Broken Crankcase

[samioroi]

Hello,
I dont know if i post is eligible in this section or on this site, but i am in a desperate situation and hence request for your help.
just recently my superbike(600cc) starter motor stopped working. I took the motor out and checked it, it was fine. On opening my oil pan, I found bits of my oil chain guide broken into pieces and the oil pump sprocket. My oil pump chain and the guide in the upper crankcase is broken. I can replace the chain. But the local mechanic says the oil pump will not generate enough pressure because the chain guide is shattered. I cant afford to buy the complete set(2500$). I am clueless as to what should be my next step. Cant seem to figure out the significance of the guide in the lower crankcase. Can i weld the bits back or will welding warp the engine casing? Can anyone suggest what should I do. Really appreciate your help.
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[TurboLag]

Either weld or HTS2000 should work

[autogyro]

Dont want to put a downer on this but if the starter was OK but the engine didnt turn over are you sure the problem doesnt go further than just the oil pump drive chain?
At an initial guess, the reason for the chain guide cast in the casing is to make sure the chain runs strait over a long run of links.
Not the best design but limited by packaging.
The repair which should be OK using quality alloy welding but you must fully check the chain run.
If the oil pump has not been working for some time then you must also expect a seized engine.
If it does start check the oil pressure when hot and make sure the oil and filter are changed.

[samioroi]

Dont want to put a downer on this but if the starter was OK but the engine didnt turn over are you sure the problem doesnt go further than just the oil pump drive chain?
At an initial guess, the reason for the chain guide cast in the casing is to make sure the chain runs strait over a long run of links.
Not the best design but limited by packaging.
The repair which should be OK using quality alloy welding but you must fully check the chain run.
If the oil pump has not been working for some time then you must also expect a seized engine.
If it does start check the oil pressure when hot and make sure the oil and filter are changed.

The engine didnt start as the chain was clogging at one end of the crankcase, restricting the free movement of the clutch and hence the starter. The clutch is fine with slight amount of wear but no damage to functional areas. The engine hasn't seized as it has run only for a very short duration. I haven't quite understood the reason provided by you for the chain guide in the casing.
thanks for your reply,