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01 Sep 2014:
I performed the 8400 mile service, which is inspecting the brake system. Nothing much to report here. I plan on ordering new brake fluid reservoir covers, or finding some paint that can stand up to brake fluid... now the paint's starting to peel a bit on the right-hand brake fluid reservoir cover, too.
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05 Sep 2014:
I received the valve rocker arms, rocker arm shafts and O2 sensor I ordered from KymcoPartsMonster.com. I'll ship the rocker arms and rocker arm shafts to Baisley Hi-Performance first chance I get.
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07 Sep 2014:
My 56th fuel up, I filled up with 87 AKI octane fuel from Costco.
Mileage: 8512.5 miles
Miles Ridden: 190.6 miles
Fuel: 2.555 gallons
Price/Gal: $3.579
Total Cost: $9.14
Fuel Mileage: 74.60 MPG
Yet again I hit a new all-time high on fuel mileage. No idea why, it's been relatively cool here recently, and usually my fuel mileage goes down when the temperature is low.
I added an ounce of Startron Enzyme Fuel Treatment to the gas tank.
I performed the 8500 mile service as soon as I got home, which is inspecting the steering head bearing. It involves twisting, prying and lifting on the front end and handlebars to see if it sticks, wobbles or can move where it's not supposed to. Nothing to report here, although when I have the Tupperware off for retrofitting the experimental devices to the engine, I'll take the steering head bearing out, do a visual inspection, and grease it.
I replaced the O2 sensor and took the bike out for a 30 mile test ride. Other than it having a bit more power, nothing changed... now I have to be extremely careful not to hit the rev limiter... I pegged the tachometer three times on the test ride. It resets after 30 seconds or so of less-than-rev-limiter riding, but it's disconcerting when it happens to see the tach pegged at 10,000 RPM. But pulling up those long hills on Interstate 280 near Half Moon Bay at 70 MPH was fun... the engine's got more in it if I can figure out a way to gear it a bit taller and get it nearer its torque peak.
So the old O2 sensor is still working, the heater still works, etc., so I cleaned it up and stored it in my spare parts box.
The rough idle persisted, so the O2 sensor wasn't the culprit. In doing research, I found it may be the Idle Air Bypass Valve that is sticky, so I cleaned it with some throttle cleaner I bought at Kragen that's supposed to be safe to use in cleaning throttle plates, O2 sensors, fuel injectors and air bypass valves. And I plugged in my Kymco Diagnostic Tool to be sure everything was kosher. Aside from a Diagnostic Trouble Code of 13 (engine overspeed), there were no errors.
I noticed that the engine Idle Speed Setpoint was at 1716 RPM instead of 1660 (factory setpoint), so I reset the APC (Air Per Cycle) valve in the Kymco Diagnostic Tool settings, and that dropped the idle speed back to its factory setpoint. I've got to let the engine cool before I know if the changes fixed the cold rough idle. If not, I'll be changing out the spark coil, spark plug, spark plug wire, and the fuel injector next. I think I'll go with a higher-power spark coil. If none of that works, I'll order a new idle air bypass valve. It can't be a vacuum leak, as it only happens when the engine is cold... when it's warmed up, it idles smooth as silk.
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08 Sep 2014:
In chasing down this lumpy cold idle gremlin, I was watching YouTube about motorcycles with lumpy cold idle. One of the guys said it was due to his valves being misadjusted. So I checked the valve clearance, the secondary air injection control valve, the spark plug and the timing chain today.
Nothing out of the ordinary to report.
I cleaned the spark plug, using an emory board to shine up the J-hook, just in case the spark was having trouble jumping the gap due to carbon buildup on its landing zone. Then I made sure it was gapped to 0.9 mm. I put a dab of copper antiseize on the threads, and torqued it to 10 ft-lb. I know the manual says 6.5 ft-lb, but that seems awfully loose... it barely crushes the crush washer at that torque. The good news is I started the spark plug threads 180 degrees from where it'd been put in last time, so the J-hook isn't shrouding the spark from the intake valve anymore, the plug's open gap is pointing almost directly at the intake valve now. No indexing washers needed.
The secondary air injection control valve was a bit carboned, but not bad. I cleaned it up and put it back together.
The valves were at exactly 0.09 mm, just as I'd set them. I know they're supposed to be set to 0.1 mm, but that ever-so-slightly tighter valve clearance gives me just a tad more valve lift, which gives the engine a tiny boost in power, without unduly risking slamming the valves into the piston.
The timing chain and chain tensioner look practically new. No wear, no problems.
I also went through and tightened all the clamps on the intake manifold and the various tubes, just to be sure there wasn't a leak on one of them.
Unfortunately, the problem persists.
