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Hard to turn motor over-KTM 450 EXC

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Here is a strange one: doing the valve adjustment on the 2003 450 EXC.  Took the spark plug out, to try to find TDC.  I can barely turn the motor over!  It's really hard.  As in, I'm lifting the rear wheel off the bottle jack, while trying to turn the motor over.  

 

So, I pulled the right side (clutch) cover, and I can see the starter is turning over with the motor.  So, I slipped out the gear that joins the starter to the clutch basket.  Once I did that, it turns over like I expect it to.  

 

Does anyone think this is odd?  I don't even know there is anything wrong, but it doesn't seem right...  

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Here is a strange one: doing the valve adjustment on the 2003 450 EXC.  Took the spark plug out, to try to find TDC.  I can barely turn the motor over!  It's really hard.  As in, I'm lifting the rear wheel off the bottle jack, while trying to turn the motor over.  

 

So, I pulled the right side (clutch) cover, and I can see the starter is turning over with the motor.  So, I slipped out the gear that joins the starter to the clutch basket.  Once I did that, it turns over like I expect it to.  

 

Does anyone think this is odd?  I don't even know there is anything wrong, but it doesn't seem right...  

Only your method is odd :devil: ,  spark plug out, put in 6th gear and bump the rear wheel around(off the ground of course)..

 

The bikes have a lot of compression

Edited by Spud786

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I've never removed the plug to turn it over. A lot of the resistance you feel is the heavy valve springs. Providing the ADC is operating properly , you are should only get about 115psi. If the exhaust valves are tight the ADC will not function properly making it harder than normal to turn over.

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Thank you for the replies.  

 

But I don't think either your replies explain what I'm seeing.

 

With the spark plug out, they don't have any compression.  So that's not the issue.

 

The difficulty in turning the motor over went away when I pulled the idler gear (or whatever it's called, under the clutch side engine cover, that connects the starter to the clutch basket).  So it's not the valve springs I'm feeling.  

 

What's making the motor difficult to turn over is the starter itself.  I'm attempting to turn the rear tire, with the bike in gear, and the resistance is just ridiculous.  As in, I can pick the bike up off the bottle jack that is holding the wheel in the air, just by applying upward force on the rear wheel, while attempting to turn it.  

 

Take the starter out of the picture (by slipping that gear out), and the motor turns over like any motor should.  

 

Does anyone think that's odd?  Or is that normal?  

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I'll reword my reply, even with the spark plug out and in 6th gear , there is still a lot of resistance to turn the motor over.  You cant just push the wheel forward easily it has to be kind of bumped around.

 

As to the starter gear, maybe it does have some effect also, but if you have no running issue, I wouldn't worry about it.

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Ok, thanks guys.  No running issue that I'm aware of.  This is my son's commuter bike.  Just thought it was strange how hard the motor was to turn over.  

 

Starter spins along with the gearing in both directions.  But perhaps this is down to the 50 weight oil and 40+ degree temps in the shop.  

 

Really, no kidding, if you slip that gear out, the smaller of the 2 numbered "14" , and the motor turns over as easily as a 50cc moped!  

 

I suppose it's down to the design of the bendix.  Thanks for the input.  

 

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If the starter motor spins in BOTH directions, #13 has siezed.  However, if this was the case, I doubt the engine would run, as it would be trying to spin the starter at ridiculously high rpm all the time.

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