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Greeting from a TW200 newbie.
I have a 2006 TW with only 1700 miles that runs great. But after riding for a while and shutting off it is very hard starting after sitting for 20-30 minutes. Starter just cranks; choke, no choke, it doesn't matter. If I hold throttle wide open and continue cranking it sputters and will eventually, reluctantly, come back to life and then run fine. I suspect some type of a vapor lock issue but have not seen any similar problems from fellow TW owners. Next time it happens I am going to open the gas cap and see if there is a venting issue but in the meantime I thought I would see if anybody has additional suggestions. Thanks Much
 

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When shut off, is the petcock also shut off?
If not and if float valve is leaking, it may be flooding.

When it will not start right away, pull plug to see if it is wet.

If this is the cause, then cleaning carb should be done and oil changed, as it is likely dilluted with fuel

...and welcome to the forum.
 

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BTW, vapor lock occurs when fuel vaporizes on the inlet side of a fuel pump, typical with an engine mounted mechanical pump.
In the seventies, this was mitigated by recirculating unused fuel.
With tank mounted electric pumps, pushing fuel, this is not a common issue, even in very hot weather.

For a gravity flow system, this should not be a concern.
 

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If you need to hold WOT for a while before it sputters to life it sounds like it's flooding out. Most likely from a leaking float valve.

The way to diagnose this would be to turn the petcock off maybe 30 seconds before shutting the engine off. This should use up the fuel in the line and isolate the tank so there is no head pressure "pushing" fuel against the valve, and thus potentially into the engine's intake side.

Let it sit for 20 minutes or whatever and then go to restart it. If it starts easily, you found the problem. Replace float needle. I'm fairly sure this will be the case.
 

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Discussion Starter #6
Thanks SportsterDoc. Hoping the float valve isn't leaking. I always shut the petcock off as soon as I shut the bike off. It has a fresh oil change. Oil level is right where it needs to be and there is no gas smell in the oil. I will try pulling the plug next time to give it a look...THANKS
 

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With the petcock shut off, leakage past the float valve would be limited to what is in the fuel line, assuming the petcock shuts off completely.

Although this is not the only possibility, it is probably the most likely.

Excellent suggestion from RaZed1 re shutting off petcock early, although needle may be OK, if the issue is debris.
 

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If I hold throttle wide open and continue cranking it sputters and will eventually, reluctantly, come back to life and then run fine.
There is also the possibility your mixture is just set too rich, which could make starting cold not an issue but hot starts, a problem. If you aren't shutting off the petcock every time you're done riding, I wouldn't suspect the float valve as the problem as it would still be an issue even on cold starts. If you do always shut it off, then the float valve is suspect. I know a lot of folks tend to think a cold engine doesn't need choke, but unless it hot as heck outside and the bike has been sitting in the sun, you really should have to use it if only for a few moments on the initial startup. If it turns out the float valve doesn't seem to be the issue, check your mixture setting while the engine is hot and adjust your idle RPMs to stay between 1300-1500 (I tend to run toward the 1400-1500 side of it). Adjusting the mixture will make this drift along with it, and especially on a smaller engine, correcting the mixture if it is too rich or lean tends to move idle RPMs out of specs. Hope you figure it out!
 

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Good suggestions re mixture, but float valve would not be eliminated from cold starts, as fuel in the line from petcock to carb may drain then dissipate during cool-down
 

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Greeting from a TW200 newbie.
I have a 2006 TW with only 1700 miles that runs great. But after riding for a while and shutting off it is very hard starting after sitting for 20-30 minutes. Starter just cranks; choke, no choke, it doesn't matter. If I hold throttle wide open and continue cranking it sputters and will eventually, reluctantly, come back to life and then run fine. I suspect some type of a vapor lock issue but have not seen any similar problems from fellow TW owners. Next time it happens I am going to open the gas cap and see if there is a venting issue but in the meantime I thought I would see if anybody has additional suggestions. Thanks Much
Bike sitting for 30 minutes is not hot anymore. Try half choke (or none) and no throttle depending on any carb changes (if any) from stock.
 

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Might just be crap gas....bikes/carbs don't like ethanol gas, especially in hot weather. I avoid any ethanol for my bike, lawnmower etc. Ethanol in gas causes it to boil really easy in hot weather.
 

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Following the advice in this thread. Earlier this week, ride characteristics and plug chop on my bike indicated a lean condition. Knew the carb was dirty - gave it a clean and now I'm experiencing what seems to be a rich condition, similar to yours. As others have said, try not to flood the thing with desperate throttling (guilty of that on occasion myself) and try to isolate the solution, adjusting one thing at a time. Let us know what the culprit was once you figure it out.
 
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