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09 Sep 2014:
I tore into the bike pretty deeply today. I took apart the entire intake from the air filter to the engine, cleaned up all the parts, ensured everything was in good condition, and put it back together. I did the same for the fuel system from the fuel hose to the fuel injector.
I found some very, very fine grit covering everything from the fuel hose, the fuel injector, the intake, etc. It was pretty apparent it came in via the fuel, you could see in the throttle body where it'd been sprayed on the walls by the fuel injector. So a bad batch of gas is the culprit. That means I'll have to replace the fuel injector, as it's partially clogged with the stuff and no amount of cleaning will fix that.
And I'll have to find better fuel filters. The ones I'm using are Wix 33031 / Napa 3031 filters, with a metal canister body and paper filter element. They have a 12 micron filter rating. So the fine grit getting through the fuel filter was finer than 12 micron. But it clumped up everywhere.
I pulled the old fuel filter out and put a new one in. It's getting near to the time when it needs to be changed anyway. It was put in at 6000 miles, and is due for a change at 9000 miles. It'll get swapped for a more efficient filter as soon as I find one. The old fuel filter, when looking down the tube, had the grit built up on its filter media, so Costco must have given me quite a large dose of the gunk.
I stripped every part down as far as it'd go... the fuel injector actually comes completely apart. But I nicked the O-ring when I was taking it apart (it was really stuck together), and that tiny, tiny nick caused it to leak fuel when I'd gotten it all back together. So I went to Kragen and got a Viton O-ring of the same size and put it in. Leak fixed, problem solved.
I found the Throttle Position Sensor can actually be pivoted back and forth to adjust the sensed throttle position. I got the bright idea that if I slid it all the way toward the forward position, the ECU would think the butterfly valve wasn't fully open, even though it would be, and hence it'd feed the engine less fuel, improving fuel economy.
It works, but there's a side effect. At a certain RPM, the engine just cuts out. The closer you are to adjusting the TPS so it reads 100% when the throttle is 100% open, the lower that RPM will be right off of idle. I started with the TPS all the way forward. The Kymco Diagnostic Tool showed the throttle position sensor as reporting the throttle only open 91%.
"A 9% fuel savings!", I think to myself, "Great!". I buttoned it up and took it for a test ride, whereupon I discovered the flaw in my brilliant plan. The engine was cutting out at around 4500 RPM, which is right where the RPMs are when I'm taking off from a stop with light throttle.
Apparently the ECU switches between "open throttle" and "closed throttle" modes, and there can be no gap in throttle position between the two, or the ECU just shuts off the fuel injector in that gap.
So, I went back home, and adjusted the TPS so it was showing 96% open when the throttle was actually 100% open. Another test ride revealed the engine would cut out if I just barely cracked the throttle. I kind of like it like that... it allows me to coast in traffic without using fuel, and the engine cuts out at 3000 RPM, an RPM that isn't even usable given that the clutch doesn't start engaging until 4500 RPM. Cracking it just a slight bit more makes the engine jump to 4500 RPM.
But, knowing that it ought to be seamless between idle and open throttle, I carefully adjusted the TPS position until it was exactly correlated with the actual throttle position, then I did the TPS reset procedure. Just can't win. Heh.
See attached pictures.
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10 Sep 2014:
I went out to the garage last night to go to work, started the bike, and it only did the lumpy idle thing for about 10 seconds before it smoothed out. I thought, "Great, it's improved, but I'll still need to change out the fuel injector."
This morning, when the engine was at 56 degrees because it'd been sitting in the parking garage at work all night, when I fired it up, it only gave two slight "rum-dum-rum-dum" lumpy idle things, then smoothed right out. No rich exhaust smell, either.
EFI is a strange beast. Apparently it's relearning the sensors and setting things up so it runs well.
So I may not have to replace the fuel injector after all... time will tell.
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13 Sep 2014:
I performed the 8600 mile service on the bike today, which consisted of:
Replace engine oil and filter
Clean engine oil filter screen
Replace gear oil
Engine oil - Royal Purple 15W-40 Fully Synthetic Motor Oil
Gear Oil - Royal Purple MaxGear With Synerlec 75W-140
Oil Filter - HighFlo HF562
There were no metal flakes of any size in the oil. Nor was there any in the gear oil.
I added a small amount of STP Oil treatment with ZDDP to the engine oil.
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16 Sep 2014:
I ordered 2 new air filters (Part Number: 1721A-KKC3-900) from KymcoPartsMonster.com.
Each: $17.10
Subtotal: $34.20
Tax: $0.00
Shipping: $20.62
Order Total: $54.82
Order number: 33957
According to my tally, I *should* have 4 OEM air filters on the parts shelf... but my wife, being ever-so-efficient, decided to move everything in the garage around, and now the filters have gone missing. Heh.
