did this last year and had a valve job done, shop said its the valves, so new valves and seats, still hard to start but ran good for 200 mi. and it sat for a week and no compression again, could it be valve guides, was hard to start hot let it sit 10-15 min. and it would start and run good, set at TDC, took out plug, put tissue paper over muffler out let, air box intake and crank case breather, blow compressed in plug hole, paper over air box moved a little, paper over muffler outlet flapped like crazy, gave it 100 psi and air box stopped, muffler went crazy. valves holding open, also if u tow start it starts right up,

 

Would help to know what machine you have.. I see you posted in the Honda section also.

 

hopen u would look, its realy a Suzuki dr350s but no relpys on that page,

valves checked before test and still were set correct, TDC for sure, also turned crank 360 4 times to make sure and lined up tdc mark on crank every test, stuck long screw driver in plug hole to find tdc also, watched valves open and close and made sure they were loose when testin, even back off valve adj. 1/4 to make sure they weren't holdin valves open, this is a buddy of mines bike he's had in the shop and they did a valve job and he can't afford any more shop jobs, also I put a new cdi in that Chinese crap and it sparked and the kill stopped the spark and gased it up and now no spark again, can a cdi or stator burn out that fast or is it my bad luck. thanks for the help.

 

You don't mix electrical components from one machine to another!The answer is yes,it can burn out other components!! If you're going to do your own work you need a good shop manual if you don't already have one. If it's a Chinese knock off of a Suzuki machine,then that's another story also..

 

no two different bikes, head is a dirt bike but no body has any Suzukis any more, atleast no response on other site, tring here to just get some ideas as to whats up with that valve job, cdi got a new one 5 pin for Chinese junk and it didn't last 20 sec., your 100% correct, never swap brands, never put any Chinese crap on a good jap bike.


don't let friends drive Chinese.