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Discussion Starter #1
so now after figuring out that i had a faulty plug. i went ahead and replaced the worn needle valves in my vm28 mikunis. got the leaking to stop. now i can't get the damn bike to start for the life of me. i've been at it all damn day and im about reaching my boiling point. i went ahead and turned to my trusty hanynes manual and proceeded to change the condenser and both sets of points. done. now check to see if she'll start. nope.
so im thinking that i don't have any spark...perhaps i didn't set the points gap correctly. re-did that. pulled the plugs and kicked her over. i shocked the hell out of myself by accidentally touching the left plug. definately have spark. now...i put both plugs back in and kick her over again. nothing. i proceeded to check and recheck everything 10xs over and over and over again. nothing. i have no clue why the hell the damn thing wont start. it's got fuel. its got spark. what the hell is left? please...help me keep my sanity.

hely

74 Yamaha RD350 cafe
 

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4 things to check
1) fuel
2) air
3) compression
4) spark at the right time

Double check that you have spark on both plugs. What are your air screws set to? Should be around 1.5 turns out from GENTLY seated.
 

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Discussion Starter #4
i thought i might not be getting any fuel so i left the tap on while i went to work. i came home and found a few drips of fuel on the floor. i kicked it over and on the second kick she fired up, raced a little and settled. stoked. about 2 minutes later she boggs and dies. wont start back up but for more than a second. i check the plugs and they are soaking wet. change them and can't get her to run for more than a second again. im not sure whats going on. im thinking that the po over jetted the carbs to compensate for the worn needle jets. so now with new needle jets, its soaking the plugs and wont start. so...i took the carbs off and checked everything out. the floats are good, needle good, and carb clean. i changed out the 260 main for a 250. put her back together. still wont start because im wetting plugs. so i change out that 250 for a 220. still doesn't want to start. so now i left the tap on again and am re-charging the battery. hopefully tomorrow it will start up long enough for me to figure out how to keep her running.

oh...the carbs are set up correctly. i had them cleaned, set, and sync'd by an RD guy. i did however check the settings and the air screw was set at 1 1/2 screws out. the slides also lift at the same time. i also made sure that the needle was seating properly. im stumped. the fact that i got it to run for a few minutes has kept my spirit from being totally crushed. come on fellas...lets get her going. thanks in advance to all of you helping me out with this.

cheers

hely

74 Yamaha RD350 cafe
 

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coming from a non-2 smoke guy, when you left the tap on overnight, did you flood the crankcase with fuel?
 

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Discussion Starter #8
i believe so. thats what i was trying to see if i was even getting any fuel to the plugs. i don't think that i am. if i leave it on over night she'll start up until all the fuel is gone from the bowl and wont start again. im thinking that the only way she's getting any fuel is by leaving the damn thing no over night. not sure how to fix this.

hely

74 Yamaha RD350 cafe
 

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I think you answered your own question there . . . . As Matt says, you need fuel. If you are emptying the bowls (they are filling overnite, right? That's what you stated) when you start it up, then your bowls are emptying, gas filters/gas line/ petcocks are clogged.

Do you know waht I mean by the crankcase is full with gas? I am not talking about the carb bowls.

And you stated several times "the plugs are wet" . . . which generally means NO SPARK.
 

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Don't leave the fuel tap on. You'll fill the cases with fuel and can bend a rod when kickstarting.

Main jets will have no affect on starting. You can leave them out and still start the bike just fine. What size are your pilot jets? They should be 20 or 25, I think. Make sure they are completely clean.

Make sure you have no air leaks between the carb boots/reeds/cylinders.

Make sure you didn't fuck up the points install and make the bike fire 180deg off. Check that the plugs fire when the cylinder is at TDC.

There should be a bit of hose connecting the two carbs via the enrichener circuit. Make sure that is connected and doesn't have cracks or leaks.

I bet $1 that it's that last one...
 

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Discussion Starter #11
alright ladies and gents...im a retard. i managed to put the floats in upside down. no f-ing wonder i wasn't getting any fuel. flipped them over and viola! she fired up on the 2nd kick. now however it feels as if the left side is carrying the right. i might have un-sync'd them in this whole process. im going to check tomorrow. also..im running very rich. im going to fiddle with the settings tomorrow to see if she'll pull straight through the powerband. right now it feels like it's hesitating. thanks to all who helped out. i really appreciate it.

cheers

hely

74 Yamaha RD350 cafe
 
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