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Just got done doing complete rebuild on motor. New valve train and had head cut for seats. All parts are oem. Have checked the timing 6 times and it's right. Heat cycled for break In. I took it out Friday for about an hour, ran fine no issues. Went to take it out for a ride today and it's giving me an issue starting, it'll start but it's taking a few more kicks than before, and when I do get it to run it has next to no power. I'm thinking it's the valves settling into the seats but I want to make sure it's not something else before I pull this thing apart again.

Welcome to CRF's Only!

You should definitely check the valve clearance as well as the timing. Verify the cam chain tensioner is functional and engaged. Check fluids (engine oil and coolant) for level and color. Pull the oil filter (lay it over to pull the cover without having to drain the oil) and inspect for metal shavings. Check ignition coil and spark plug. Verify spark. Verify fuel is flowing to float bowl last (after you verify spark and only in a well ventilated area and with proper precautions to avoid fuel spilling or igniting).

Good luck!

Ken

New cam chain, tensioner, I'm starting to think it's the valves settling into the new seats. Haven't checked then yet, was tinkering before work.

If the clearance was set correctly and the seats professionally and correctly cut they should not move enough to take them significantly out of clearance. When you are in there I recommend verifying the cotters/keepers are correct set.

After checking, double checking and triple checking every thing, I found a tear in the boot from the Air box to the carb, plastic welded it, runs like a champ again. New intake on the way. Was only about a 2" tear, can't believe that it caused it to fall on its face like it did lol

Good to hear you found the cause and it was an easy fix.

Ken