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High RPM:

My first instinct is to check that the throttle cable is adjusted properly to ensure the throttle blade is being allowed to completely close. Given that the design of the carburetor places the throttle blade behind the main fuel metering apparatus, an air leak in the manifold shouldn't be able to cause a high RPM situation (I'm not sure I'd call 4K rpm an 'idle') especially with the A/F screw bottomed out (which IIRC should completely cut off all fuel through the idle circuit).

Check also the automatic enricher servo. If it's stuck in the 'on' position, and you have a vacuum leak in the manifold, it's plausible that such conditions could result in the high 'idle'.

It's also 'possible' the vacuum actuated petcock is faulty allowing some fuel to enter the manifold via the vacuum hose. However this too would pretty much require an accompanying vacuum leak in the manifold to supply a viable air/fuel mixture to cause the high RPM condition, otherwise the fuel would most likely flood out the engine causing a stall.

From here all I can do is randomly speculate. It's possible the float itself is either malfunctioning or the needle/seat is failing to seal properly. In either case the fuel level could plausibly exceed the limits of the bowl, allowing some to seep into the throat of the carb, and thence be drawn into the intake manifold. If there is indeed an air leak in the manifold it's plausible that a 'perfect storm' of variables such as the above would account for a high 'idle' under the parameters you describe. Note however this is pure speculation.

Fuel gauge:

My first step would be to check the fuse panel. If the fuse is 'OK', then next I'd apply a multimeter or 'test light' to the wires at the gauge end of the harness to check for voltage, and work my way back from there (Note: I have, in the past, seen a fuse look perfectly fine, yet be faulty...testing a replacement fuse would not be a wasted effort 'just in case'). If you don't have a multimeter, then you could try checking the gauge for function by using some jumper wires directly from the battery to the gauge terminals. If the gauge 'functions' (read: moves) then you may safely presume that the gauge itself is fine, but it's not receiving voltage 'signal' for some reason (I'm presuming the fuse 'checked out').

The next physical thing to check would be the float/sending unit assembly in the fuel tank. Ensure proper mobility (read: make sure it's not seized in one position).

If the float arm moves freely then at this point you MUST dig out a multimeter to do any further diagnostics. You will need to set for OHMS and check for variations in the readings at the terminals of the sending unit on top of the tank (where the wires plug in) as the float arm moves up and down. The actual numbers don't matter at first...you are checking to see if there is an electrical short/failure in the sending unit. If there is zero change in the numbers as you move the float arm up and down, then the sending unit is 'bad'.

If the sending unit and gauge check out as 'functioning', the fuse is 'OK', and you have made sure all connections are clean and tight, then the only thing left to do is a point-by-point continuity test on the wiring harness from the tank to the gauge. You have my sympathies. (I HATE tracing electrical faults!)

Mystery switch:

Looks like a three position headlight/kill switch. Probably disconnected/bypassed by the previous owner. (which leads me to believe the fuel gauge issue may be related by similar circumstances)

I don't have a dog in this hunt, but I do feel the need to point out that not all grades of stainless steel are 'magnetic'. In fact, most aren't.

While admittedly the 'sharp edge' of a curb or pothole is not the same as 'rough' off road terrain, have you SEEN some of the jumps (and landings) those competitive mountain-bikers do? (and yes, I understand that most modern MB's do have suspensions now...but that wasn't always the case, and they are typically carrying twice the load I intend too)

The thought of a suspension has crossed my mind though. It would add complexity, cost, and weight, and I think I can figure something out but it may just be simpler, lighter, and less expensive to carry a spare wheel.

The trailer idea I have formulating in my mind would be constructed of 3/4"(id) steel electrical conduit, and utilize mountain bike wheels. Something akin to this, only without the angle iron. I still don't understand why, if they had a tubing bender, they didn't take the time to do the maths and make the perimeter of the frame a single piece of tube. As a welder/fabricator by trade I can tell you it's not *that* hard... and I SUCK at math!

