Yes, It will leak oil. How much will depend where the hole is. When the engine is running the oil is a pressurised system so it won't be supplying enough oil the the moving parts of the engine.
Take a photo with your phone and there is a button on the bottom of the comment box. Use that to add photos.
As a general rule If the cylinder head has ANY damage like holes and cracks Replace it. A cylinder head is cheaper than a replacement engine or a bike.
No, use whatever they recommend. Using wrong lubricants can ruin engines. As I said last night, this is not a well know motorcycle. It is a Honda 90 clone.
That is about right for a 110cc step-through scooter. They are very unaerodynamic. For a small engine it also depends on your weight and how much of a sail (wind resistance) you present to the oncoming air.
https://www.google.com/search?q=vuka+xl110+specs
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This is a short, it could be the wire from the fuse chafing on the frame, follow it thru to the wiring loom, failing that then look at all te wiring for a split or exposed wire.
I take help from online websites that have this service like helping in repair some like reliable-store have instant help.. others are a bit slow which I don't prefer... rest is up to u.. U can also get free manual works fine .
Is the breather/vent on the fuel cap blocked? Try riding it and d when the symptoms appear again, remove the filler cap. If you hear air being sucked in when you first open the cap then the vacuum in the tank is causing the carb to be starved.
There are many reasons why an engine doesn't run as it should...fouled plug, air/fuel ratio wrong, blocked air filter, fuel starvation, timing wrong to name a few.
The easiest to check yourself would be the spark plug. Take it out and check the condition and colour. If it is sooty then you are running too rich. If it is oily then possibly a major engine problem. If the electrode gap is too small or too big then it won't fire correctly. If the the electrode is worn too much or the ceramic cracked then again it won't work as it should.
Running rich could be as simple as a blocked air filter so check out its condition. If blocked then not enough air is getting in to burn the fuel efficiently causing it to run rich, because rich running does not mean too much fuel getting through, it also means not enough air and that screws up the correct ratio. Your fuel filter may be blocked and not enough fuel is getting through....enough to idle or run slow but not enough to run under load. Your filler cap may not be venting properly, but that can be checked by running without a cap, but be careful. If in doubt change for new parts and see if that works.
Those are the easiest things to check, but if it is a weak spark or incorrect timings then that is more complicated and would require a mechanic to check over with the correct equipment.
Hope that helps, Steve.
