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1971 honda 750

Jn1972

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Hi new to this forum ,I just bought a 1971 750 # 2 cylinder is not firing any advice on where to start figuring out what the problem is ,the bike has 42000 miles maybe ready for a top end thanks jerry
 
Check compression, then do all the tune up items if engine is mechanically sound. adjust valves, adjust timing chain, replace points or file and adjust, set timing and dwell, sync the carbs. replace spark plugs.
 
I checked compression #1 is 155;#2is 155,#3 is135;#4 is 145 ,not sure but I think compression is ok ,I filed the points ,changed the plugs but # 2 is still not firing . have good spark on # 2 when out of bike.if I run it for a little while the pull # 2 plug it is wet so I think I am getting fuel any ideas where I should look next thanks for your help jerry
 
I tried it again today # 2 is not getting fuel,I pulled the bowl off carb # 2 and it was empty ,I can see the needle moving and the float but it does not get any fuel ,I can blow thru the fuel line but it seems with the bowl on it does not get any fuel any ideas what to check next thanks jerry
 
check the bowl vents. If you leave the bowl off and turn the fuel on does it flow out the needle?
 
Not sure where the bowl vent is on the carb,looked on the diagram but the vent is not marked
 
Between carb 1 and 2 and 3 and 4 there is a short black hose connecting the carbs together. Then on the inside of carb 2 and 3 there is a 90deg nipple that is supposed to have a hose which is your bowl vents.
 
Had a chance to work on 750 today ,I checked the bowl vents and they are all in place ,thanks for the help finding them , the fuel flows freely on #2 with the bowl off,I then tried switching the bowls between #1 and#2 no change after I run the bike bowl #1 is about 3/4 full and # 2 has just a little bit of fuel in the bottom,I tried removing the bowl vent hose between 2and 3 but that did not change anything .if you have any other ideas to try I would be great full thanks jerry
 
You have to make sure the vent passage in the carb body is actually open. The hose can be open but still be plugged in the body passage that goes to the bowl area.
 
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