Can I replace the oil seal behind the chain drive sprocket on a 1987 honda Xr2504 from the outside?

I have a 1987 Honda XR250R dirt bike and the oil seal behind the chain drive sprocket is leaking. I can get the seal easy enough but do I have to disassemble the transmission to replace this seal or can I do it from the outside?Can I replace the oil seal behind the chain drive sprocket on a 1987 honda Xr2504 from the outside?
countershaft seals on all japanese motorcycles are designed with a ridge on the outside diameter and the cases are designed with a groove to hold the seal in preventing it from coming out any other way except by splitting the case halves.It is possible to tear it out from the outside but it isn't designed or recommended to do so.Can I replace the oil seal behind the chain drive sprocket on a 1987 honda Xr2504 from the outside?
I don't think so.


The XR250 was one model that the crankcase had to be dis-assembled.


Your year might be one of the exceptions where it can be done.


If the outside edge of the seal is flat, the seal can be replaced from the outside of the engine.


If the outside edge of the seal has a raised edge, the engine has to be dis-assembled.
try a slide hammer with a hook it should come out. If no slide hammer you can also take a small punch and go from the top of the seal bending the housing and this will loosen it up so you can remove it.
if , you can get to the sprocket from the out side, then you can get to the seal. If you are working on the bike without a manual, that is your first(and possibably your last) mistake.
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