hub. The reason i think that is the chain will get tight then lose then tight again as the chain goes around. I also need to stiffen the motor bc there's a little bend in it.

 

[madprofessor]

Can't really tell, but that axle doesn't look like it's a 1" axle. If that's a 3/4" axle, you can bet it's flexing when you give it the throttle.

 

[bob geo kart]

Ya its a 3/4. Look at this every 1/4 axle rotation the sprockets do that so is it bent sprocket or the way its on the hub. (I did have the other bolts in while driving)

 

[bob geo kart]

I think I found the problem, Engine is crooked.

 

[madprofessor]

Motor mounted out of square to the frame does mean misalignment, which means chain walking off the sprocket as it rotates. Same way you'd try to take the chain off by pulling it to one side and slowly rotating the sprocket.
Apologies for negativity here, but that homeowner-grade rafter square is for purposes other than machining and millwrighting. It's not long enough or true enough and for many applications not compact enough.
Get a REAL straight-edge, metal or metal-edged not to warp or bend out of true, that will bridge across the entire width of that axle sprocket and still reach all the way across the other sprocket.
I've used a 1" wide aluminum yardstick all my life to align pulleys, sprockets, bearings, etc...... Floppies itself into tight spaces, then becomes a dead true edge when turned on its side. Angle iron and similar can't be depended on to be true straight.

 

[bob geo kart]

Ok. I used a metal one but it would reach. I thought the same thing. Would a metal level or a metal t square work to align the sprokets. I looked at the motor plate and it's crooked and bent. I'll will have to re weld it and put a brace under it.

 

[madprofessor]

Any very stiff item like a level or t-square or metal framing square would be great. What really counts is you knowing in your heart that your piece being used is perfectly straight on one edge that cannot be bent or skewed differently.
If you stretch a string tight along an edge of something like you were about to snap a chalk line, you can see for sure if that edge is straight. As long as that edge will stay perfectly stiff, and you can lay it flat all the way across the big sprocket, you have your alignment tool.
First it will tell you if your sprocket itself is still flat. As long as it is, it will then also lay flat across the other sprocket if they're aligned. If not, that's what needs fixing.
Crooked plate: If your motor bolts slop around in the slots a little like mine do, you might be able to twist the motor enough to get away with the plate as is, a little crooked or not.

 

[bob geo kart]

Ya mine moves but not enough and I don't fill like drilling it out to make it move more. Sprokets looks good. I will definitely use a level or t square to square it. Thanks for the help.

 

[Denny]

Glad you found it.

 

[Denny]

You may want to upgrade the axle to 1”. That 3/4” is probably flexing like a wet noodle under stress. Now would be the time to do it.