Manky's XS650 Yamaha

[Olds]

By all means use the meter Andy. Yep Sid is right. Just turn it on (yellow button) and measure the volts at the battery. Doesn't even matter if you get the leads the wrong way round, as it'll just show the volts as a negative value.

[Archie]

but the important question is, hows your new kicker pedal?

[kapri]

The bikes needs to warm up before worrying about spitting back .That's a very good drop at tickover .

[the coppersmith]

agree with Kapri, warm it up first. Decibel reading is OK but not conclusive until it is sat at half throttle.

[Dslam]

Sounds lean to me. Does it spit back when you begin to lift the throttle on (both cylinders) or at tickover. It maybe the throttle cutaway is no longer optimum. You could try raising the needles one notch to see.
I expected it to richen up as apposed to lean out with the baffles in. Maybe the longer baffles help the airflow. Have a look at the plugs and see what colour they are. Milky coffee is where you should be. Too much milk too lean. Not enough milk too rich.

[Manky Monkey]

See, this is why I don't play with carbs!
Because the baffles have a collar at each end, which fit snugly inside the pipe diameter, I was concerned the gases on the outside of the perforated tube, between it & the pipe, would get "trapped" at the back end & cause back pressure. I need that rear collar though cos that's where they're bolted in.
The carbs spit when I blip the throttle.
It's an odd starting procedure. No chokes fitted, so just "tickle" the carbs to fill the floatbowls then kick. If you touch the throttle at all for the first minute or so it'll die. The natural inclination if it starts to falter is to open the throttle, but you can't. So just kick it over & leave it alone. If it stalls, kick it again. Once it's warm, it'll start first kick every time. So yes, the motor was warm.

So next time, give it 5 minutes to properly warm up & if it still spits back, try lifting the needles a notch Andy?

The new kickstart pedal's at the powder coaters Archie. Should have it back at the end of the week. 

[Dslam]

Yes mate, Lift the needles a notch. This may screw up the carburation up the range but can indicate if the throttle cutaway is the issue which I suspect. When you reassemble make sure the slides are still lifting equally.

[Manky Monkey]

Alright, in my garage & I've just fired it up again, (minus the baffles for now). The Meter's reading 12.7 when the engine's running, (sidelight & tail light are wired into the ignition switch so they're on all the time). Revving it doesn't change the reading. Switched it off & now the Meter's showing 13.

[Manky Monkey]

2 minutes later & the battery reading's risen to 13.2

[Manky Monkey]

https://www.youtube.com/watch?v=LE0HGTvKJhc&t=6s

The marvels of modern technology! Wobbly video of the bike a few minutes ago.
Needles raised one notch, (now on bottom notch).
Plugs are sooty. Dry, but sooty black.
Didn't have a wire brush to clean them so wiped them with a cloth & put them back in.
Baffles are just pushed in loose for now & vibrate out when it's revved! Seems to be picking up cleaner now.
For some reason there now seems to be more top end noise than before. Sounds cam chainy. Not horrendous, but I ought to check it's adjustment while I remember.

[Manky Monkey]

Cam chain adjustment correct. Also noticed the indicator switch was on, although there's no flashers fitted at the moment, (they're at the powder coaters). Don't know if that would show as a draw on the battery, along with the lights?

[Dslam]

A bit difficult to ascertain whats what on the vid. The top end noise may be down to the uneven tickover. I suggest you get the baffles bolted in and get it MOT'd and we will have another look at the carbs to compensate for the baffles.
The charging is a misnomer coz it aint!
The discharge is down to the bike being run and the battery is recovering after it is switched off. It is possible that the battery is fully charged and the regulator is dumping the charge but I am no expert where alternators are concerned. I'm more of a dynamo/Magneto kind of guy.

[Manky Monkey]

Baffles are bolted in now.
I don't understand electrics at all. Never have, although I've managed to replace or splice in various bits of loom over the years. So still charging problems then. I've no idea how you check the regulator/rectifier.
Sooty plugs?

[Manky Monkey]

.

[kapri]

I'd find a way of rigging a spring to that baffle so that it comes out as you rev and automatically goes back in . No other reason than I'd find it amusing.