I imagine the whole thing would weigh maybe 15lbs 'empty'. Those 6.5 gal tanks weigh in around 5 lbs (I went out in the garage and hefted an empty one...I have three), so..20 lbs tops combined. 6 gallons of gas at 6.25lbs/gal nets 37.5 lbs...call it 40 lbs for fudge sake, and the total is now 60lbs for trailer, tank, and fuel. Add another 10 lbs for the decking/sleeping platform, tarp, and bedding. 70 lbs. is getting 'up there', but that's everything I imagined hauling on it, and depending on how much room I have on the pillion seat, I may relocate some of the bedding up there for a 'backrest'.

In my mind's eye I'm envisioning a 'deck' 24'' long x 24" wide, with three layers of decking hinged in 'accordion' style to fold out to a flat sleeping surface 60"l x 24"w (I'm roughly 5'7" so an even 6 feet of deck is plenty). Holes will be drilled in the deck in six locations to accommodate 'pockets' in which light-weight 1/2" PVC slip-together 'square' arches will be fit. Throw a tarp over the top and you have a dry sleeping place for the night. The fuel tank would be fit under, and suspended from, the deck rails to lower the CG.

The braking thing *might* be an issue, but given that the scoot is designed to accommodate two-up riding (with an advertised 'max load' of 385lbs), and myself clocking in at under 200lbs, it seems that total braking load is well withing engineered specifications.. However it did make me think, so prior to finding out the max load I went out to the garage to look the scoot over a bit, and found that the rear brake is cable operated. Working the hand lever I watched just how much 'throw' the drum lever had, and determined that I could rig a bicycle brake cable to the drum lever and give the trailer it's own brakes. I could even make them adjustable for varying loads!

The primary reason for going with a 6gal. marine tank is partly the fact that all the fuel pick-up engineering has been done (as opposed to figuring out how to do it on a smaller Jerry can), and partly the 6 gal capacity completely eliminating the need for any mid-day fuel stops. I'll either top up as I wind up my riding day, or first thing the next morning...and short of any mechanical breakdowns or biological needs, I'll be set for a day of non-stop seat time. I'm hoping I can offset any 'time lost' to slower speeds through towns by holding a 'cruise' speed between 45-50 in order to average out/achieve the overall 40mph average goal.

I hadn't thought about the oil change intervals. Didn't realize they were so short! The oil I intended to pack along was just one quart of 'emergency' oil...any oil changes en route would in fact be done with locally sourced oil . I guess I'll have to add a small funnel to the list of tools. BTW...last engine/trans oil change I did, I glued some small neodymium magnets to the tops of the plugs. presuming this succeeds in trapping metallic particles, would that increase the oil change intervals, or is the interval set more by the blow-by from the piston? Also...why the extra filter plug? It doesn't seem like it would be a wear item.



I'd like to avoid a trailer if possible, though having a small one DOES increase capacity. I could even make it just big enough for the extra tank and switch to an actual fuel PUMP (such as those used on the floor-tank-equipped Ruckus). that would greatly lower the center of gravity vs. having a full tank up on the package rack. Money *IS* a factor in all this so springing for a couple of top end rebuild kits is probably not in the offing. The same goes for a complete spare carb and (sadly) most likely the AAA membership. 12vdc outlet is a good idea. One that I had already thought of, but forgot to list. As for tools, I plan to have a small 'pocket' socket set, a selection of box end wrenches, a 'multiple 16th's wrench', and a specific pair of screwdrivers I have that allow me to make idle speed and mixture adjustments without removing ANY body parts.



Oh I have zero delusions about it being anywhere *near* fun, but money constraints force time constraints. However, I fully intend to limit myself to no more than 10 hours of actual seat time each day (or 400 miles...whichever comes first ) and then get off and stay off the bike for the remainder of the day, even if I feel like I'm wasting perfectly good ride time.



If I could afford to get another platform, I'd just step up to an actual motorcycle. Lately I've been giving the Yamaha V-Star 650 a good, HARD looking at. I've seen several in the $2500-3500 range around here. Unfortunately, the fact that I am stuck with what I have (the Roketa 150) is the whole reason this thread was even worth creating. Going cross country on a 650cc cruiser isn't anything special (in the MC world that is)...doing it on a 'cheap' Chinese gy6 clone on the other hand...

Pick yer poison.

I think you'd have far better luck with one of those E-bay 'electric superchargers'.

Who knows... with such a small engine, it MIGHT actually create a tiny amount of boost!