Trouble starting

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02GF74

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Not a big problem but if possible I'd like the engine to start up quicker.

Not ridden for maybe 1-2 months but once or twice a week I turn on the ignition to let the fuel pump top up the carbs. (probably 5-10 seconds at most)

Choke fully on, crank over for about 5-10 seconds and doesn't fire.

Repeat until battery juice almost gone, it does fire a few times, choke off seems to improve that but engine doesn't run.

Put battery on charge for say 30 mins, on second turn over, first with choke on, then off (I think) engine fires and runs smoothly with no choke.

Now this isn't a problem but an inconvenience in having to remove the tank top and seat to access the battery.

Also when ridden on consecutive days, it does seem start better without choke, bear in mind it was warmer then.

I didn't touch the fuel enrichment system when I last cleaned out the idle jets but is there anything obvious (and simple, other than ride it every day) that can be done to be improve the starting.

The plugs (OEM NGK) are more or less new, as is the battery.

Is it the turinng on to top up the carb bowls that is draining the battery (I may remove the headlamp bulb) to see if that helps.
 
Not ridden for maybe 1-2 months but once or twice a week I turn on the ignition to let the fuel pump top up the carbs. (probably 5-10 seconds at most)
If your gas has up to 10% ethanol in it like ours does, don't do that. Let it stay dry until you're going to crank it up again. All you're doing is adding multiple coats of varnish to your carbs each time you do that.
 
OK, in which case I'd better get the JIS screwdriver and drain bowls. .... but about the poor starting?
 
Amazon.com: Schumacher WM-12 Cable Connector for Battery Chargers and Maintainers - With Quick-Connect Ring Terminal : Automotive

Something like this, to make it easy to charge the battery would help, or to boost the battery. You want to get both halves of the polarized plugs.

If you're running the bike until it comes up to temperature once a week, I think that's a good way to have the bike stored. If you're not going to run the bike frequently, disconnecting the fuel line at the end of the season, and running the carburetors dry (re-connect the fuel line so you don't forget come spring) should keep any deposits from forming. Yes, using the float bowl drain screws is another way.

A lack of choke/enrichener to start tells me the carburetor is set rich. If you aren't in the Denver CO or Quito Ecuador area you probably have 152.5 mains. Going to 150 or 147.5 mains will probably help.
 
Similar issue when first owned the Vmax.
Although I have a battery tender, it isn't constantly connected. Maybe every couple of weeks of the bike isn't used and usually connected a day before use. This seems to have benefited the battery. A previous battery failed early when I used to keep the tender permanently connected.
As for the starting, have adopted a routine suggested by a buddy some years back.
If cool (this England is often) cold start lever full on. Then ignition on and let pump fill carbs. Before start button give about three quick turns on throttle. Then hit start button.
usually revs rise rapidly, so ease back cold start lever so that tick over is low but steady. Since adopting this method starts have proved reliable.
 
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A lack of choke/enrichener to start tells me the carburettor is set rich. If you aren't in the Denver CO or Quito Ecuador area you probably have 152.5 mains. Going to 150 or 147.5 mains will probably help.

The main is 152.5 - it is Canadian model and the carb jets match what the manual refers to as 'US-49 state and Californian models'.

Where I live and do most of my riding is 173 ft above sea level, so certainly not high altitude but I am sure there are many UK owners that have US bikes with, I assume, the same main jets.

If I recall correctly, the main jet comes into play at much higher revs (I think you posted a chart showing which jets come into play at what rpm), so should not make a difference during start up and idle (1,000 rpm). I may look into fitting next size down jets (1.6% difference) but wouldn't want to risk running leaner due to possible engine damage rather than poor starting.
 
OK, in which case I'd better get the JIS screwdriver and drain bowls. .... but about the poor starting?
You're making way too much out of it. Just park it and leave it. The vents are there for a reason. They do the job they're supposed to do.

There are a lot of things that can cause poor starting. Typically, it's not riding it enough. It can also be caused by flooding it. People crank the choke all the way and start turning the bike over and flood it out. I typically put my choke on about half way and it fires right up every time unless it hasn't run in weeks. Then it might sputter a bit and die, then start and run for a bit and die, then it runs fine.

When you're not riding often, it's GOING to make it tougher to start for a while. It's a carbureted engine. It goes with the territory.

