CR125 CrankCase Breather Tube HELP

chevywaldo
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chevywaldo
Edited Date/Time 6/25/2015 5:16pm
hey guys.............

I had a recent post about my CR125 having problems with "exhaust splooge" dripping onto the swingarm. One of you guys mentioned to "check the crankcase breather hose to make sure it's not plugged".

Well I just started working on the bike to replace the Reed Valves and I came across the Crankcase breather hose. I attached some photos. So I did the obvious. I gave my breather hose a blow job and a suck job (don't laugh). It could not get any air to or from the crankcase, as if the hose is clogged. Is there a check valve in there? Is it supposed to be freely flowing air? It's kind of weird because any air in the crankcase ends up being drawn into the cylinder as the piston moves downward - as all 2-strokes do that. so why is there a breather hose and what function does it serve? I'm definitely not going to split the case and replace the hose - especially during riding season.

HELP.............





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Cygnus
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Cygnus 6/23/2015 6:27pm
6/23/2015 6:27pm
That breather hose vents the transmission not the crankshaft. Yes it should be clear.
chevywaldo
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chevywaldo 6/23/2015 6:36pm
6/23/2015 6:36pm
Cygnus wrote:
That breather hose vents the transmission not the crankshaft. Yes it should be clear.
OK , makes sense.

if that's the case, when I remove the filler plug on the trans, then I should be able to freely blow air into the trans case.............. I'll be right back........
chevywaldo
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chevywaldo 6/23/2015 6:43pm
6/23/2015 6:43pm
OK - it's good. With the trans filler cap removed the hose moves air freely.

Thanks Cygnus
Mr. Robinson 6/23/2015 6:44pm
6/23/2015 6:44pm
Yes, if you remove the plug you should be able to blow through the hose. If it is plugged, it probable has dirt in it. Run a wire up in it and see if it frees it up.

It has a little chamber in the upper part of the case that it vents off the transmission.

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Cygnus
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Cygnus 6/23/2015 6:46pm
6/23/2015 6:46pm
Good deal. What about the runner grommet on the pipe? Did you check and see if it's there or worn out? I wasn't sure if you saw my post in the other thread.
chevywaldo
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chevywaldo 6/23/2015 6:56pm
6/23/2015 6:56pm
Mr. Robinson wrote:
How were the reeds?
thanks for asking. The reeds were ok in my opinion, which I guess is good, but I was kind of hoping to find something obvious. Holding them up to a bright light, I did see some light coming through the edges of several reed petals. Mine has 6 petals. 3-4 of them had some light coming through, but it was very little. No significant physical damage to any of the petals. but what the heck, I had the entire motor rebuilt so why not put new reeds in there. the bike is a 2001 and I had a $150 gift card for amazon so I got the VForce3. I have a feeling I'll still have to mess with jetting after all this is through. 2-strokes can be a pain in the ass at times.
chevywaldo
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chevywaldo 6/23/2015 6:57pm
6/23/2015 6:57pm
Cygnus wrote:
Good deal. What about the runner grommet on the pipe? Did you check and see if it's there or worn out? I wasn't sure if you...
Good deal. What about the runner grommet on the pipe? Did you check and see if it's there or worn out? I wasn't sure if you saw my post in the other thread.
yes the rubber grommet is new and is installed. but it's not made to hold back a gallon of oil spooge Dizzy ..............consequently it drips out of there and the silencer.
Cygnus
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Cygnus 6/23/2015 7:00pm
6/23/2015 7:00pm Edited Date/Time 6/23/2015 7:02pm
Cygnus wrote:
Good deal. What about the runner grommet on the pipe? Did you check and see if it's there or worn out? I wasn't sure if you...
Good deal. What about the runner grommet on the pipe? Did you check and see if it's there or worn out? I wasn't sure if you saw my post in the other thread.
chevywaldo wrote:
yes the rubber grommet is new and is installed. but it's not made to hold back a gallon of oil spooge :S ..............consequently it drips out...
yes the rubber grommet is new and is installed. but it's not made to hold back a gallon of oil spooge Dizzy ..............consequently it drips out of there and the silencer.
Yea for sure. That packing has to be soaked. I've seen them missing before also. It makes almost that mess.
CrGuy2T
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CrGuy2T 6/23/2015 9:26pm
6/23/2015 9:26pm
Sounds more like a crank seal of your getting that much oil. Repack the silencer and go from there. Jetting could be a problem but not that bad. re pack the silencer and see what happens. Maybe even pull the pipe off flush is real good and start off fresh with that. Check it after about 2-3 rides if you have a lot again you have a seal leak.
hillbilly
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hillbilly 6/23/2015 9:44pm
6/23/2015 9:44pm
do you change the tranny oil often?

