2009 Tank 250 Touring will not start!!

[ebay4now]

Ok, so after browsing what seemed like thousands of threads and trying everything, I still can't start this thing. History is this. Bought this scoot new and it never did run right. Very rough idle and had a terrible time starting. Most times could not get far from the house without it stalling and having to push it back. I rode it to school the other night and the same thing, stalled and did not restart.

It will spin the starter just fine and at one point I could get it to run for a few seconds on carb cleaner, now nothing. I have lined up both timing marks and adjusted the valves to .004 intake and .005 exhaust. Cleaned the devil out of the carb including all the jets and so forth. Had previoulsy installed one of the those little 4psi electric fuel pumps with a regulator set at 1 and still nothing. Take the plug out and ground it and crank it over and it has a pretty bright blueish white spark. Seems like it is getting fuel as the plug is a little wet when I pull it out after cranking it.

It sounds like it wants to start, but just kind of sounds like a backfire through the carb. I have all the air cleaner housing and hose off the bike so it is just the open carb. Even went as far as hooking up my timing light and checked it against the inspection hole while cranking it and it lit up the notches every time.

I am at a loss.... Any ideas???

[gatekeeper]

Need to put the air filter box/filter/hose back on and make sure there are no air leaks in the intake system. Without the air box on you will be way to lean. Make sure the fuel/air mixture screw is set properly. Turn it all the way in (clockwise) until it seats (gently) then turn it out (counter-clockwise) to 2 1/2 turns to start with.

Backfiring thru the carb may mean the intake valve is too tight or is just not seating properly. Double check the valve gaps. The measurements you list are good and are in inches. If you set them to millimeters they are way too tight.

Hope this helps.

[imnts2]

Have you done a compression test?

[ebay4now]

Ok, so after a long day messing with this thing I feel like I am really no further along. I was able to get it to actually start and it idled perfect, then it shut down and would not start again. I hadn't done anything at that point except double check the valve adjustment. I put the air box all back on and it made no difference. Also have done a compression test and it has excellent compression (over 125psi, but my guage is not the greatest). But you absolutely cannot hold your finger on the spark plug hole when cranking as it will blow it right off.

Went through the carburetor again and cleaned it out real good. By the way, I forgot to mention that this scoot only has like 384 miles on it. I have hardly ridden it in the 2 years I have had it. Changed out the fuel with fresh, new plug.

I notice that if I let it sit for a few hours with the spark plug out and then go put it back in and try it I can get it to start. Not easily, but it will start and idle to 2000 rpm then quit after a minute or so. Then not start again.

Any ideas???

[wile]

The Pilot Jet and or Passage is CLOGGED that is why it will only run when cold. WHEN COLD it is running OFF the ENRICHER(CHOKE) once the ENRICHER shuts off the extra fuel it dies.
Take the carb off and Get a SPRAY CARB CLEANER they come with a long thin straw to get into small holes.
Now take the Pilot jet out and YOU SHOULD be able to see DAYLIGHT through it, IF NOT it is clogged and you may need a fine wire to get in there and clean it out. Then with the pilot jet out Stick the Thin Straw into the hole and spray.
Wile
Here is where the SPRAY SHOULD COME OUT BY THE BUTTERFLY when you spary into the PILOT JET HOLE:
The holes are TINEY so any VARNISH they will be clogged.


Here is where the SPRAY SHOULD COME OUT BY THE NEEDLE GUIDE when you spray into the MAIN JET HOLE:

[wile]

Also since you have the carb out, turn the FUEL RATIO SCREW CLOCKWISE until it stops and then turn it out 2 1/2 Counter CLockwise. That should be enough for it to run pretty good you can always fine tune it if need be.
Wile

[ebay4now]

So, I have been offline for awhile trying to fix this scooter and finally did it!

I took the head off once and lapped the valves and cleaned everything. The valves seemed straight and all, not bent or warped but I noticed that the valves seemed to be pretty sub-par to most I have seen before. I put them back in anyways and crossed my fingers.

It ran ok for a day or so, but it was still kind of hard to start. I had gone through the carb many times making sure it was all clean. Then I was driving the scooter on a test drive a few miles from my house after it had gotten warmed up and it quit again. Valve clearances were fine, but it kept popping through the carb.

I could take the carb off the intake boot and watch the valve go up and down and watch the compression push by the valve with every stroke. I knew something was wrong with these valves.

I ordered a brand new head and valves and put it on tonight. Guess what?? It started on the first try and maybe spun over twice before it caught and idled smooth as silk. It has never ran this good before. The new head was much nicer than the other and the valves looked to be much stronger and machined better.

So what was happening all along was that the valves were warping when they got hot and causing low compression, equalling no starting! Hard to believe that with only 362 miles on this scoot that this would have happened. But it did appear that maybe this head was not the original one on this engine. It looked much more used than the rest of it. Maybe the dealer swapped it onto another scoot before me? Who knows, it is fixed now so I don't care.

Thanks for all the tips, they did help me get in the right direction. And now my carb is as clean as they come!

[wile]

FANTASTIC!! Good job of diagnoseing and not giving up. Also thank you for coming back and letting everyone know what the problem was and the fix. What you encountered is a new problem that can cause hard starting and acta as if no gas is getting fed after a little warm up even with the valves being adjusted. You were the Science Project on this one and you found the problem.
Again Great Job
Ride Safe
Wile

[gatekeeper]

Great to hear you're up and running! Thanks for letting us know what it took to get it going.