Cam chain ajustment - 2011 Derbi Terra 125

Well first u need to remove the top cover and get to the cam. Remove the two bolts holding the cam sprocket and turn the engine till its at the tdc mark on the alternator rotor.on the sprocket there should be two notches. These have to line up with the top surface of the head. Ie one of the bolts is up one down. Put the head cover back on and ur timing is set. Then if it is anything like my xl250s on the back rhs of the head there should be two bolts. The one at the top is a 10 mm bolt the one at the bottom is a 10mm nut. These adjust the cam chain tension. Start the bike. Warm it up and while idleing loosen both off NO MORE than TWO turns. Tighten them back up and there is your chain tension done. If it slips u prob need a new cam chain.

you don't, its self adjusting, if it feels slack you prob need a new chain or guides.

It can't be adjusted, it's self adjusting with a tentioner. If it makes too much noise, replace the chain and don't forget the guides and tensioner!

Just loosen the tensioner bolt then re-tighten. The tensioner assembly is on the back of the cylinder. Please rate my answer. Thanks!

Your XT has a self adjusting cam chain tensioner and needs no attention unless it has broken.

Cam chain normally must be replaced, but sometimes cam chain tensioner may have some space to put more tension to tighten the cam chain. If you know how to access it then go for it. Good advise?

I don't know that exact model but all cam chain tensioners are automatic these days & have been for over 20 years

Hope this helps (if so please mark as helpful !!)
Ride safe
Bike-Doc

did u hav piston @tdc power stroke-valves shud slightly clic with ur hand after ajust-mite hav performed it at exhaust stroke! let me know

theres a cam chain tensioner in the rear of the cylinders-u need an ajustable rench or other-most important is purchase a clymer manual at bookstore or online-these ar detailed books on any problem for your kawa-viva tokyo

The problem is valve timming, recheck the valve timming. Hope this helps!