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17 Sep 2014:
I want to try something new for air filtering, so I went to Jo-Ann Fabric and Craft Store and purchased a 2 inch thick, 2 foot by 2 foot square of synthetic woven pillow stuffing made of polyester, called NuFoam... it's almost like an open-cell foam. The stuff is sort of melted together so it can't come apart, and it'll make a great oiled pre-filter when it's compressed to 1 inch thick. I'll build a semi-circular holder from perforated metal for it that'll bolt in front of the existing filter. For the oil, I'm thinking of using Motor Honey oil or other similar thick oil substance... it's very thick and tacky, and thus should catch and hold dust.
For the built-in filter, while I've got the two OEM filters on the way, I also want to try out an oiled filter... the gear oil vent is putting oil vapor into the air cleaner housing anyway, which eventually leads to the air filter having oil on it anyway, so why not just have an oiled filter that'll catch more dirt and allow easier breathing? At least then the oil vapor coming from the gear oil vent will keep the air filter oiled and working well, whereas now it just tends to plug the paper filter element. And an oiled filter is cleanable and reusable, so it'll save money in the long term.
Here's what I purchased:
http://www.e-dnafilters.com/Product.asp?ID=1550DNA Filter P-KY1SC09-01
You'll note it says it's for the Dink 125i, but the Dink 125i and the Yager GT 200i share the same air filter part number.
I also ordered the DNA Filter Service Kit (the filter cleaning solution and filter oil).
Total: $112.90
Order Number: 2285.224254648
Tracking Number: RE334476171GR
So that's approximately equivalent to the cost of 6 OEM filters.
An alternative oiled air filter is the BMC FM700/04.
http://www.bmcairfilters.com/filtri-moto-standard/fm700-04_d1133_10.aspx$59.00 from speedmob.com
It's been confirmed by BMC that it fits the Yager GT 200i, as well.
I may order this one, as well, to compare the two.
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20 Sep 2014:
Curiosity got the better of me today, so while I had the Met-In Box off for measuring free space for a new 5 micron fuel filter (my current fuel filter is 12 micron), I popped the little rubber plug out to access the adjusting screw on the intake plenum, as discussed here:
http://www.kymcoforum.com/index.php?topic=12666.0I turned it all the way in, just so I knew how far to turn it back out when I was done playing. It was exactly two turns out.
Turning it all the way in gives that rough, stumbling idle *all* *the* *time*... so that gave me a clue that this might be the last little bit that needed cleaning to completely smooth out the idle. I'd already cleaned the fuel line, fuel injector, intake plenum and put a new 12 micron fuel filter on previously.
So, I screwed the screw all the way out while the bike was idling, and removed the screw. It's a needle screw, obviously for adjusting the idle fuel:air mixture... even though we've got an Idle Air Bypass Valve, I guess this is the fine adjustment.
I sprayed some throttle cleaner into the hole, cleaned the needle, then popped the upstream hose off the Idle Air Bypass Valve and sprayed a bit of throttle cleaner through it as the bike idled. It died a couple times, but started right back up.
Taking the engine's response from when I'd turned the needle screw in all the way, I gauged where the rough idle started, then backed it out until it was idling smoothly. It's now only 1 turn out, instead of 2, and the idle is smooth as butter.
I'll adjust as necessary in the future if I find it's necessary.
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21 Sep 2014:
My 57th fuel up, I filled up with 87 AKI octane fuel from Costco.
Mileage: 8689.8 miles
Miles Ridden: 177.3 miles
Fuel: 2.548 gallons
Price/Gal: $3.499
Total Cost: $8.92
Fuel Mileage: 69.584 MPG
Not bad, considering that I had the fuel leak from the nicked fuel injector o-ring, and I also lost a bit when I changed out the fuel filter.
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22 Sep 2014:
I finally got around to mailing the OEM rocker arms and rocker arm shafts to Baisley Hi-Performance today. I'd put them up on my parts shelf, and every time I went to the garage, I reminded myself to mail them, but never got around to it.
Well, I was tweaking that little adjustment screw on the intake and spraying some more throttle cleaner through there and through the Idle Bypass Valve, when I spied the package on the shelf, and thought, "Yeah, I'd better get that mailed out before they forget who I am." Heh.
For the record, that little adjustment screw under the rubber cap on the intake plenum is now three turns out. The cold idle is almost completely "lump" free. I suspect there's still a bit of gunk somewhere that needs to be cleaned out. I'll get the opportunity to tear it all apart and do a deep cleaning when I install the experimental components on the engine.
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