I drain into a marked cutoff jug,marked st what it takes to refill.

this way when changing the oil you see how much if any is missing.

so,if it always fills it to a certain level then all a sudden not as much comes out you know something changed like a crank seal starting to fail.
hillbilly
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hillbilly 6/23/2015 9:48pm
6/23/2015 9:48pm
and, i just noticed a case gasket in that diagram. that could be the problem also,if the pro that built it didnt get that gasket on right it can pull oil thru between the cases.
hillbilly
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hillbilly 6/23/2015 9:55pm
6/23/2015 9:55pm
also,wash that thing before tearing into it,I see a big dirt clod about to fall into the hole that will require more gift cards.
chevywaldo
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chevywaldo 6/24/2015 5:08am
6/24/2015 5:08am
the crank seals were recently replaced. I did one myself just a few weeks back. I checked my trans fluid yesterday and it seems full. Good indication that it's likely not leaking or burning trans oil. when I lean the bike over just a little bit, it drips out of the overflow hole (when drain screw is removed). So I don't think I have a seal problem. However the trans fluid is milky darky gray color. Is that normal? It only has 2-3 hours runtime on it.
hillbilly
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hillbilly 6/24/2015 7:03am
6/24/2015 7:03am
chevywaldo wrote:
the crank seals were recently replaced. I did one myself just a few weeks back. I checked my trans fluid yesterday and it seems full. Good...
the crank seals were recently replaced. I did one myself just a few weeks back. I checked my trans fluid yesterday and it seems full. Good indication that it's likely not leaking or burning trans oil. when I lean the bike over just a little bit, it drips out of the overflow hole (when drain screw is removed). So I don't think I have a seal problem. However the trans fluid is milky darky gray color. Is that normal? It only has 2-3 hours runtime on it.
id have to see it,a grey color is from clutch wear,its aluminum.

milky to me means the water pump sealnis leaking water into the tranny oil by the pump shaft. coolant level full?

it doesnt take a teaspoon of tranny oil to make that mess on thecswingarm,

did the pro thst built it have the cases split apart? that gasket has to lay on a very narrow piece of case and if he missed or screwed it up then a tiny amount of oil would leak thru . Just throwing thst out there. most bikes dont have s gasket there,you put a gasket liguid on the surfaces.
chevywaldo
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chevywaldo 6/24/2015 8:12am
6/24/2015 8:12am
chevywaldo wrote:
the crank seals were recently replaced. I did one myself just a few weeks back. I checked my trans fluid yesterday and it seems full. Good...
the crank seals were recently replaced. I did one myself just a few weeks back. I checked my trans fluid yesterday and it seems full. Good indication that it's likely not leaking or burning trans oil. when I lean the bike over just a little bit, it drips out of the overflow hole (when drain screw is removed). So I don't think I have a seal problem. However the trans fluid is milky darky gray color. Is that normal? It only has 2-3 hours runtime on it.
hillbilly wrote:
id have to see it,a grey color is from clutch wear,its aluminum. milky to me means the water pump sealnis leaking water into the tranny oil...
id have to see it,a grey color is from clutch wear,its aluminum.

milky to me means the water pump sealnis leaking water into the tranny oil by the pump shaft. coolant level full?

it doesnt take a teaspoon of tranny oil to make that mess on thecswingarm,

did the pro thst built it have the cases split apart? that gasket has to lay on a very narrow piece of case and if he missed or screwed it up then a tiny amount of oil would leak thru . Just throwing thst out there. most bikes dont have s gasket there,you put a gasket liguid on the surfaces.
thanks Hillbilly.

yea - it's kind of gray I guess - dark gray. When I put the oil in it was clear and gold in color. But like I said - the level seems full so it doesn't appear to be leaking into the case.

