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[boxbiker]

see my other post about trouble keeping my tr4 running.

after i reset the floats and recentered the jets i cranked it again. as long as the choke is on i can rev the motor and the carb pistons rise and fall normally. as soon as i release the choke it acts like it runs out of gas and no matter how i play with the throttle it slowly dies. i can see fuel in the clear line so i know there is gas to the carbs.

[motomadness1947]

okay,  if the strombergs are anything like the SU's    When you pull out the chock (increase the chock) it lowers the jets which increases the amount of gas to air mixture.  american carbs keep the gas the same and reduce the air by way of a flapper valve witch does the same thing it increases the gas to air mixture.  If your tr4 runs well or at least responds well to the reving of the throttle with the chock on. it is telling you that the gas to air mixture is good.  ERGO   (you knew that was coming) with the chock off your  gas to air mixture is to little.  SO you need to increase the gas to air mixture by increasing the amount of gas present ofr the amount of air.  If you can make sure that the needles that go up and down with the piston are at the correct hight.  On SUs this is done by making sure the needle neck that goes into the piston is perfectly level with the piston.    Just for the fun of it move your needles up into the piston by about 1/8th of an inch and see what happens.  if it helps cure the problem one of two thing is happening   number 1 you have an air leak around a gasket or through the throttle linkage or number 2 your needles are the wrong size (this is very doubtful as they work well before.  my bet is you have an air leak.  Try moving the needles as above and let us know what happens. 
Bruce Fahnestock   615-294-4238

[TomMull]

I'm beginning to wonder if your issue is the carburetors. If it runs with the chokes, you know the chokes are working and you're sure the floats are not way too low. The only other cause of lean condition (to my knowledge) is a restriction in the fuel line, fuel pump or in the carburetors themselves. I think you said that you were getting a good flow from the pump. I know Charlie Fitch suggested you check the fuel bowl filter and screen and I think you said you did all that. Here are a couple more shots in the dark: Have you run the car up to temperature? It may take quite a while under choke. Any chance you could have a bit of water in the tank? Old tanks do cause problems particularly with ethanol gas. Low compression could also cause similar symptoms. Weak spark too. Sorry nothing more specific. Tom 
Tom

[boxbiker]

Thanx to everyone who read and responded. I am not an expert on strombergs or SUs as I have spent the last 20 years working on bikes and am familiar with dellortos and amals so I'm thinking with that mind set.

The strombergs have a flapper that restricts air flow, it does not lower the jet. The needle is secured by a set screw so is not adjustable. I have removed the pump and filter and checked the filter and it was clear. I have completely drained the tank by removing the outlet on the tank and flushing it with fresh gas. I put a section of clear bike gas line where the line connects to the carbs so I can see that there is gas at all times. I have put new mounting gaskets. I have run it long enough to bring it up to running temp.