ok, so my kids bike has been stumbling and no one on the mini forum seems to have any help..
I tried jetting bigger and smaller as well as swapping to a 26mm carb and v force reeds so it's not fuel related at all imo.
I changed out plugs with a spare used plug I had (next step for plugs would be a new one)
I checked the trans gears all are good I even changed a few anyway and an outter bearing with newer ones from another LT80 trans I had laying around..
compression is 115psi I DID mil the head so I suppose that's a little low for a motor with a milled head but LT80 (Jack Moore) didn't have anything to say about the compression.. so I assume it's ok.
I recently changed a crank bearing and seal only on one side (had to cut that one off in pieces already so gave up on the other side) and I suppose it hasn't run good since.
I caught a slight leak on the head gasket but I put in a new one and didn't help. I'm going to order a full top end gasket set and pull the top end off and inspect it as well as the base gasket.
I had a leak previously in the crank seal so I checked both and they were good. I checked the block and it doesn't look to be leaking.
I checked the stator and it checked out.
it ONLY does it under load. when I sit the rear of the bike off the ground it revs up to top rpms clean...
then I jump on the bike and go to ride it and it does it again. it will get up to speed but it keeps hitting a dead spot on rotation it seems like... I watched when it was off the ground and didn't notice axle being bent or anything. the entire bike jerks kinda like when I watch the pivot point (motor is the swing arm) the front mount goes slack then lifts again. it's really hard to watch it while riding but I mean I CAN if I try hard and not really watch where I'm going, mind you I do this testing in the street in front of my house with no helmet so it's not exactly my ideal way of testing this pos... I'm about pissed I've been playing with it for days chasing my tail... fricken shop is closed today/tomorrow so tuesday would be the soonest I could get a new plug... I want to play with the CDI even change it out and see but to me that doesn't seem like something load affected..
any help would be greatly appreciated! I'm stumped and tried almost everything besides pulling the top end and cracking the block again... I'm tempted to let my kid just ride it until it goes down all the way.
I tried jetting bigger and smaller as well as swapping to a 26mm carb and v force reeds so it's not fuel related at all imo.
I changed out plugs with a spare used plug I had (next step for plugs would be a new one)
I checked the trans gears all are good I even changed a few anyway and an outter bearing with newer ones from another LT80 trans I had laying around..
compression is 115psi I DID mil the head so I suppose that's a little low for a motor with a milled head but LT80 (Jack Moore) didn't have anything to say about the compression.. so I assume it's ok.
I recently changed a crank bearing and seal only on one side (had to cut that one off in pieces already so gave up on the other side) and I suppose it hasn't run good since.
I caught a slight leak on the head gasket but I put in a new one and didn't help. I'm going to order a full top end gasket set and pull the top end off and inspect it as well as the base gasket.
I had a leak previously in the crank seal so I checked both and they were good. I checked the block and it doesn't look to be leaking.
I checked the stator and it checked out.
it ONLY does it under load. when I sit the rear of the bike off the ground it revs up to top rpms clean...
then I jump on the bike and go to ride it and it does it again. it will get up to speed but it keeps hitting a dead spot on rotation it seems like... I watched when it was off the ground and didn't notice axle being bent or anything. the entire bike jerks kinda like when I watch the pivot point (motor is the swing arm) the front mount goes slack then lifts again. it's really hard to watch it while riding but I mean I CAN if I try hard and not really watch where I'm going, mind you I do this testing in the street in front of my house with no helmet so it's not exactly my ideal way of testing this pos... I'm about pissed I've been playing with it for days chasing my tail... fricken shop is closed today/tomorrow so tuesday would be the soonest I could get a new plug... I want to play with the CDI even change it out and see but to me that doesn't seem like something load affected..
any help would be greatly appreciated! I'm stumped and tried almost everything besides pulling the top end and cracking the block again... I'm tempted to let my kid just ride it until it goes down all the way.
