Swapped my engine but now having problems

[Scamceno]

I finally found the time to swap my old messed up engine out. I ordered some unknown engine on ebay, got it hooked up in a couple of hours and tested it out. I can get it to start but it only stays alive for about 30 seconds, I can't give it any throttle(not sure if the breaks at the end of my cables are preventing this? the rubber under the adjustment nuts are broken, but not the cable itself.

I could peddle it like a regular bike with the clutch pulled in(of course to start it), but after getting ready to try one more time the back tire locked up. I can't even walk the bike with the back tire down, got a nice little cut on my leg from the sudden stop(stupidly wearing shorts, but its so damn hot today). Any ideas? do I have the throttle hooked up correctly? I can only twist it a little bit as its kinda tight I noticed when I parked the bike.

Also the engine doesn't idle no matter where I adjust the idle screw, just turns off when I pull the clutch in. I'm looking around the forums and searching but everyone's problems seem to be just a tad different. Any ideas on this one?

 

[crassius]

you probably have the slide in the carb wrong, but you need to check & adjust both throttle cable & clutch cable before doing much else - if you have to, take the air filter off & watch the slide go up & down in carb & take clutch cover off & watch clutch move in & out

 

[Scamceno]

Damn I'll flip it around and see if that helps. The clutch cable moves in an out fine(seemingly at least), though the clutch cable seems off so i'll give that some more extra attention. I'll go try that momentairly, it would be nice if its something so simple.

EDIT**********

Seems my chain might be responsible for my tire locking as it just slipped off, so i'll see if putting it back on fixes it. I flipped the slide in the carb so hopefully it works when I figure out this tire situation.

As for the idling, is it the tighter the better or the looser the better? or does it vary from engine to engine?

 

[crassius]

I fail to grasp your meaning - idle is controlled by the idle screw - throttle cable should have 1/8 inch of slack so you can hear slide hit bottom.

 

[Scamceno]

EDIT

screw my luck with these things, I think I just may not be cut out for it. Its fun working on them but its been a good month of failures, I just snapped my chain, I don't know how it fell off I had it as tight as I could or so I thought. Eitherway nvm the thread, i'm outta commision for a while yet again.

 

[crassius]

a chain too tight will usually snap or pull the tensioner into the spokes and break a lot of them

 

[Scamceno]

Noted, what happend though was the chain slipped off of the sprocket and got jammed between the sprocket and the spokes. It snapped before I could stop the bike as I was cruising downhill.

 

[crassius]

your chain tensioner should be adjusted side-to-side so that it steers the chain straight onto bottom of rear sprocket - if rear sprocket is very wobbly, you might want to grind teeth to a sharp edge

 

[butre]

if your sprocket is wobbly you might want to make it not wobbly. sharpening the teeth just masks the problem

 

[crassius]

unfortunately for some folks, wobbly is the best they can do - seen them try 3 times with each worse than the last

also seen some wheels on which spoke-flex is high during turns which causes a wobble-like movement at the sprocket

no reason not to have all the help you can get from the teeth