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Post by rcq92130 on Oct 14, 2014 17:31:28 GMT -5
OK, makes sense. But aren't I losing a lot of potential power? If I read the graphs correctly, the power drops off pretty significantly going from, say, 7500 down to the low 6k's (looks to be about a 13% drop off).
Have no need to get to a higher speed - this little scoot (200 lbs about) does not have a suspension safe at 65 - not even at 60 if there is anything other than smooth pavement. But I WOULD like to have a bit more reserve power to get to desired speed more quickly, or to hill climb w/o losing as much speed.
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Post by rcq92130 on Oct 14, 2014 13:13:20 GMT -5
Have an RPM question for you guys.
My scoot is running very well - great off-the-line accel, good enough top end ... but it's running way below the max power curve at all times in terms of RPM. Only on very rare occassions can I get up to 7K; normally I'm at 6200 or so at WOT (high 6Ks off the line). So I'd like to shift the place where it's operating to a higher RPM without messing up either the low speed or high speed performance.
Currently at 11gr sliders. If i drop that down I'll probably get higher RPM at take off, but probably NOT at high speed.
If I put stiffer springs in the clutch I'll probably get, again, higher RPMs at low speed but no effect on top end (other than maybe a slight BAD effect on max speed).
Is this a time to put in different gears?
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Post by rcq92130 on Oct 7, 2014 15:35:58 GMT -5
Guess I'm not welcome here any more.
Anyone have a suggestion of another forum site similar to this one? I'm new to scooters and know only this one forum.
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Post by rcq92130 on Oct 6, 2014 19:30:33 GMT -5
Have a bit over 400 miles following the BBK upgrade, so it's time to do some WOT checks and do what is needed to tune this thing.
It's a 150cc GY6 with 60mm piston, A9 cam, stock valve size, Uni intake, big exhaust, 30mm carb with 125 mail. I forget the idle jet --- 38 maybe. Large variator w/ 11g sliders.
Have PLENTY of off the line acceleration ---- no interest at all in more there. Top end seems low, though can probably get into the 60+mph range on flat if given enough room.
But the main thing i would like to ask Ally and others is about RPM.
Form rest, at WOT, the RPM goes up to but never beyond about 6700 or 6800. By the time I'm at 40mph (still WOT) the RPMs are down to about 6100. The only time I get up to 7K is downhill when I'm up to maybe 60 or 65 mph.
That means (I think) I'm always operating below the max power and max torque range.
So, before starting ---- isn't there anything i can do to get this thing to skip into a better RPM range?
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Post by rcq92130 on Sept 25, 2014 19:25:42 GMT -5
This is off topic, but I hope helpful.
If I recall correctly, Walmart has a policy of allowing 'travelers' to park overnight in their parking lots and not hasstle them.
If you can find a way to get your truck towed or somehow moved to the local Walmart, at least you might gain a little peace and security while you address the scooter's problems and sort out your next steps.
A thought anyway.
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Post by rcq92130 on Sept 24, 2014 13:20:08 GMT -5
When you say "rocker arms" are you referring to the engine mounting bolt shown in your photo?
I think the side with the nut is 14mm and the opposite side 13mm.
Attach a wrench to the nut and allow it to rest against the support (not the engine crankcase, which is aluminum and could be cracked). Then take a breaker bar to the head of the bolt (opposite side) and turn counterclockwise until the nut starts to turn. From there you can use a simple 1/2 inch ratchet to complete turning until the nut drops free. Jack under the engine with "just enough" upward force to relieve the weight of the engine, which is only about 30 or 40 pounds at that point, and slide the bolt out (it's 6 or 8 inches long).
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Post by rcq92130 on Sept 23, 2014 21:34:41 GMT -5
I think you know I just had a similar problem that turned out to be electrical (bad coil). But i can't help but inject some (hopefully) comic relief: WHY ARE YOU STOPPING?  AND WHY ARE YOU TARGETING THOSE POOR BUMPS |
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Break in
by: rcq92130 - Sept 22, 2014 0:02:30 GMT -5
Post by rcq92130 on Sept 22, 2014 0:02:30 GMT -5
Yes, but we do not get our scooters / engines from "China" but from specific factories. Some have perhaps installed advanced machining capabilities. Others have not.
For example - the Koreans now have perhaps the most modern factories, simply because they are the newest. Their capabilities are, generally, better than those of any U.S. based factory. This is why Kia Hyundai and others are quite possibly the best manufactured cars on the planet (not the most luxurious - just the best produced). but there are, no doubt, other gasoline engine plants in Korea that do NOT have modern equipment and are NOT making top notch product.
I'm not sure how to tell what the different GY6 factories are like and what level of machinery they are using. Your engine number I guess tells which factory made the engine. but how to you know if that particular engine was made with advanced equipment or antiquated equipment? I don't know how to tell this.
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Post by rcq92130 on Sept 21, 2014 1:50:30 GMT -5
oop ---ies
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Post by rcq92130 on Sept 20, 2014 23:59:45 GMT -5
If I turn it clockwise (screwing it IN) doesn't that lean out the idle speed mixture? I though needle out = richer; needle in = leaner.
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Post by rcq92130 on Sept 20, 2014 18:44:40 GMT -5
Mr. Oop:
A quick question, also following BBK install.
Before the BBK my scooter would start at the flick of the start button - never more than a split second before it fired.
Now it seems very reluctant .. will not start at all if I turn the throttle at all .... and if I leave the throttle alone it eventually catches but after several cranks, at first at a very slow rpm, then doing OK. Once started it idles very well and is running well.
What kind of things should i be looking at?
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Post by rcq92130 on Sept 18, 2014 22:36:04 GMT -5
No, not THAT needle - I was speaking about the FUEL needle VALVE (the valve the floats push on when the bowl gets filled with gas, cutting off the flow of fuel into the bowl). If that is stuck you will have fuel pressure right at the entrance to the carb, yet no gas inside the carb.
The floats have a tab between them right over where the needle valve is. The needle has a wire loop on the top (when the carb is upside down) that must fit OVER the tab in the float. If you had the tap ON TOP of the wire loop it might have pushed down on the needle even though gas was not lifting the floats --- which would explain your problem.
I have a 35 main in right now, but have not finished tuning. However, with the 35 it is running quite decently - no popping, no bogging up to 50+ MPH (have not gone faster during break in).
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Post by rcq92130 on Sept 18, 2014 16:46:39 GMT -5
stuck needle valve?
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Post by rcq92130 on Sept 17, 2014 17:49:47 GMT -5
Thanks, Alley!
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Post by rcq92130 on Sept 17, 2014 16:06:41 GMT -5
PUT DOWN THE HAMMER AND STEP AWAY FROM THE SCOOTER!
OK - do an end-to-end check for fuel flow.
Remove the carb, flip it upside down but leave the fuel lines attached.
Remove the cover of the bowl. Now - either remove the floats (GENTLE - IF YOU BEND THE TAB YOU WILL MESS UP THE FUEL LEVEL IN THE BOWL) or simply GENTLY prop them up a bit so the tab is not pushing down on the needle valve. Again - don't bend anything - just a little propping up should do the trick.
Run the engine --- might take a bit before fuel gets through the pump and into the carb. But it SHOULD come squirting past the needle valve. If so you have fuel all the way to the carb.
if not, remove the floats (gentle) and also the needle valve. You now have an open line all the way back to the tank. Run engine. Fule should come squirting out.
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