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2013 ktm 125sx clutch not working properly

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Hello, I have a 2013 ktm 125sx and it seems as if the clutch isn't engaging completely. When I start the motorbike and hold in the clutch and try putting it in first gear it does not really want to work. It sounds like it is grinding gears. I can shift it into second then back down to first but not straight into first. And when I do have it in first the bike still wants to drive forward even when I have the clutch in. And when the bike is off and I pull the clutch in, I can't push the bike. It is the same as if I don't have the clutch engaged. It is a pretty much new bike. Only have like 30 hours on it. And I bleed the clutch and it still does this.

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a bit of clutch drag when engine is off and clutch pulled in and in gear is fairly common

as for the other problem only thing i can think of is that when bike was new the measurement for the gasket between slave cylinder and engine face was borderline to big but worked , you can get different thickness gaskets from the dealer , if yours has and o ring then sorry i don't know what could be the problem

 

what i did was pull the slave cylinder off bike and took some measurements but i could actually hold the slave cylinder against the mating surface on the motor with the gasket removed so i just bought the thinnest gasket available (0.35mm thick) , solved a lot of my clutch issues

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Good answer. Just to add to it, KTM has another of its famous dimensions, this time Y. You measure from the sealing surface of the slave to the end of the push rod. 2.5 - 2.8mm use the 0.75 gasket, 2.8 - 3.0mm use the 0.50 gasket and 3.0 - 3.3mm  use the 0.30 gasket. There can be other reasons like a notched basket, worn/stuck plates, too thick gear oil, too much gear oil, air in the system. Take your oil filler cap off and pull the lever in to see how much the plates move. You should also be able to see if it is notched, although the main result of this is difficulty starting it in gear with the lever pulled.  Don't remove the oil level bolt on the clutch side when you change the oil as it strips very easily. Hope this helps. Bob.

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We did just change the gaskets on it before it started doing this. We ordered a complete engine gasket set and it came with 3 different gaskets for the clutch and we didn't know why it had 3 but I guess they are just the different thicknesses so maybe we put a to thick gasket in. I will try putting a different gasket in and let you know if it helped. Thanks

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Most peeps just use the 0.50 gasket. Your kit does come with the 3 alternatives, hopefully one of the 2 thinner ones will solve your issue

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It was working but now it isn't again. When I pull in the clutch clutch fluid comes out of the little hole on the sidw of the resivor cap. And it gets air there. Should I do like that or how do you fix that? And also when I look into the oil filler hole at the clutch plates. When I pull in the clutch only one plate moves toward the clutch cover. Sometimes it doesn't even move. Are they all supposed to move or how does that clutch work?

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Hmm. Clutches are pretty simple things. The clutch basket -the bigger part with the fingers you can see through the oil filler bolt - is driven by the crankshaft. There is an inner hub which drives the gearbox. The clutch plates are either smooth metal or fibre faced. The fibre ones have 'teeth' around their outside which sit between the fingers in the basket. The smooth ones have 'teeth' around their inside which mount on splines on the inner hub which is smaller circumference and sits inside the basket. They are mounted alternately. The pressure plate is mounted on the outside of the inner hub and screws into it with 5 springs and screws. This provides enough pressure and friction to hold the smooth and fibre plates together, giving you drive. You see the pressure plate moving out when you pull the lever in. When you pull your lever in, the slave cylinder 'diaphragm' expands outwards (you cannot compress liquid so something has to move) and the ball in the middle pushes a rod which runs through and pushes the pressure plate outwards against the  pressure of the 5 springs, releasing the friction on the plates and disengaging the clutch. Obviously when you let the lever back out you release the pressure and the pressure plate moves back in and pushes the plates back together, reuniting the crankshaft drive and gearbox. There are various things you could look at - there may be air in the system, your piston seals in the master may be leaking, the clutch plates could be stuck together, your basket maybe so notched the fibre plates are finding it difficult to move, the steel plates may be warped (usually go blue). The inner hub tends to last a long number of hours. The slave can leak as well but quite rare on the 125s in my experience.We run a couple of 125s but seldom have an issue, but I change the fluid regularly and it get new plates at the first sign of slip. If you do decide to have a look at your plates you usually need a new gasket. If they and the basket and hub are fine, be careful remounting the screws and springs. You have to mount them all a little at a time and do them up to the correct torque in rotation - if you do 4 for instance the pp goes squint and you may well strip the 5th one. Perhaps kxrob will come on with some suggestions as well, but I will go for air in the system.. Hope this helps. Bob.

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Thank you for explaining that! I get it now! I checked again and nowe all the plates were moving. But now my problem is that the clutch fluid goes out of that small hole on the resivor cap when I pull the lever In. Is that common?

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Sorry it was a bit long winded, but that's the principal. Anyway, no it shouldn't weep there at the lid as it has to be a sealed system to work. Have you checked the black rubber seal is seated correctly under the lid and in sound condition. Have you looked up the bore of the master cylinder piston to make sure there is no weep of fluid (where the lever push rod goes in - should be nice and dry). Take it you bled the system from the bottom with a syringe and used mineral fluid as opposed to brake fluid. You need all the air out and an airtight seal to get it to work properly.

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No the 125/150 had Magura clutches up to and including 2015 model year. Our 2016 125s are the first of the peashooters to get a Brembo system. Bob.

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I closed the hole with some silicone for now and it doesn't come out of there anymore. But the clutch still is not working. When you pull the level in it feels like it should work but then when you try to put it on gear it just stalls

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Okay, so I bled the clutch and it works. But if I try shifting into 1st from neutral it just grinds gears. I have to shift into second then 1st when I want to start driving

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