i got told by the local dealer to change the jetting on my dirtbike because of an oil leak, is this true?

Question

I've got a 2001 Honda CR125R,great bike,just has a bad oil leak around the silencer and headpipe, I called the local shop and they told me to change my jetting and needle clip position and see what that did. Do you think this is the cause of the problem, the jetting being off causing it to leak very bad? Any suggestions are much appreciated,thank you!!

Answer 1

In 2001,I was working for one of the largest HONDA dealerships in the country.I owned a 2001 CR125R and I will be the first to tell you,that particular model had horrible jetting from the factory(stock)!!There were numerous attempts by all the engine builders and riders themselves,trying to get their cr125's to run properly.With that being said,here is my suggestions.FIRST! and foremost,contact either PRO CIRCUIT or FMF RACING and ask what were the proper jetting specs for the 2001 CR125R.I had the specs written down,which I had jetted my bike to.(note:my bike was stock including the pipe and silencer and if you have changed anything from stock,you need to tell that to whomever you speak with) STOCK mainjet 380,RECOMMEND 370,STOCK pilot jet 45,RECOMMEND 37.5,STOCK needle 6BEG-20-68,RECOMMEND 6BEG20-69,STOCK needle clip position 3rd from top,RECOMMEND 2nd from top.AGAIN,double check these specs before you make any changes!!! NOW!!ALL OF THE HONDA CR 2-stroke line up leak oil from the places noted.THIS APPLIES TO JUST ABOUT ALL MANUFACTURERS OF 2-stroke engines.TO STOP THE OIL LEAK:A)re-pack the silencer with repacking that can be purchased through your dealer,B)clean exhaust spigot thoroughly with contact/brake cleaner thoroughly,and also where the pipe connects to the silencer.C)USE YAMABOND 4,which can be purchased at your local YAMAHA DEALER,and put a nice thick bead of yamabond 4 around the base of the exhaust flange(spigot),that way when you push the pipe onto the spigot,it will form a seal.LET the SILICONE CURE before running the engine.The silencer has a rubber boot which slides over the end of the pipe.USE safety wire,which can also be purchased through you dealer,to wrap around the rubber boot and twist the wire together until it is tight(you will have to cut the wire to remove your silencer in order to not tear the boot).MAKE SURE THE ENGINE HAS A FRESH TOP-END and a clean and re-oiled fresh air filter without any holes in it.Use MAXIMA SUPER M premix at 32:1 ratio(4oz.of oil to 1 gal.93 octane).

Answer 2

The carb jetting isn't going to cause oil to leak out of your silencer joint. Those jets have been in the carb since 2001 and the bike ran fine. They're not going to wear out all of a sudden. These are the main things that will cause those symptoms.
-Worn out piston & rings and cylinder. This would cause the oil in the fuel mixture to not fully ignight. Your bike is 5 years old. It's way overdue for a top end rebuild if it's never been done.
-Fuel-oil mixture is to rich on the oil side (to much oil in the mixture).
-Dirty air cleaner will cause the bike to run rich.
-Lugging the engine. 2 stroke MX bikes need to be run WFO (wide f'n open) to burn the oil in the fuel mixture.
-Crankcase seal on the clutch side is leaking, allowing crankcase oil to be mixed with the fuel mixture.
-2 strokes naturally get a build up of 2cycle oil in the exhaust pipe. Clean as much as you can by sticking a rag in the pipe with a screw driver. Then ride the bike WFO to help burn the unburnt oil in the pipe.

Answer 3

I honestly cant see why that would do it...What is the severaty of the leak on the bike? I just cant really see how the jetting would cause that, but Id call several places to get their opinion. But in my opinion, i would rebuild the carbs anyway... Its fairly cheap and if it has not been done yet it cant hurt (motorcycle carbs are a pain the butt when it comes to the details :)... Call other places and see what they say.

Answer 4

Its normal and caused by the twostroke oil you mix with the gas. your not riding it hard enough for long enough to keep the inside of the engine clean. you may also be a little sloppy about the quantity of oil your mixing with gas.
I dont know exact ratio for your bike but it will be in the 20 to 32 to one ration (probably 32:1, 1oz oil for 2 pints gas, 4oz per gal) Get 4 gals and use a pint of oil(16oz) the oil isnt geting burned and its condensing in the pipe which then leaks out. just clean it off and go faster.

Answer 5

Yes this is correct. If your bike is running good but oil still not burning in the exhaust double check you fuel/oil mix ratio. If your your good there the carb is simply letting more fuel in than is needed thus you are burning an excessive amount of oil. Use good racing oil. No cheap boat/home and garden stuff.

Answer 6

if I was you I would ignore the dealer because one way or another they are just trying to make money off from you whether the oil leak gets fixed or not.