95' RM 125 hot no-start

[hawaiianrm]

     

Aloha all! new to this forum so here goes. have a 95 rm 125 that starts first kick when cold but after riding it for a while won't restart w/the choke on or off. just rebuilt the top half with a new cylinder & wossner piston/ring, new pin, bearing, clips & new gasket set. cylinder & head torqued to specs. running non-ethanol fuel mixed 32:1 w/motul 800 premix oil.
bike starts & runs great when cold but can't get it to start after riding for awhile & shut it off. was real careful on the break-in to seat the ring-compression is @ 165 & the pwk carb has been overhauled & cleaned, float level height set. coil tests within value range according to manual & i get a good spark. bike will start if i bump start it when hot.
Any & all suggestions appreciated. Mahalo in advance for all replies.
Peace

[PawPaw]

Do a compression test when it is hot to see if it's dropping off and causing the hard start issue. Also may want to pull the exhaust pipe and look up into the exhaust port at the piston to see if there is any scoring as the ring may be sticking when hot and then releasing when cold.

Paw Paw

[gusco]

Any signs of running rich? Bikes like to start up rich when they're cold, but leaner than that once they're warm.

[hawaiianrm]

pawpaw/cusco,
Mahalo for the reply. compression is @ 165 & plug is a little oily but not alot. Took off the exhaust & intake (reed cage) cylinder/ring looks normal. Bike has the v3 reed set up & the corner of one reed is chipped just a little & when I back light the cage I can see some light coming thru the reeds & cage tho not a lot. A couple of the reeds look like its delaminating(?) when held up to the light. Since I'm new to the site I can't load pics yet lol.
Some history on the bike: I just recently picked it up, non-running. Original (I think) piston split the ring & gouged the cylinder pretty deep. I didn't want to re-sleeve it w/an la sleeve so I opted for a new cylinder & a Wossner piston/ring/pin/clips & Cometic(sp) top half gasket set. Tore the entire bike down to the frame as po or somebody thought the frame was aluminum & tried to strip/sand it & then just can sprayed it black. So I media blasted it & sprayed it with urethane primer & some ppg 2 stage black I had from a paint job I did for a friend.
Replaced all the bearings (steering/swingarm/wheels/etc) & finished the hack job polishing of the swingarm/covers/etc from the po or whoever. refinished all the plastics (gonna replace them soon) cleaned & overhauled the carb, new air filter, plug, plug cap & coil (the og one tested close to the value limit in the manual.) Cleaned the exhaust power valve assembly & reinstalled in new cylinder w/a new clip from the pushrod to the linkage. Lubed the valve assembly, piston & cylinder with Motul 800. Changed the trans oil & am waiting on a new clutch plate/springs/gasket/cable set to arrive as the clutch is out of adjustment at the lever & the bike doesn't completely disengage when coming to a stop now that I have it running. flushed & replaced the brake fluid front & rear as well.

[hawaiianrm]

thanks for the replies. changed the reeds & its all good now. mahalo!

[Carytowncat]

Cool! Anyone explain why bad reeds would make a hard hot start ?