Got problems, please help!!

[Lachiepower0402]

Hi everyone,

I have attached a photo of what happened to my motorised bicycle engine, I rode with a tight chain then the chain tensioner pushed the spokes out which jammed the wheel which in turn jammed the chain in the top of the chain case and cracked it, then i moved it to another bike and rode with a loose chain because the engine came loose because of cheap threads which then got the chain caught again in the same spot and push the cracked piece of metal out and on the ground while i was riding so i have no idea where it is, please help me, I really would like to ride my bike again.

Thank you in advance

 

[Theon]

Is that stopping you from riding?
if not, maybe you could patch it with some Epoxy, like Kneedit.

 

[Lachiepower0402]

I cant really tell if it is stopping me from riding with the motor on because my motor is very loose and i need to buy some loctite for it because the chain is loose but i am worried that is might jump out through the hole when the chain is tight and i go over a bump, also can i get epoxy or kneedit from somewhere like bunnings because i live in Australia.

Thank you in advance

 

[Lachiepower0402]

I have found Loctite no. 243, would this work with the engine mount because my bolts that screw into the engine do not hold because of the vibration of the engine.

 

[Thunderhead289]

you should have enough thread to jam nut which works really REALLY well. (two nuts on stud, tighten one down then hold the bottom one that's already tightened and tighten the second one against the bottom one AGAIN WHILE HOLDING THE BOTTOM ONE FROM TURNING) nut jamming

almost as good as gear jammin

 

[maniac57]

The hole looks to me like it won't affect anything but looks. I wouldn't bother trying to patch it myself.
As far as your loosening problem, I'd try two nuts like thunderhead suggests. I do this on all my engine mounting studs whenever there is ANY sign of loosening. Works great and is much easier to remove than loctited hardware.
As far as your tensioner problem, I tack weld mine to keep it from rotating into the spokes. Any muffler shop with a MIG can do this in seconds, usually free if you let them check out your cool bike!

 

[Going2Hell]

I have had the chain jump on my old bike like this. That damage is superficial, won't cause any problems and maybe its a new lube point for the chain! As far as the loosening, I third what Thunderhead was saying about the locknutting!

 

[Lachiepower0402]

Thank you

Thanks for advice guys, I will try and do all of the things listed, but on last question, my kit is one of the cheap ebay ones, should I use the bolts that came with it to perform lock nutting or should i go and buy some good steel ones.

 

[maniac57]

Replacing the stock studs and nuts is a good simple upgrade. Probably help your loosening problems too.

 

[Lachiepower0402]

I just released when i was tightening the back studs the right was pretty tight because i was going to go back to it, then i was doing the left one and when it was almost fully tight the right one popped and came out and i am pretty sure it runied the thread in the engine. Also the front ones are too short. Last of all when i have the motor in this position i can see that it would rub the bottom of the inside of the chain case. What the **** can i do, all of my problems are the motor mount. The engine runs and everything. This is so stupid!!!!

 

[Going2Hell]

That's rough, when my studs came out I wired the motor to the frame and twisted the wire tight. Not a good idea... the motor vibration ate my frame like chocolate and was very un-reliable.

Try a high temp epoxy,pack the hole and shove the stud back in. Maybe, and this just came to me... try drilling a hole through the side of the case and partway into the stud for a locking pin type of arrangement?

 

[maniac57]

Pictures will help us figure out your issue. Sounds to me like you have the engine mounted incorrectly or something to start with. Your chain should not be rubbing your engine!

 

[Theon]

Helicoil? That's what I'd do.

 

[Lachiepower0402]

I will probably need to add a chain tightener which i will have to weld what do you think? I will have to buy new studs because they are bent, but the main things is trying to figure out the best place to put the motor with or without a chain tensioner welded to the bike. Please help me with all of the advice you can, this is annoying me quite a lot!

 

[Going2Hell]

The stud needs either re-tapped or somehow welded, oversized bolt and force it to thread into the soft aluminum.

Definately need to remove some links from your chain, new ones stretch up to 3/4 of an inch anyway. Also a tensioner, this will stop the chain from catching because that as it sits is waaay too loose.

 

[Lachiepower0402]

I will probably remove a link but if i put the chain tensioner on and hold it the chain is very taught, but when i put it on the chain tensioner pushes into the spokes of the wheel and pulls them out of the rim, and i don't really want to weld it, but if i have to i will.

 

[maniac57]

You will have to bend the tensioner bracket to get it perfect. Most times I find they need a twist to get things right. Install it, tighten it down, THEN adjust it. I use a really big crescent wrench but whatever you use, be sure it applies the force where you want it and doesn't bend the frame rail.
After everything is perfect, then I tack weld the tensioner bracket to make it bulletproof.
You also need to be sure your rear sprocket is straight and perfectly centered. Otherwise, there will always be a loose spot in the chain from the sprocket being off center.
Get the bike off the ground and pull the sparkplug so you can easily pedal it to check chain run. Adjust as needed.

 

[Lachiepower0402]

I have mounted the engine and it sits good but it comes loose after a while from vibration but is rideable, i will be getting new high quality bolts tomorrow. I have attached a photo of the tensioner and chain, the chain sometimes comes of the tensioner i suspect because of the wheel not being true or sprocket. The tensioner does not move anymore so should i weld it anyway?

Thank you,
Lachlan Fullagar

 

[maniac57]

Do not weld it until yu get it perfect. Take the time to find the problem or you will never have a reliable ride. The chainline is one of, if not THE, most important parts of a good motorbicycle. Search ''ragjoint installation'' for more tips on getting the chain right.
TONS of helpful info is just a search away.

 

[Theon]

I use three pieces of paddle pop stick to center the sprocket when installing the rag joint.
If you still have dodgy thread problems, Helicoil, or you could try Epoxying the better studs in.