yz125 connecting rod getting stuck HELP!

just got my crank back from rebuild installed it with new bearings then closed the case and then i put a new piston and cylinder on. The connecting rods bottom end part seems to be getting caught up in the from of the cases. any suggestions on what to do. also i noticed the pistons front exhaust arrow is not perfectly straight. bad crank rebuild? or did i do something else wrong.

did you get a new rod, or use the old one with new bearings?? could be worn bad, or bad crank job. it happens. in some cars the rod is posed to face one way only, don't know if bike do that too.. never seen an arrow not point straight, something ain't right.....

somethings wrong take it back to the shop and get refund or fixed.

all new bearing and rod. would a slight bend in the rod cause this or the fact that the dealership didnt true the crank.

i think most bike rods are the type of metal that will break before it bends. i think the problem has to be in the crank

well i just got a cheap new crank off ebay and am going to try that. this is my project bike and thats all i need for reassembly. if i get the same effect then i dont no what it maybe. ill post what happens when i get the other crank in.

They might have put a veshra rod on it which will cause it not to clear the cases when rotated. you will have to clearance the front and back of the cases to accommodate some aftermarket rods. Some of these rods are larger on the big end than the OEM part.

that's why I stick with OEM parts, I hate surprises.

Take a die grinder and remove some material from the cases.

ill wait for the other crank before i do that

I think you are smart not to mod anything until you find out what's hokey here. Your crank probably wasn't trued correctly.

When they fail to true it well, the rod bearings turn fine but everything binds up when you sandwich it in your new case bearings...

I hope you get it worked out. Sounds like a PITA :thumbsup:

There's nothing wrong with your crank, I've done thousands of cranks and this is common with some aftermarket rods.

I kinda ran into the same problem when I did my top end rebuild. Everything moved freely until I put any type of torque on the cylinder nuts. Turns out the cometic gasket was way thinner than the oem gasket and the crank was hitting the cylinder when tightened down. I just used double gaskets and I was fine.

ill check that also thanks for the idea. the gasket kit i have is cometic so ill check that out.

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