its alive (almost)

roadstar06

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so after a year and half of building my bike I finally tried to start it up for the first time. it cranks up but only got it to run for 15 sec. then dies, any suggestions on what to try? I've already tried to advance timing a bit and messed w/ carbs ever so slightly which seemed to help...
 
We'll need a bit more info. Points ignition still? Old original points or new replacements?
 
no I'm runnuin HHB cdi system.Mikuni vm 34s,short headers...I also noticed that the inline gas filters have air bubbles in them??? could this be my problem??new gas tank w/ 2 outlets- inline filter are cone type-see thru plastic. bike wants to start on every 3,4th kick but something is preventing it from firing up. i have gotten it to start and run ever so briefly (20 sec.) best so far, has started and died about 10x now. sad part is with all that kicking yesterday I threw my back out and can't work on it today.
 
i don't know if floats are set- took them out of the box and bolted them on .according to tc bros there set to go from them
 
Don't believe what after market sellers tell you. They all tell you they are ready to use. Its called marketing ; aka hyperbole, fibs etc. 650central has a good reputation for correctly jetting carbs to suit your engine. Any carb that is unknown to you, must be taken apart and checked for float level and correct jets, depending on air filter and exhaust selection you have. You better take some time and read VM carb guide that is in the TECH section.
 
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So outta curiosity did your CDI system from Hugh come with the sheet showing you to reverse the red/green pickups at the plug &I did you trace/confirm if this was correct on the system you installed? "If" this wasn't done your timing will be way advanced. She'll start - die - start - die....don't ask how I know....
 
So outta curiosity did your CDI system from Hugh come with the sheet showing you to reverse the red/green pickups at the plug &I did you trace/confirm if this was correct on the system you installed? "If" this wasn't done your timing will be way advanced. She'll start - die - start - die....don't ask how I know....
umm, no info on switching wires around- I hope your kidding me
 
Not joke man - it's 1 sheet not attached to the novel he ships for install. This is the best I got for a pic, sorry. Can't find mine...yet again.

IMG_5022.JPG

The pickup is from an opposite rotation motor, hence the need to flip the wires or it'll read reversed. Hugh says sometimes they flip'em prior to shipping ...sometimes not - he states on there to trace the wires from pickup to plug and see if it flips from green to red at any point - if not ...reverse it. I'd give a quick crack at just backing out the pins from the plug and reverse for tricks. If it magically runs...blame the wife/gf - it's my excuse for the sheet continually disappearing
 
Not joke man - it's 1 sheet not attached to the novel he ships for install. This is the best I got for a pic, sorry. Can't find mine...yet again.

View attachment 104527

The pickup is from an opposite rotation motor, hence the need to flip the wires or it'll read reversed. Hugh says sometimes they flip'em prior to shipping ...sometimes not - he states on there to trace the wires from pickup to plug and see if it flips from green to red at any point - if not ...reverse it. I'd give a quick crack at just backing out the pins from the plug and reverse for tricks. If it magically runs...blame the wife/gf - it's my excuse for the sheet continually disappearing
unbelievable! hey thanks for the info, as soon as my back feels up to it i will check it out.
 
Not joke man - it's 1 sheet not attached to the novel he ships for install. This is the best I got for a pic, sorry. Can't find mine...yet again.

View attachment 104527

The pickup is from an opposite rotation motor, hence the need to flip the wires or it'll read reversed. Hugh says sometimes they flip'em prior to shipping ...sometimes not - he states on there to trace the wires from pickup to plug and see if it flips from green to red at any point - if not ...reverse it. I'd give a quick crack at just backing out the pins from the plug and reverse for tricks. If it magically runs...blame the wife/gf - it's my excuse for the sheet continually disappearing
checked this today and they are already flipped - how much of an open gap should there be on the vm34 slide? should it close completely or stay open a bit?
 
The VM slides should be open a little bit. That's how the idle speed is set and controlled, by raising/lowering the slide a little. If you watch the slide while adjusting the idle speed screw on the side of the carb, you will see it lift as you screw it in, drop as you screw it out. You need to match the amount of opening carb to carb for the carbs to be "in sync" and for both cylinders to be idling at the same speed. Then you have to match the freeplay in each throttle cable so the slides begin to lift at the same time when you open the throttle. That will get the motor "in sync" at higher speeds.

Syncing dual cable carbs like these is a 2 step operation. First you set and sync idle speed, then sync for "at speed" (throttle opened) operation.
 
The VM slides should be open a little bit. That's how the idle speed is set and controlled, by raising/lowering the slide a little. If you watch the slide while adjusting the idle speed screw on the side of the carb, you will see it lift as you screw it in, drop as you screw it out. You need to match the amount of opening carb to carb for the carbs to be "in sync" and for both cylinders to be idling at the same speed. Then you have to match the freeplay in each throttle cable so the slides begin to lift at the same time when you open the throttle. That will get the motor "in sync" at higher speeds.

Syncing dual cable carbs like these is a 2 step operation. First you set and sync idle speed, then sync for "at speed" (throttle opened) operation.
ok, so I had a throttle cable made by Motion Pro , installed it and the slides are open i'd say little less than 1/4"- i'm thinking and have also seen vids of people with slides at 5/32" or less but I can't adjust them down anymore - thinking cable should be a touch longer- adjusting air screw will bring it down more??
 
screw method not working- how much free wire should there be going into carb? told guy at motion pro to make it 3" i think- if I delete the 45 on carb will i gain any length? I should I think.
 
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