I just bought a used KTM 525exc 2005. Sort of a beginner when it comes to dirt bike engine issues especially with a 4 stroke. The bike runs and rides okay but I have trouble starting it as it just has way too much compression, and some times I even feel like I'm chipping off kickstarter teeth. I'm not sure whether its the valves, decompressor, cam timing, or anything else it could possible be. Can someone please help me out as I'm really lost on what to do and local shops are quoting over $200 just to have a look!! I've tried tightening the intake and exhaust valves to see if it would make a difference and is barely noticeable.


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Yo, welcome.
A big 4T can be impossible to kick over if you havent started from TDC.
Otherwise it's all technique.

How did you tighten the valves?
Yeah I use that technique when starting...Even with the plug out it still has a similar compression with the plug in. So no idea what's going on!! I just mucked around with the valves to see if it would make a different but it isn't even noticeable. They were changed at TDC.
Messing around with the valves is not a good idea. They should be set to factory settings and left along. I am at a lost that it is hard to kick with the plug out. Should be smooth with no compression. I have a 2010 530 and you need to put some leg into it to light it up.
Yes I'm going to set them back to factory settings. After doing a bit of research the resistance without the plug might be from the starter motor engaging as I can hear after I give it a kick
I figured out its the starter that makes it more difficult and no its not wired up so the bike's just kick start...How would I go about hooking it up anyway?
I figured out its the starter that makes it more difficult and no its not wired up so the bike's just kick start...How would I go about hooking it up anyway?
When it to electricity, I am one dumb sonuvabitch. You need to get a manual. You can probably find a free download somewhere.
Could be hooked up but the fuse blown. When my 530 was getting a short and blowing the starter fuse, it was a bitch to kick start.
Just take a wire from the + terminal of the battery and then to the big lug on the starter. Damn thing should do something then. Make sure it ain’t in gear.
those older ktms aren’t a walk in the park to kickstart. Regardless of who you are. Mess with the valves unless they’re out of adjustment, and your messing entails putting them back into factory specified tolerances. Make sure you use the correct adjustment marks and are on the correct sequence of rotation (usually TDC On compression stroke and a couple marks to line up-outlined in service manual)
If you are not god damn sure that your on the correct marks and adjust the valves somehow, it may be really really hard to start, or not start at all.
modern 4 strokes should start within 2/3 kicks usually. For most of them, start with the bike cold as normal. Turn gas on. Give the throttle 2 quick cranks to wide open and close. Turn the choke on. Kick it through slowly, and listen to the motor. It’ll make a sound that’s similar to air escaping usually, that’s the exhaust valves opening and closing. After you hear that sound, keep slowly kicking until you feel that same feeling again. Now it’s on the compression stroke. Once there. Kick it from the top of the stroke, all the way through, with all your weight. It should start. If it’s always a massive pain to start, pull the carb off and take everything apart that you can, order rebuild kit, remove all the jets, slide, needle, so on so forth, and let it sit in a container full of carb cleaner overnight. Jets, carb body possible. Needle. Bowl. Float. So on so forth. there’s a lot of crap in today’s fuel that will gum a carb up. The passages in them jets are extremely small in some cases, make sure everything’s clear enough to see daylight through before assembly, and try to record things like adjustment of screws and cables before removing.
modern 4 strokes should start within a few kicks. Not a hundred every time. Some are a lot more temperamental than others, and most have a ritual. That’s what works for me. Good luck