This is a serious problem

H

Hzryder

New Member
So I recently rebuilt my top end and it runs perfect it has plenty of oil and everything else is fine but when I ride anywhere from 100 to 200 feet it acts like it’s about to lock up (it actually does sometimes) then It randomly works again for another 5 minutes I don’t pin it I don’t beat it I simply try to cruise it but it just try’s to lock up and it runs beautifully when I first start it then it starts ticking and it runs nice with idle but the ticking is really loud but when I ride it there’s no tick until it try’s to lock up I keep pulling off the jug and everything is fine there’s a normal amount of play in the crank and It spins fine nothing has ever fallen into the crank my gears are fine and the bearings are fine so what the **** is causing this
 
I think Jerry has it right. If it only ticks and tries to lock up when you are moving and the engine idles ok then it’s likely unrelated to the top end rebuild. Hope you find the problem and tell us what it was. I would probably get it started and get the back wheel off the ground and watch what is going on when it’s clicking.
 
The chain is well lubed and perfect slack and the bike has double kickstand so the wheel hovers over the ground it spins fine it’s definitely not the wheel that’s ticking if I have it running at idle and I give it a rev or two it starts ticking it’s a 1 peice Jug and I’m just really confused also there isn’t any play or wobble in the wheel I’ve had it rebuilt with plenty of grease and the wheels only about maybe 1 month old also I forgot to mention the loss of power before it tries to lock up and the fact it kills immediately when I pull in the clutch
 
Then I would look closely to see if you have a crack in the cylinder. Lots of times people mistake a blown head gasket for a mechanical click. I know you don’t have a head gasket but a crack will have the same effect.
 
Right as there out of stock well that’s just my luck thank you for the help also if I can’t find the crack or if there’s isn’t even one what should I do
 
The sad thing is I have the 100cc not the yd100 the bt100 and you can find jack squat for these motors I got lucky being able to buy a rebuild kit from Australia and had it freight shipped to me I’ve looked for a two piece design and no luck
 
Are you sure the engine is actually 'locking up'???? (or is the engine slowly losing power until it simply turns off)?

Could it be that the fuel isn't flowing to the carb fast enough? (gas cap not venting)?
Could the spark plug be fouling with oil from simply 'cruising' & not getting hot enough to burn clean ?? (too much oil in gas)?
 
Update: so I took the top end off and when I pull the piston rod and roll the crank in the case every turn it makes a little knock but stops when I pull it faster the cylinders fine I have a boatload of pistons the compression is strangely high I haven’t started it to see if it still knocks because I don’t have a carb but I have checks the rim that’s all good the case bearings are good the clutch is fine so I’m at a loss
 
And yes I’m absolutely sure it’s locking up because it loses all throttle and bogs then it’ll work for a second then you’ll feel like your holding the coaster brake trying to give it throttle then I pull in the clutch it dies then I’ll be rolling let the clutch out and it’ll start again
 
I think your gas tank isn't venting properly
When a engine 'locks up', it stays locked up (& won't re-start)

Another thing you might check... make sure your choke lever is down.
 
Locks up to the point where the back wheel won’t move when I try to see if there’s compression and it’s tight but it still manages to free up
 
I still think your problem is something other than the engine locking up...
I'm sure if you can find someone in your area with experience in these bikes; they can quickly find your problem for you.... good luck!
 
Hzryder said:
Update: so I took the top end off and when I pull the piston rod and roll the crank in the case every turn it makes a little knock but stops when I pull it faster the cylinders fine I have a boatload of pistons the compression is strangely high I haven’t started it to see if it still knocks because I don’t have a carb but I have checks the rim that’s all good the case bearings are good the clutch is fine so I’m at a loss
Click to expand...
 
Have you taken a real close look at the gear reduction on the right side? Since you had to do a rebuild on the top end I assume you have quite a few miles on it.
 
You must log in or register to reply here.
Back
Top