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2005 KTM 450 EXC shifting issues. I'm baffled.

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I've been searching for days on this issue, and I can't find anything that helps; that being said, I figured it was time to create an account and ask y'all for help.

 

I've got a 2005 KTM 450 EXC that I just picked up about a month ago; I've had KTM 2-strokes before, but never anything like this. Everything I read led me to pick the RFS years because of reliability.

 

My first few rides were uneventful with the exception of the clutch slipping a bit. I ordered a Tusk competition series clutch with heavy-duty springs and a gasket and proceeded to go to work. The install went smoothly and was as straightforward as any clutch I had ever done. (Note for later: I did soak the friction plates in oil before install.)

 

Since I sealed the gasket with red rtv, I left it dry overnight so the stuff would set. Well, I covered the bike with a tarp and didn't think anything of it. That night, we had a storm that blew a branch off a tree beside my driveway--nothing big, but it landed on the bike in such a way that it was depressing the electric start button. I was awake when it happened, heard it, and ran outside with my AR thinking I was going to get to plug a bike thief.

 

The next day, I filled the bike with oil (Yamalube full synthetic 15w50, midway up the glass). I cleaned both screens and replaced a filter just for good measure. The bike starts and isles just fine, but when I went to shift, I get gears grinding!

 

I thought maybe the friction plates were just thicker than the worn ones and that maybe the slave cylinder wasn't pushing them far enough apart. SO, I went ahead and bled the clutch lever assembly with tektro mineral oil just to cover all my bases.

 

If there's no load on the engine, I can shift between all six gears just fine if I feather the shifter. If there's a load or I shift farther UP than that "sweet spot," though, I get grinding. It's like the shifter is overshooting the single shift up and trying to grab another gear. What the hell?!

 

The ONLY other thing I did was change the front sprocket from a 13T to a 15T, but I can't imagine that having anything to do with it. Does anybody have any suggestions? Did I get the ONLY RFS bike not worth having? I'm scratching my head here and I can't come up with a damn thing.

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check your shift lever grinding on the new 15 tooth sprocket and chain, that's probably what it is.  Ive had it happen myself moving the shift lever, the 15 has just enough room so lever placement is more critical.

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check your shift lever grinding on the new 15 tooth sprocket and chain, that's probably what it is.  Ive had it happen myself moving the shift lever, the 15 has just enough room so lever placement is more critical.



...I hadn't even considered that. I'll check when I get back to the house this evening and report back!

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On 6/12/2017 at 10:55 AM, CFD338 said:

Since I sealed the gasket with red rtv, I left it dry overnight so the stuff would set.

 

Not sure that this is a good idea.  IIRC there is a small hole in the cover that feeds oil to the crank.  The crank isn't going to live long if it is plugged with RTV.

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Not sure that this is a good idea.  IIRC there is a small hole in the cover that feeds oil to the crank.  The crank isn't going to live long if it is plugged with RTV.


...I don't follow. I sealed the gasket with rtv, same as I seal every gasket I install (both sides of the paper gasket for the outer cover). What hole are you talking about?

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15 minutes ago, CFD338 said:

 


...I don't follow. I sealed the gasket with rtv, same as I seal every gasket I install (both sides of the paper gasket for the outer cover). What hole are you talking about?

 

05590308.gif

I think it's the small hole just above the hole marked "52" on the far LH end of the gasket (the hole closest to the front of the engine).

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05590308.gif
I think it's the small hole just above the hole marked "52" on the far LH end of the gasket (the hole closest to the front of the engine).


This is my first RFS engine; any idea how I might check? I can't seem to find anything of any value searching the ol' interwebs.

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05590308.gif

I think it's the small hole just above the hole marked "52" on the far LH end of the gasket (the hole closest to the front of the engine).

 

IMG_8864.JPG

 

We are talking about the top hole here, yes?

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31 minutes ago, CFD338 said:

 

IMG_8864.JPG

 

We are talking about the top hole here, yes?

Yes.

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Yeah, gaskets don't get RTV, knucklehead....that's why there's a friggin gasket.  

 

And, yes.  you now get to redo your work to ensure that oil passage is clear.  New gasket, and NO rtv.  I do like to wet the gasket with oil or greash, to help it not stick to the cover come time to remove

Also, you've got a hydraulic clutch which (within reason) will completely compensate for any change in thickness of the clutch.  I would bet that (if the shifter didn't fix it!  But it was shifting fine before with the lever in that position, right?  if so it's NOT the lever that's messing with you...) the clutch is just sticking together slightly and preventing you from getting into gear.  Pull the lever all the way to the bar and let it idle for a minute or two, then give the lever a good solid press down into first.  Don't stomp it, but be firm.  The lever position would only effect you going into 2-3-4-5 anyway, ie. upshifting.

 

Edited by bikedude987
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Yeah, gaskets don't get RTV, knucklehead....that's why there's a friggin gasket.  
 
And, yes.  you now get to redo your work to ensure that oil passage is clear.  New gasket, and NO rtv.  I do like to wet the gasket with oil or greash, to help it not stick to the cover come time to remove
Also, you've got a hydraulic clutch which (within reason) will completely compensate for any change in thickness of the clutch.  I would bet that (if the shifter didn't fix it!  But it was shifting fine before with the lever in that position, right?  if so it's NOT the lever that's messing with you...) the clutch is just sticking together slightly and preventing you from getting into gear.  Pull the lever all the way to the bar and let it idle for a minute or two, then give the lever a good solid press down into first.  Don't stomp it, but be firm.  The lever position would only effect you going into 2-3-4-5 anyway, ie. upshifting.
 


Yeah, lesson learned with the RTV on a KTM; that's the way I was taught, and my teacher has been building engines for 40+ years...I digress. I have a new gasket on the way.

The grinding wasn't coming from the clutch after all; I soaked the friction plates in oil before installing them to prevent them from grabbing, and I also bled the slave cylinder/clutch lever assembly.

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Did you measure the clutch friction plates?  I have heard lots of horror stories of aftermarket plates not being the correct thickness.  There are a couple different plate thicknesses made depending on year.

But.....If your pack is too thick you wouldn't be able to release the clutch and if it's too thin it would slip.  Either way, you transmission should shift without grinding without even using the clutch.  Dirt bike transmissions shift just fine without the clutch.

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