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400 EXC valve train

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I am considering a new KTM 400 EXC. Do the valves on this guy move much once broken in assuming moderate trail riding conditions? I have heard it has the older screw type of adjusters as opposed to using shims. How much dissasembly is needed on one of these bikes to get the valves done properly?

Thanks.

Greg

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I don't think there will be any other bikes available that would be considered easier than a 400/450/525 when it comes to adjusting your valves with the exception of an XR 250/400.

I don't have alot of 4 stroke experience. My '06 400 is my first.

You'll need to remove the seat and tank for starters. If an adjustment is needed it seems easiest (for me) to remove the radiators and adjust away.

While this valvetrain isn't the most high tech, it is reliable and pretty easy to service.

I still think I'd rather just mix my gas and be done with it, but I'll get used to it I'm sure.

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KTM's require fairly frequent valve checks and adjustments, especially the intake valves. Most check them on about 30 hour intervals. The intake, but not the exhaust, valves tend to close up over time.

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KTM's require fairly frequent valve checks and adjustments, especially the intake valves. Most check them on about 30 hour intervals. The intake, but not the exhaust, valves tend to close up over time.

Really?

My old 02 400exc that is now a buddy bike has over 15k miles and the valves have been adjusted 3 times.

My 04 400exc was correct right from the factory and are still in spec. It has 4500 miles on it. I had to adjust my old xr400 much more often then that.

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I have not had the same luck as UD

I check mine about every three months

John is right, the actual adjust is not bad...it's getting too them thats rough.

Seat/tank easy

The earlier bikes '00-'02 needed to have the radiators removed

The newer bikes can be drained and bungied out of the way.

If a new bike, I'd check the valves at about 3 hours, then again around 20 hours

The BIG thing is to get a MOTION PRO feeler gauge...a regular feeler is tough to work around in there. MP feeler is about $4

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.....or use the '1/6 turn method' for adjusting valves.

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.....or use the '1/6 turn method' for adjusting valves.

I use that method but still check with the feeler gauge after just for good measure. :thumbsup:

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I will call BS on this one... 15 hours. Every 15 hours you need to check them. While you check them, might as well adjust them as it takes 1 minute longer to do that once you are in there. 15,000 miles? While I beleive you, I bet if you took the valves out you would find them in need of replacement.

The RFS bikes, if you get one with stainless valves, should last a long time. Dave Hopkins is THE GOD of KTM valves. My SX valves lasted 42 hours. But, there were other things that caused their demise...

THe EXC will last a long time if you keep it maintained. Valve adjustments are hard the first time you do it, after that, it is simple. You have to appreciate old technology as it has been around long enough that all the bugs are worked out and they are very reliable. Go with the EXC and love it. Just change your oil and air filters, and clean your oil screens religiously.... or else.....

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I will call BS on this one... 15 hours. Every 15 hours you need to check them. While you check them, might as well adjust them as it takes 1 minute longer to do that once you are in there. 15,000 miles? While I beleive you, I bet if you took the valves out you would find them in need of replacement.

Well that would really suck in Colorado. Adjust the valves every two or three days. If I had to do that I would dump the KTM in a flash.

If I were racing the bikes or running WFO that may be a good idea but I ride trails on these machines. Also I'm religious about the air filters and changing oil. I had an 03 450exc that the valves needed adjusting quite frequently. I replaced the valves and the adjustments became quite rare. The original valves were heavily cupped.

I'm leaving for Taylor Park Friday and I'll bet the valves will still be in proper adjustment when I get back. Probably the machine will have 5500 miles then.

I'm sorry yours haven't been as good as mine.

ps: The 02 has the original water pump, cam bolts, cam sprocket bolt and cam bearings. All items which everybody told me would quickly fail. :thumbsup:

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Luz- either you ride at 2000 RPM's or you have been REALLY REALLY lucky on valves!!! Good for you man!

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I'm going to pick up an 07 400xc-w. I really hope it will be as good as my last 3 400s.

ps: I don't race too often any more. When I do, I ride the 200. :thumbsup:

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I've posted a very thorough procedure with pics that's pinned on the valve adjustment section of KTMTalk. Fairly simple.

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Adjusting the valves on a KTM is a snap - you only have 4. Apparently you're all too young to have adjusted a solid lifter cam on a chevy v-8; or how about a hydraulic lifter cam while the engine is running?

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I'm leaving for Taylor Park Friday and I'll bet the valves will still be in proper adjustment when I get back. Probably the machine will have 5500 miles then.
Luz- either you ride at 2000 RPM's or you have been REALLY REALLY lucky on valves!!! Good for you man!

You should have bet me. I had to adjust the intakes 2 days after I got to Taylor. I called that one wrong. :thumbsup:

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I still have a couple feeler gauges in my tool box that are beat to death from adjusting Chev V8 while running. Oil running down the headers, smoke everywhere, what a mess! :thumbsup: Whos idea was that that the engine needed to be running?

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I still have a couple feeler gauges in my tool box that are beat to death from adjusting Chev V8 while running. Oil running down the headers, smoke everywhere, what a mess! :applause: Whos idea was that that the engine needed to be running?

I adjusted the valves a long time ago on my then girlfriend's old Opel station wagon, which you had to do with the valve cover off and the engine running too! :thumbsup: Did it once and told her that I would never due that again! :ride:

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