05 hard to start when warm

I just bought a 2005 yz250 with a rekluse and fww. It started up great when I went to buy it and for the first time when I rode it. I found the bike really hard to start when it was warm, I had to put my left foot on the stand to get it going.

I did notice a funny kind of "almost fire", accompanied with a puff of smoke on several attempts.

I have a 172 main and a 45 pilot in the bike now. Riding at around 5500 + altitude. It seems from the jetting charts that this is not far off.

I did notice that the reeds are not fully seated against the reed block, how imperative is it to not see any light between the reed block and the reed tips?

I did notice a slight bog when just taking off, but I ride mostly in the upper revs since I was at motocross tracks.

The guy I purchased it from was around 7000 feet.

Any suggestions?

Thanks in advance!

Sounds like you may need some new reeds... there should be NO gaps or chips/cracks. I had this exact issue. My first thought was an air leak, but after replacing the reeds I had no more issues.

How many hours on the top end? I would do a compression test while you are at it. Leakdown test would not be a bad idea either.

Edited by BDubb106

Unknown hours on the top end. I am thinking I will just order the parts since I have it torn down halfway already. Any recommendations on a brand? Namura? What size should I go for? It looks like the top end has never been apart judging by the head and cylinder nuts. No marks on them like a wrench has ever been put to them.

Also I noticed some spooge coming from my pv vent. I also noticed some black oily carbon stuff on the cases where the reeds go in. Is this normal?

Im not going to recommend a piston... it will just turn into a flame war. I will however say I have used Namura successfully and am currently running one in one of my 250's now, but Im a die hard Wiseco fan so that is all that goes in my race bike. Any piston will do just fine as long as clearances are correct. However it is a great idea to replace it since hours are unknown to save yourself the headache and possible money down the road. If you have a set of digital calipers you can measure the cylinder to find out what size piston you should get. Or you could take the cylinder to the shop and they will likely measure it for you free. Normally a C piston is a one size fits all.

Spooge from the PV vent is 100% normal... that is exactly what it supposed to do. Its nothing more than a vent/drain line. I get a few drips every now and then. As far as the reed mating surface, that is not normal at all. I would inspect that area very carefully.

Hope that helps a little.

Sounds to me like a worn reeds or a weak top end. Do a compression test, this will tell you the condition of the top end. Do some searching and reading under "compression test"

+ 1 on the reed. Try to flip them over firts, if it close the gap. If not change them its make all the difference to help,mine start. Bad reed is like being to rich on the pilot, it let more fuel to pass, that may cause your smoke.

Im not sur if stock reed can be flip. I run vf3. Maybe someone here know?

So I wanted to post up my results:

New top end + new reeds = 1 kick to start.

My off idle bog/ burble is also gone.

My new reeds still have a tiny gap between the reed cage and the reed edge, but it is significantly less. I went with boyeson power reeds. They are a different design from stock, but screw right on to the stock cage, eliminating the curved metal stopper that came stock.

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