u/DiabloRed520

2019 keeway rks 125 EFI

Symptoms: Bike will start but only with throttle assist. Bike will not idle.

That’s it in a nutshell. What brought it to this point was trying to diagnose and fix extremely jerky riding at low speeds where a mere fraction of release on the throttle would result in sudden speed reduction. Basically impossible to control, eg. 25 down to 20 smoothly. So airflow mix at idle was suspected.

What’s been investigated and or replaced. In rough order.
IAC valve. Replaced
Fuel injector replaced (OEM).
Fuel Pump replaced (OEM)
Throttle body removed and thoroughly cleaned.
No air leaks detected (spraying brake cleaner)
IAC valve. again. I’ve tried at least three. One from Poland (OEM) and current one from China.
Coil was replaced. (OEM) Though the original only suspected.
MAP sensor replaced and voltages in spec.
Spark plug changed. (Twice)
Battery New.
TPS was last straw even though previous one didn’t indicate electrical issues. So a new one (China)

The ECU is a year old. And shows no suggestion of fault. It was replaced because the bike would rev wildly and erratically and stall arbitrarily. Behaviour after that was much better and bike was rideable but then the jerky throttle situation arose.

Throttle cable cleaned and adjusted. No tight spots and smooth return.
Fuel pressure is good
Spark is strong
All IAC valves can be heard resetting at shutdown so there was definitely pintle movement.
Air filter clean.
Throttle stop screw adjusted. When I put the throttle body back the butterfly was basically shut. It currently sits about 3x 1/8th turns open. I had opened to 6x 1/8ths with perceived minor changes to throttle action (stalled later) but I don’t think simply opening more is the solution.
TPS reads 0.52v at its minimum adjustment. Currently it’s 0.6 due to throttle stop screw adjustment.
Idle spec is 0.5 - 0.9v

So. Starting requires throttle. Maintaining running requires constant catching manually. Releasing throttle stalls.
I’m at a loss as to what can be done next. I am wondering if an OBD device would give me any useful information. So suggestions there as to type and iOS software would be useful. Keep costs low.
The obd port is a 16pin trapezoidal connection so I’m thinking an adapter cable is not necessary.
Euro 4 2019.

I’m buying a boat and have got through the survey part. My question is one for opinions from experienced boaters on power.

The listing stated 3 leisure batteries. I personally saw 2x260ah (two sixty)but really it didn’t occur to me to shine a light further under the deck to see what else was there.

The survey indicated 3 leisure at 250ah ea. (two fifty) but noted access was difficult. “Only two were able to be seen, the others behind fixed panels”

As part of the negotiations and since the batteries need replacing the quote from the marina stated there were only 2 x 260ah leisure batteries.

The boat has no solar. I would prefer to not have solar added (expense/looks). All the while I was Mentally getting comfortable with a bank of 780ah (of course that’s not actual available) but now I’ve essentially been cut by a third down to 520ah to start with.

I have no experience in actual usage and am trying to determine if I should be overly concerned with the now reduced battery capacity.

I do not plan on having a tv - if I do it’ll be 12v. The fridge and separate freezer box are 12v. Heating is via Eberspacher Diesel.

Side note. Should I decide or need to add a third battery of same size and brand - I would do it within a few months of purchase - is this a simple case of connecting with cables to the current two? IE a diy. Assuming space of course.

There is a 3Kw inverter multi plus on board. I plan on being a continuous cruiser so take into account week long stays.

Thanks in advance.