I'll check the coolant level when I get back home - pretty sure it's good. whenever I've checked the level in the past it's been full.

the "pro" that rebuilt the motor definitely split the case and replaced all bearings, seals, gaskets, rod, piston, etc. Did he screw it up? Possibly. Don't know. All I know at this moment is that it's riding season and I'm not pulling that motor out as long as the bike is good enough to ride - even though it's not running perfect and has "issues". This weekend I will put in a new reed valve, replace the silencer packing, run a hotter plug, use lower flash point 2-stroke oil, and that's about it. If I still have "spooge" and/or low-mid range performance issues - I'll keep working on it - probably jetting stuff.
dazzlindino 6/24/2015 8:15am
6/24/2015 8:15am
...put it together...
...warm it up...then go ride it down a straightaway WFO to burn all the oil in the pipe and silencer....
...watch it smoke like BBQ for a while....you just aren't riding it hard enough....
chevywaldo
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chevywaldo 6/24/2015 8:33am
6/24/2015 8:33am
dazzlindino wrote:
...put it together... ...warm it up...then go ride it down a straightaway WFO to burn all the oil in the pipe and silencer.... ...watch it smoke...
...put it together...
...warm it up...then go ride it down a straightaway WFO to burn all the oil in the pipe and silencer....
...watch it smoke like BBQ for a while....you just aren't riding it hard enough....
I know what you're saying. I'm not a "racer" (but I am aggressive) so I don't have the bike in the "powerband" all the time. Much of the time I ride I'm at mid-rpm range. Having said that, I've watched other riders and have listened to the bikes and the RPM that they are running and I agree with what you are saying. Most of the "racers" out there always have their bike at high rpm range. I'm trying to do that more. I did it last week when I went riding. Trying to keep it at high rpm more - instead of switching to the next higher gear - staying in the gear that I'm in. I'll keep practicing and get better at feathering the clutch when coming out of a turn, which I wasn't doing until recently.

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dazzlindino 6/24/2015 8:44am
6/24/2015 8:44am
dazzlindino wrote:
...put it together... ...warm it up...then go ride it down a straightaway WFO to burn all the oil in the pipe and silencer.... ...watch it smoke...
...put it together...
...warm it up...then go ride it down a straightaway WFO to burn all the oil in the pipe and silencer....
...watch it smoke like BBQ for a while....you just aren't riding it hard enough....
chevywaldo wrote:
I know what you're saying. I'm not a "racer" (but I am aggressive) so I don't have the bike in the "powerband" all the time. Much...
I know what you're saying. I'm not a "racer" (but I am aggressive) so I don't have the bike in the "powerband" all the time. Much of the time I ride I'm at mid-rpm range. Having said that, I've watched other riders and have listened to the bikes and the RPM that they are running and I agree with what you are saying. Most of the "racers" out there always have their bike at high rpm range. I'm trying to do that more. I did it last week when I went riding. Trying to keep it at high rpm more - instead of switching to the next higher gear - staying in the gear that I'm in. I'll keep practicing and get better at feathering the clutch when coming out of a turn, which I wasn't doing until recently.
...there is no harm in not being fast...just have fun...
...all you need to do is run it hard before you get on the track and after to keep it running spooge free....
Mr. Robinson 6/25/2015 12:53am
6/25/2015 12:53am
Waldo, check your float level while you have the carb off. Ever see fuel dripping or running from the carb vents?
chevywaldo
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chevywaldo 6/25/2015 5:01am
6/25/2015 5:01am
Mr. Robinson wrote:
Waldo, check your float level while you have the carb off. Ever see fuel dripping or running from the carb vents?
yes sir I was planning on doing a quick carb rebuild and cleaning since I got it out. I set the float level a couple months ago. should be fine but I'll check again anyway. Only takes about 15 minutes to completely rebuild and clean that carb. Very simple design.

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