2 stroke newb needs help...plz

[haole808]

i am relatively new to the do it yourself mechanics on my 09 ktm 125sx.  I went on a vaction and my bike sat for about two months.

before i left i made sure to run the carb dry and not leave any gas in it.  When i came back and was ready start the bike she fired up first kick.  I have a fresh spark plug, clean carb (took apart the float chamber to inspect), and a fresh oil change in the gearbox.  She sounded great, idled great but when it was time to go for a cruise she was all talk no walk.  the engine would scream but i would barely get going.  Even after she was all warm still never got going like i've been used to. had to constantly rev just to keep on creeping a long.

Now I am basically stuck and I dont know where to take it from here. 

 

Can anyone tell me what i should be looking for or trying to do next?  possible clutch problem? resevoir seems to be full.  Could  I have missed somthing when inspecting the carb? All advice is greatley appreciated.

 

thank you

[avocasingletrack]

Sounds like maybe a clutch cable adjustment or the clutch is having probs ... try adjust the clutch cable

[Red141]

What kind of oil did you put in?

[ADHDave]

Dont try to adjust your clutch cable. Adjusting the cable on a hydraulic clutch ends in disappointment every time. It does sound like the clutch is slipping though. So the second reply might be on to something.

[terdog]

 

 

Sounds like maybe a clutch cable adjustment or the clutch is having probs ... try adjust the clutch cable

KTM's have a hydraulic clutch. The only adjustment is to bleed the line.

Lay the bike on the clutch side for awhile to let the oil get back into the plates.

[avocasingletrack]

haha yeah...i was just posting on a thread about a yz125...brain fart...haha

[haole808]

Red141....I have motorex 15-50 in the gear box and motorex hydraulic fluid 75 mineral oil in the clutch reservoir/line...was thinking about using clutch piston to check for air bubbles...also gonna lean my bike on the side to hopefully get plates saturated....I'll kkeep updates coming tmrw...thank you everyone for all your responses!!!!

[ADHDave]

The plates should grab in the absence of pressure  though right? Its only when you stroke the master cylinder to pressure up the slave that the clutch should slip. And you would feel a lack of resistance in the Lever. Not to mention the lever would not return.

 

The oil you used doesnt have any crazy friction modifiers does it? Its weird that the bike was fine before the oil change. If you have it laying on its side you may want to pop the clutch cover off and inspect your plates and basket. If the fingers on the basket are worn it could be keeping the plates from hooking up.

Edited October 30, 2013 by ADHDave

[terdog]

 

 

 Not to mention the lever would not return.

Unless theres air in the line.

 

 

 

Its weird that the bike was fine before the oil change

I agree. My 300 has sat for longer periods than your vaca.

 

What oil did you use?

[deeman]

Also - just to clarify, will the bike run fine in neutral?  No hiccups, bogging when revved or any other issues? 

 

If the bike runs 100% when in neutral I would also suggest a clutch issue as well.  If you have issues when the bike is in neutral it's something else.

[terdog]

 

 

 

What oil did you use?

 

Nevermind,I can read! The motorex should be fine. Are you sure that you have the right amount? Maybe drain it out into a pan so that you can re-use it if all good. Check the amount.

[haole808]

I used the manual specs on the amount of oil necessary and double check using the over flow bolt...the bike runs absolutely cherry in neutral nthing sounds wrong...there is ffluid in the clutch res and the lever returns after being squeezed....I guess the next thing to do wwould be to inspect the clutch case...

[Supr Sloguy]

I see you're in Hawaii. I'll gladly fix it for free if you pay travel

[haole808]

So....took apart the clutch case and pulled out the plates....all look fine very minimul if any wear....however the clutch basket does have the slightest looking grooves where the teeth of the clutch plates sit/rest..but....when I go to feel these "grooves" on the basket it feels perfectly flat...I'm attaching a picture for everyone to check out....I read somewhere that filing the grooves down could help the clutch plates come "unstuck" any idea what grit to use?

Right now I am soacking the clutch disks in 15-50 motor oil

[haole808]

Also does any one have a measurement in ft. Pounds for the amount of torque that should be used when re-assembling the bolts w the springs on the pressure plate??? And also for the bolts on the outside case cover???

[terdog]

 

 

and double check using the over flow bolt.

You would be better off never even touching that bolt. Leave it in Place! There have been many who have stripped it, causeing more headaches.

Just measure your oil then put it in. Its only a "bath", not under pressure.

I typically add a bit too much just to be safe.

Your basket looks better than most of its age.

 

When is the last time that the clutch has been bleed? I dont believe that to be a problem, as its job is only to DIS-engage the clutch. I would think more of the plates and springs. But I find it very odd that this all started with an oil change! Have you used this MOTOREX oil before?

[ADHDave]

Air in the line would cause the opposite problem. If you had air in the line you would not be able to make enough pressure to push the slave cylinder. So the clutch would always be engaged. Your clutch is always disengaged. So something isn't returning to its normal position. Either the master cylinder is holding pressure in the circuit (not very likely). The slave cylinder is stuck (more likely). Or I assume there is a push rod because the slave cylinder is on the opposite side of the basket, So perhaps that's stuck. OOOOOOOORRRRRRR, the most simple and most common cause is that your springs are weak. That's just hard to believe because the bikes so new. 

 

I could be wrong about the air thing, but as a heavy equipment mechanic I deal with alot of hydraulics, and it doesn't make sense to me that air could cause the pressure plate to push against the springs. Air compresses a lot. Fluid compresses almost not at all. Thats why hydraulics work.

 

Now on to the soaking of the plates. Again I believe you are 180* off. Oil is nessecary for the plates to slip, and seperate. If the plates were to dry they would hang up. Not slip.

 

Hopefully this helps. So you don't waste any more time.

[haole808]

So been trouble shooting the past few days and found a leak in my master cylinder where the plunger meets the rubber seal underneath the reservoir...since a new master cylinder is almost 300$ was gonna buy the rebuild kit.

On the bottom of my master is a 10...I've only seen kits for 9.5mm or 10.5mm.....has anyone bought one of these kits before??? What is the measurement for and do these kits help permanently fix the problem???

Could really use some feedback thanks everyone

[terdog]

Did you ever try to bleed it? My 125 would not bleed unless I moved the lever OUT a bit.

[KTMRider4Life]

So been trouble shooting the past few days and found a leak in my master cylinder where the plunger meets the rubber seal underneath the reservoir...since a new master cylinder is almost 300$ was gonna buy the rebuild kit.

On the bottom of my master is a 10...I've only seen kits for 9.5mm or 10.5mm.....has anyone bought one of these kits before??? What is the measurement for and do these kits help permanently fix the problem???

Could really use some feedback thanks everyone

The difference in 9,10 etc is the size of the plunger, the KTM dealer can get any of the rebuild kits. For me after rebuilding my 10 I went with a 9.5 to make the pull a little easier. I was able to get a brand new one off of Amazon for a little more than $100 I believe. If I were in your shoes that's what I would do.