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Crankshaft compatibility?

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I'm about to get started on an old '95 yz 250 project. After pulling the cylinder off and inspecting things, I found some play in the connecting rod. I've searched everywhere for a new crankshaft but can't find a thing, and I want to do rhis right. I'm wondering if there is a difference from 95-96. I know the bike changed drastically but I didn't think the engines did. 96-98 cranks are still available so can I use one in my 95? Or am I screwed and have to rebuild the one I have? I've always thought the engines were the same from 93-98. Please help!

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I'm about to get started on an old '95 yz 250 project. After pulling the cylinder off and inspecting things, I found some play in the connecting rod. I've searched everywhere for a new crankshaft but can't find a thing, and I want to do rhis right. I'm wondering if there is a difference from 95-96. I know the bike changed drastically but I didn't think the engines did. 96-98 cranks are still available so can I use one in my 95? Or am I screwed and have to rebuild the one I have? I've always thought the engines were the same from 93-98. Please help!

 

All of crank side bearings, seals, connecting rods, and primary drive gear etc are same. 

There will be no problem about compatibility at the left side oil seal to the primary drive gear fixing nut. The change of the right side crank will not influence their compatibility 

However, flywheels are changed. The change depends on the change of 2 pole coil to 4 pole coil. It means those flywheels didn't have electrical compatibility.

With considering the parts # of left side crank was changed, we can't read out their structural compatibility.

Probably the taper angle will be the same. But there is a possibility of the change of the position.

If someone has 96-98 motor and he can measure the length of the left side crank shaft taper, it will be sure.

 

Or. search ebay. http://www.ebay.com/sch/i.html?_odkw=yz250+crankshaft+93+-KX&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xyz250+crankshaft+93+-KX+-balls&_nkw=yz250+crankshaft+93+-KX+-balls&_sacat=0

And you can also rebuild your crankshaft.  There are some connecting rod kits from Wiseco, Hot rod, IMS and YAMAHA. 

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All of crank side bearings, seals, connecting rods, and primary drive gear etc are same.

There will be no problem about compatibility at the left side oil seal to the primary drive gear fixing nut. The change of the right side crank will not influence their compatibility

However, flywheels are changed. The change depends on the change of 2 pole coil to 4 pole coil. It means those flywheels didn't have electrical compatibility.

With considering the parts # of left side crank was changed, we can't read out their structural compatibility.

Probably the taper angle will be the same. But there is a possibility of the change of the position.

If someone has 96-98 motor and he can measure the length of the left side crank shaft taper, it will be sure.

Or. search ebay. http://www.ebay.com/sch/i.html?_odkw=yz250+crankshaft+93+-KX&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xyz250+crankshaft+93+-KX+-balls&_nkw=yz250+crankshaft+93+-KX+-balls&_sacat=0

And you can also rebuild your crankshaft. There are some connecting rod kits from Wiseco, Hot rod, IMS and YAMAHA.

Awesome info, thanks very much. My cousin has a 98 so I'll check his flywheel side. Thanks again

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Look up the part # also the parts like bearing, fly wheel etc.

I tried that, they're not even close, save for the bearings and seals.

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Awesome info, thanks very much. My cousin has a 98 so I'll check his flywheel side. Thanks again

 

I noticed one possibility that I overlooked. Diameters of crank weights can be different.

Because 95-96 cranks use same connecting rod and their strokes are same, it will be not so much possibility.

But I don't have any fact to completely deny it. Please note the possibility.

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