Bad wiseco crank

I paid someone to rebuild my cr250r with complete wiseco parts (crank, piston, bearings), bored to 265cc, new sleeve, 32:1 HP2 VPC12/93 Mixture. The bike was broken in fine, and warmed up prior to riding. 3mins into my vacation going towards some trails.. the rod bearing is shot! Piston/kickshifter will not move up or down. I need to take the cylinder off to check out my sleeve.. ect.

Now I have to pay for another rebuild.. :lol: :lol: :worthy:

Country of origin is more important than brand when it comes to bearings.

This is why I only use Honda OEM parts, they cost a little more for a reason :worthy:

2nd that.

This is why I only use Honda OEM parts, they cost a little more for a reason :worthy:

I heard alot bad things about Hot Rod Cranks not saying there all bad but I heard more bad stories about them than good.

My CR500 is using a IMS Rod, Honda stock Rods are no longer made.

And Wiseco Piston I like Forged Piston over Cast.

I paid someone to rebuild my cr250r with complete wiseco parts (crank, piston, bearings), bored to 265cc, new sleeve, 32:1 HP2 VPC12/93 Mixture. The bike was broken in fine, and warmed up prior to riding. 3mins into my vacation going towards some trails.. the rod bearing is shot! Piston/kickshifter will not move up or down. I need to take the cylinder off to check out my sleeve.. ect.

Now I have to pay for another rebuild.. :lol: :lol: :worthy:

When it comes to crank & main bearings/seals I trust nothing but OEM. Some use aftermarket without issue, but I don't trust anything but OEM for a bottom end job since I know my first one lasted 11+years.

Did you'r bike lean seize do to air leak It could of been a bad crank or bad bearings but I would start looking for a air leak even you put a anouther new crank and topend Bearings Ect in if you have a air leak it will blow up again plan on it.

Remerber NEW still can blow up if it not right.

Did you'r bike lean seize do to air leak It could of been a bad crank or bad bearings but I would start looking for a air leak even you put a anouther new crank and topend Bearings Ect in if you have a air leak it will blow up again plan on it.

Remerber NEW still can blow up if it not right.

I would totally agree with you there. Find out the cause of the failure. If it is a seal or gasket, make the shop/mechanic pay for the mistake. If it is just a bad crank, call Wiseco.

Pistons fail before cranks during a lean condition. Cranks fail due to dirty air, excessive wear, or chinese bearings.

Nomaly when the main seal go's bad the crank go's first.

Pistons fail before cranks during a lean condition. Cranks fail due to dirty air, excessive wear, or chinese bearings.
Cranks fail due to dirty air, excessive wear, or chinese bearings.

And don't forget improper installation. Most aftermarket cranks I've seen fail with low hours were not installed properly.

Nomaly when the main seal go's bad the crank go's first.

A leaking main seal will have ZERO efect on the crank. It will make the bike rev up, and seize a piston however.

As the crank assembly was replaced, improper engine assembly can be ruled

out. If it was a crank rebuild, then I would question that, but complete cranks are assembled at the factory.

You did however rebore oversize to 265cc. This will increase the compression ratio, requiring better fuel to overcome detonation, pre ignition.

You were running race gas, and the problem occurred before a heat issue should have become a detonation issue, so I will rule that out.

Bore alignment should be checked. With the rebore, perhaps the new bore is not square to the crankcase, or maybe its bored off centre, putting stress on the rod big end.

This MUST be checked, as it is really the only thing that could have caused the problem except for poor manufacturing of the crank.

Good luck, and keep us posted.

I still need to take the cylinder off, but I am pretty broke right now, and kind of sick of the bike at this moment since I overhauled the entire thing from controls, motor, to bearings, wheels, tires :lol:. The bore was done by a digital readout from Rob Brown 4PR in Chicago along with the entire motor. I took the head off and the top of the piston looks brand new still.

The wiseco crank was on back order for months due to a new vendor.. and I got one of the first ones.

I called wiseco and they said send the crank to them.. but who's going to pay for my labor and possible new sleeve again. When the rod goes out it puts alot of pressue on the piston which carrys to the sleeve. i can only imagine the outlook when I take the cylinder off. This was a brand new motor with reed cage, parts, cases, sleeve, flange! :worthy::lol:

This could possible be an air leak.. but all the gaskets look in place and the cases and covers are all tight.

Also.. the bike was running rich for the first 30-40mins of break in

I called wiseco and they said send the crank to them.. but who's going to pay for my labor and possible new sleeve again.

You'll never know unless you send it in for evaluation. (hint) But like many people have pointed out, a leaking main seal can cause a similar, premature failure. You need to give Wiseco a chance to look at it before deciding the root cause yourself.

I still need to take the cylinder off, but I am pretty broke right now, and kind of sick of the bike at this moment since I overhauled the entire thing from controls, motor, to bearings, wheels, tires :banana:. The bore was done by a digital readout from Rob Brown 4PR in Chicago along with the entire motor. I took the head off and the top of the piston looks brand new still.

The wiseco crank was on back order for months due to a new vendor.. and I got one of the first ones.

I called wiseco and they said send the crank to them.. but who's going to pay for my labor and possible new sleeve again. When the rod goes out it puts alot of pressue on the piston which carrys to the sleeve. i can only imagine the outlook when I take the cylinder off. This was a brand new motor with reed cage, parts, cases, sleeve, flange! :banana: :banana:

This could possible be an air leak.. but all the gaskets look in place and the cases and covers are all tight.

Also.. the bike was running rich for the first 30-40mins of break in

How could you know the crank bearing siezed if yo have not pulled it apart? Did you scan it with a tri-corder? :worthy:

It's pretty standard that if the bike seizes and then remains seized once cooled off that you've had a bottom end failure. The con-rod bearing is almost always the first to go, catastprophically. Mains are usually the first to fail, but they make themselves known with leaky seals. Con-rod bearings are almost always the cause of a catastrophic lock-up.

If it makes you feel any better, I just melted the connecting rod bearing on my bike. I know the cause, excessive hours. But, there was no damage to the head or cylinder after the failure. The piston had a few scratches and a stuck ring because of the debris from the thrust washers. When the bearing rollers finally squeezed out of the crank, they were so hot and plastic they were actually softer than the aluminum crankcase and did no damage as they gently brought everything to a halt.

Can we get an update?

Can we get an update?

the bike is sitting

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