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Are these power valves wrong? (with pics) 09' KTM 300 with no top end power


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Hi guys, new bike, new forum 😛 I have finally worked my way up to a 2009 KTM 300 after many KDX200's, KTM 200's, 125's and a CRF450X.
 
So! I love the bike. BUT, it's not revving out, it's still great to ride, does everything I want it, the bottom end power seems incredible. However, when you get up in the rev range it just flattens out and makes the top end power of a 125 2-stroke if that.
 
So, I took the right side cover off, revved the bike, power-valve is actuating correctly. I took the expansion pipe off and didn't see what I was expecting (see pics). The power-valves appear half close at rest, and when moving the gear under the right side cover, they open up. It is my understanding that this would mean that I should be missing the bottom end power, and have full top end.
 
Can anyone confirm that the power valves are in-correctly time as it appears? Would they be impacting my top-end power as they are?
 
If not, what can I try next? Bike has yellow power-valve spring turned in slightly but it's as if the bike isn't revving properly.
 
Also, FYI, bike has good compression, 10 hours on top and bottom end, FMF Gnarly and Powercore 2. Stock jetting (wanting to get everything else right before I tinker with that).

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Can you get a pic of how the pv gears on the left/right side of the cylinder are lined up?  There are some (very faint) dimples on the gears that need to be aligned. Also make sure #6, #5 aren't reversed.  Dimples are on #2/6 and 5/17....

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Edited by Dirt Addict
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The Z-Dimension is critical.  Once everything is aligned, make sure that item is spot on.  It will effect the engine power dramatically.

 

Harbor Freight sells a cheap calliper.  Buy 1 and tape it permanent to the correct dimension.  You'll be that farther along on your next top end.  👍

Edited by superslyko
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Thanks for all the replies!!

I'll take left/right covers off and re-check.

I'm led to believe the guy that owned this bike before me didn't know how to mix fuel properly, it was running VERY oily. I drained the fuel out of it and I run silkolene DIRT at 40:1 mostly (has ran through one tank since I got the bike). Also occasionally use motul 800 or panolin.

I've timed powervalves on many a 200's before (older models though). It was just not what I was expecting as the bottom end felt fine, man I will be in for some torque when I sort out the timing!

I'll post back later after I tear into it. Have also replaced fork seals and re-wired lights and indicators to have quick release plugs as the first jump I went over I moulded my number plate to the rear wheel 😛

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So, the problem was that they had been installed the wrong way around. The left powervalve clearly says L on it, but I guess someone missed that. Anyway, they're in and it all looks to be working properly now. I'll take it for a ride in the morning to test the difference and see if I have my top end power 🙂

On a side note, MAN these KTM's are easy to work on. Everything was obvious so far as power valve timing goes, very simple. The most I've had to do with power valves was on my old KDX200's

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I had 3 KDX200's, all 3 of them had broken powervalve actuating linkages, one of them had seized/broken/missing power valves when I got it. You had to remove the cylinder to access them and there was a semi-complex sequence of timing marks and a fitting order to get it right. One of the KDX's had a piece of the power-valve system about the size of a 5c piece that had been welded back together by a past owner. And another one I had, the same bit broke and jammed in between my case and shift-drum ending in a crankcase split. KTM has done well.


Test rode the 300 with it's now working power-valves..... it now rides like a 300 instead of a 200 like it did before. If anyone wants to decrease bottom end by 30% and cut there top end in half, swap there power valves around 😛

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