There is only one cure: Ride more often. All the maintenance in the world isn't going to help you when it comes to firing up carbs that haven't run in a few weeks / couple months. Ride it down the road 20 miles and it's fixed.
 
When mine is set up right, float levels, A/F setting, and overnight cold, I need full choke for it to fire right up.
That's h9w mine is tuned, full choke, and I'm in Florida, so a warmer start engine temperature than most of you. After it starts, when the revs are high, I close the choke/enrichener about half, and in < 30 seconds, I can thumb it closed.
 
You said: "... turn on the ignition to let the fuel pump top up the carbs. (probably 5-10 seconds at most)..." This should only take one or two seconds, not 5-10. The fuel pump running has little impact on a battery designed to crank the starter and spin an engine with compression. Are you losing fuel from the system? Does the bike smell strongly of petrol? Have you synchronized the carbs? Have you checked the float levels in the carb bowls?

You should put the bike on a trickle charger due to your limited riding in UK. Wire the female connector to the battery and run it under the seat so you can connect by releasing the seat back just like at a petrol station. No more having to pull the faux tank and seat.

Realize you have a new battery, however, recommend you do the Goldwing Battery mod. Details are here on the forum. Pretty simple to pull the stock battery box and drop in a much bigger battery. That took care of my starting and charging issues. I don't have to deal with putting it on a charger anymore or worrying about slow cranking hot starts miles from my garage. I even carried a portable lithium ion compact jump starter until I put in the larger battery. Now that I have four bikes to choose from, the Gen 1 gets ridden less, but still no need to charge the larger battery for starting after sitting for weeks.
 
All good info. I'll try 1/2 choke next time.
Bowls drained to avoid pilot jets gumming up.

Yes, I know the solution is to get out more.....

Should I need to remove the carbs, I'll try to remember to check float levels.
 
You said: "... turn on the ignition to let the fuel pump top up the carbs. (probably 5-10 seconds at most)..." This should only take one or two seconds, not 5-10. The fuel pump running has little impact on a battery designed to crank the starter and spin an engine with compression. Are you losing fuel from the system? Does the bike smell strongly of petrol? Have you synchronized the carbs? Have you checked the float levels in the carb bowls?
Turing ignition to keep fuel bowls full will drain the battery (headlamp on, fuel pump on, vboost cycles, ignition on) - not a huge amount of power but do it enough times, the battery will go flat.... but I'm sure that isn't an issue.

No fuel loss.
No smell of petrol.
Carbs were synchronised, not a big job to do that again.
Haven't checked float height.
 
Go with the trickle charger route first. Simple and least expensive. I did put a headlight cut off switch when I had battery issues, but still use it.
 
Turing ignition to keep fuel bowls full
Again, never do that. If you're not going to ride it, don't turn it on. Period.

The reason the carbs have vent tubes and dry out is largely by design. That way if you're not running it the gas evaporates and is not able to sit there and spoil, gel up and gum up your carburetors. All you're doing is keeping gas in there giving it as much opportunity as possible to spoil and gum your carbs up royal.

Gas in the tank is better protected because there's far more of it than in your carb bowls. What's more even if it does spoil in the tank the fuel filter can help mitigate it.

Once that gas is in your carbs, all bets are off.

So if you're not going to ride it, don't turn it on. Let the gas evaporate and stay evaporated. The thin residue it leaves behind will dissolve after riding 20 miles or so.
 
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The other alternative is to run the carbs dry and then leave them.

Rather than disconnecting the fuel line, I've purchased a switch to turn off the fuel pump that will also act as a theft deterrent. It will mean cutting the loom (bah!!), unless I can find the connector or use spade connectors and it will be mounted in one of the holes of the "knee protectors", just need to make sure it cannot be turned off by accident, even though it is recessed.

This:
1639655129449.png
Goes into one of these holes (obviously photos are not to scale!!)
1639655036606.png
 
my bike came with a switch to cut the fuel pump, it was a toggle type switch fitted just behind the side panel but reachable, I disconnected it as I don't like dry carbs since having to replace every rubber part in the fuel system of my GPZ750 a few years ago when the bike was apart for personalisation reasons, they all dried out and shrank or cracked and fuel leaked all over the place, maybe it is just older bikes with old parts or the atmosphere of a vehicles residence or type of fuel or ahem.....luck
 

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