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Discussion Starter #1
So when I try to start after riding maybe an hr or getting gas,its hard to start back up.sometimes I need to give it full throttle for it to start n someti.es not.the carbs have been set to spec's and a lil adjusted.ive tried everything.i replaced one air cut of value. About to order other side.but I'm at dead end now.ive cleaned carbs not to long ago.ive fixed all vacuum lines.can someone help me before I put money then it's worth to put it in a shop.thanks
 

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Usually have to use the choke on mine after a gas stop.
 

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The owners manual states that when the bike is hot, no choke, throttle open half way. If the engine is flooded, full throttle while trying to start, and if cold open choke with no throttle. If you’re doing all these right then there is a pickup coil mod that is supposed to improve hot starting. It’s an electrical issue not a carb issue and apparently pretty common on these bikes.

The mod and how to do it is fully covered here on the site. You can search on the details. The other thing could be the battery. Make sure it’s a strong battery. AGM type work much better than the wet cell.
 

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The owners manual states that when the bike is hot, no choke, ....
But they cool off really quick.

If I open the throttle instead of the choke after a gas stop, it just backfires.

Now, if I use my card at the pump instead of visiting the cashier and lotto scratchers, it starts right up.
 

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Ha, I normally don’t even get off the bike when I fuel up. But the one thing I’ve noticed that’s consistent is the longer I ride before gassing up the harder it is to restart. But I can’t say I’ve ever used the choke other than the first fire up of the day or when it’s been sitting in the cold for a while.
 

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Ha, I normally don’t even get off the bike when I fuel up. But the one thing I’ve noticed that’s consistent is the longer I ride before gassing up the harder it is to restart. But I can’t say I’ve ever used the choke other than the first fire up of the day or when it’s been sitting in the cold for a while.
Is your bike earshaved and re-jetted? Thinking it might be toward the rich side, not a lot but enough that opening the throttle works.

Every other bike I've had needed some throttle for a hot start, so it took a while to break the habit. People tend to freak out when it backfires at the pumps. Also took a while to believe it needed the choke after the relatively short stop. But it fires first time with the choke and no throttle.

I finally began just using my card at the pump, it's the best way to get the tank full without guessing at the amount or going back in to get change. Also don't have to put it on the centerstand, just straddle the bike upright and filler'up.
 

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My bike is stock, at least as far as the air filters etc. I have no clue if the PO did anything. It wasn’t a private sale I bought it at an HD dealer near me. I’m sure their intention was to just move the bike off their lot. The guy said “we don’t work on jap bikes”. The price was good for my first bike so I took it. I have never had it backfire at the pump as loud as it did when I had a weak battery in it. It sounded like a shot gun!! But to be honest the hot starts aren’t really that big of a deal, at least not as bad as some people have stated. Sometimes it feels like it starts before I even take my finger off the starter.
As far as putting it on the center stand, I’ll shamefully admit that I haven’t been able to do it yet lol. I know it’s a technique thing and I’ve only tried a few times in front of the house and since my pavement isn’t very level it feels like I could easily drop it so I haven’t bothered.
 

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Mines even goes into a vapor lock at times
Do you mean the engine cranks, then stops suddenly, then cranks again?

You can check the vacuum line for the petcock to make sure it's dry after running. If gas flows through the line, it floods the front cylinder.
 

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Hot starts with mine are like turning on an electric motor. Bzzt, vroom. ... as long as I don't touch the throttle. I give the AGM battery a lot of credit for that, and clean carbs.
 

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If it has an evap system, it will NEVER start properly. Get rid of the COMPLETE evap system and PAIR system if your bike has one. Put new plugs in it. Take the gas cap apart and remove EVERTHING inside. The gas tank MUST be vented to the atmosphere.
 

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If it has an evap system, it will NEVER start properly. Get rid of the COMPLETE evap system and PAIR system if your bike has one. Put new plugs in it. Take the gas cap apart and remove EVERTHING inside. The gas tank MUST be vented to the atmosphere.
Not one bike sold could ever start hot? Amazing!
 

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If it has an evap system, it will NEVER start properly. Get rid of the COMPLETE evap system and PAIR system if your bike has one. Put new plugs in it. Take the gas cap apart and remove EVERTHING inside. The gas tank MUST be vented to the atmosphere.
Sounds like a lot of extra work just to save a few seconds on restarts. I’m ok with just opening the throttle a bit.
 

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Evap is only on Calif. models, but I was happy to get rid of the air injection. Combined with the earshave, it cleans up a lot of clutter and allows better airflow over the heads.
 

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Discussion Starter #15
So I've gone threw the bike n checked the vacuum line from under tank n it was bent.i fixed that.seems to do a lil better.but I've tested the pick up coils n they are good.but the starter looks burned on about 2-3 coils.thos is the replacement due to installing a radio n I havent been using it.but for $100 from amazon,I thought it would work.new battery.so I believe that's what I need to replace now.was hoping to go to bike week in Daytona next wken.lol
 

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If it’s a new AGM battery, and you have problems, do the pick coil mod.

I never used the choke either unless the bike was completely cold. The “choke” is really just an enrichment circuit that just squirts extra fuel into the intake.

What always worked for me on a hot start (didn’t do the pick up mod) was to just crack the throttle open AS I hit the starter. This pretty much could be similar to using some choke. I just found it easier.

Do you have iridium plugs? They do help.
 

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The EVAP system will seriously interfere with starting if you ever fill the tank over 3/4 full. Gas gets sucked into the charcoal canister and causes a rich starting system. When I bought my first new VN750, and had starting problems, the dealer told me not to fill the tank over 3/4 full. Total BS. The next day I removed the EVAP system, filled the tank all the way up, and never had any more problems. The PAIR system is another piece of EPA GARBAGE. It will cause backfiring and exhaust overheating, plus it seriously clutters up the bike. When I finished removing the EVAP and PAIR systems, I literally had a 5 gallon bucket full of EPA GARBAGE. I also had a much better running and much cleaner looking bike. And I kept my stock intake system, with the airbox and air filters.

Aside from all that EPA CRAP, you need clean properly gapped spark plugs and a nice strong battery. The VN750 has a weak ignition system, and it needs all the help it can get. I wish it were possible to install hotter coils to get a stronger spark.

If you have a carbureted bike, it is ALWAYS better to get rid of any emissions garbage it may have on it. That's my opinion, but I'm sticking to it.
 
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