I have a yz 125 and it has a slow leak of oil could this just be some tighting of bolts?

Year of the bike?





Unfortunately its probably not as simple as tightening some bolts. It could be one of many, many things. Engine cracked from riding rough....weather related... etc etc. Try and find the leak and investigate what possibly could of caused it. Do it quick before it gets worse. You may be able to find a solution to seal it up but you will most likely have to take it to the shop and get it fixed and that may put a dent in your wallet.I have a yz 125 and it has a slow leak of oil could this just be some tighting of bolts?
Take all suggested steps to isolate the point of leak BEFORE removing the engine.If it's the drain plug, then you may only need to replace the sealing washer.If it's a mating surface, then you may need a new gasket.If it's the clutch cover for example, check tightness of all bolts, but as stated, DON'T overtighten them.It's not unheard of for bolts on dirt bike to work loose.Is there a breather on crank cases? If so, make sure it's not blocked.How serious is the leak? If it's not too bad, then you could live with it as long as there is no danger of oil level becoming too low. All depends on age of bike and how long you ride it for between checking oil. For example, if it's an old bike which is only losing a little oil and you ride for 10 minutes at a time, you could get away with keeping it topped up. Ideally, find the leak and rectify it.


My own dirt bike has a constant oil leak from kickstart shaft, but replacing the seals can involve a full engine stripdown and leak is not bad enough to warrant this so I keep it topped up. On the plus side, it means transmission is getting a small amount of new oil on a regular basis!I have a yz 125 and it has a slow leak of oil could this just be some tighting of bolts?
I agree with your first respondent...There are several causes of oil leaks, like seals or gaskets that are defective, cracks or damage to casings and of course loose bolts. But first it's best to take the bike to a workshop where they have a steam cleaner and get the engine all clean. Then it will be possible to see exactly where the leak is coming from. Even if it's just loose bolts, they need to be tightened to the correct torque and not over-tightened. Tightening bolts too much (';beyond specifications';) is not a good idea because the bolts are usually much harder than the alloy parts and if done up too tight, you can strip threads in the alloy (expensive!) or even crack a casting (very expensive!!).





So -- get the engine cleaned and then get it inspected by a good mechanic. If you don't know anyone then ask around to find a mechanic you can trust, or take someone with you who knows quite a lot about bikes so you don't get taken for a ride.
Start out cheaply. Use a light and see if any of the case screws are missing in the area of the leak. If it's dripping down from the skid plate you may not be able to inspect the engine without removing it from the bike.





Before taking it anywhere I would remove the engine. Take off the exhaust, unhook the coil wire to the plug. Remove the chain. Take off the carb and leave the cables attached and hang out of the way. Unhook the main wiring harness at the plug. Drain your coolant. etc.





Once on the bench degrease the entire engine, clean it up real good. Than let it sit for a few minutes and look to see if you can spot the leak. Look for missing screws. Make sure the drain plug is tight.





If it's the main cases you'll need to tear the whole engine down to replace but it's not a big deal. Take pictures with a digital as you go and number the bolts and parts in bags. If your careful you can dismantle and reassemble relatively easy.





I would fix the oil leak before you seize something.
tightening the bolts is not the answer here. More than likely you have a gasket that is worn out and nees to be replaced, and chances are that you have never replaced it before...


Tightening the bolts is not a good idea. The bolts are tightened to manufacture specs and if tightened more, could cause damage to the bolt or side cases. If you strip a bolt in a side case, it is expensive to repair.....