Potential GY6 Engine Issues

[tortoise]

Before posting a query, make a worthwhile effort to review previous forum contributions . . utilize Google Custom Search at bottom of page. If needed, replace "print" with "display" in the URL for best viewing.

Ask-Hole Syndrome
"Someone who consistently abuses internet fora and discussion boards to post stupid questions a quick google search could have easily answered. Usually withholds relevant information so that even posters trying to help cannot really solve his problem adequately. Utterly disgraceful and quick to insult anyone who refers him to google or other sources."

Is the injury risk acceptable?
Classic left turn scenario. Another variation.
3/4 helmet downside. UPS van faceplant.
Enhance your survival odds with a full-face helmet.[/b]

Parts Vendors . . Scooter Belt (125/150cc belt change video) . . Scrappy Dog . . Parts For Scooters . . Rolling Wrench . . Scooter Works . . Enviromoto . . connectors

Scooter selection research most common regret . . expectations . . guidelines . . brands.
State of the scooter scene 2013 part one
Honda - Yamaha - Kymco - Sym - Genuine - Eton - Peirspeed - Lance - Qlink
Heeters offers online sales of the "higher tier" Tomos scooters made by Sym China.
Most GY6 engines only have an oil strainer screen. The Genuine 125 has an actual engine oil filter element . . potential downside.
Used scooter pre-purchase registration research.
Craigslist searchs: Honda Elite 110 . . Honda NHX110 . . Zuma 125 . . Sym HD200
Zhongneng (ZNEN) factory video. Tao Tao engine assembly line video.
AZ Imports scooter assembly videos.

Potential 50cc issue. TaoTao advisory.
The downside of "ride it like you stole it" engine break-in.
Other than troubleshooting and routine maintenance . . leave it alone . . seized engine.
Performance air filter issues. Performance cooling fans increase engine temperature.
Big bore kit (BBK) potential issues . . pistons and rings . . longevity . . variator.
"Gaming the system" . . consequences . . rare arrest.

139QMB variator 5 gram rollers (replacement slides) will keep the CVT drive in "low range" longer for better performance on hills and into headwinds, but may decrease top speed by a few miles per hour. There is NOT a standard stock variator weight, so to determine they have to be removed from the variator and weighed (post office scale is one option). Rollers versus sliders discussion.

Per GY6 150cc related blog article . . "seems to run better all the time and with almost 7,000 miles on it I have to be careful with the throttle to keep it at 45 mph to preserve the motor. Low engine speed spells high mileage with these"

GY6 150cc with 26,000 miles . . video review. High RPM downside.

Oil Change video. While positioned on the scooter center stand, warm engine dipstick oil level should be around midpoint on the cross-hatched tip when placed against the case threads (not screwed in). Since most GY6 China scooter engines only have an oil strainer screen, as compared to an actual filter element, it is important to initially change oil frequently to flush out suspended metal particles. WalMart SuperTech 15W-40 works fine for engine break-in, and after drain-oil "glitter" subsides, consider Delo 400 LE. RollingWrench recommends Harley V-Twin engine oil. Using a WalMart FloTool funnel may be helpful while refilling the oil.

WalMart SuperTech 80W-90 works fine in the rear gearbox. Using a plastic straw extension on the pointed-tip bottle cap may be helpful while refilling the oil through the bolt hole. Just "snug" tightness on the these bolts to avoid stripping the casting threads. Consider using pipe thread compound.

BMS scooter maintenance interval guidelines.

Engine temperature meter resource.

WalMart sells a metric wrench set that includes a 17mm for the bottom oil drain plug, and a 9mm for valve adjustments. A small cresent is also useful for turning the square adjuster. Harbor Freight feeler gauge.

If the scooter engine just "suddenly quit" or won't start, and you did not accidentally hit the emergency off switch on the right grip controls:
• Is fuel visible in the in-line filter? On gravity feed gas tanks (above rear wheel), shorten the supply line (if necessary) to eliminate in-line air gaps below the carb inlet port. Check if any vacuum or fuel lines are pinched by the under-seat tub or other panels. Emission valve issue.
• Has an overfilled gas tank caused a wet vent line element to block inlet air flow, stopping outlet fuel flow . . deficiency example.
• Is the screw in the end of the carb drain tube (above the center stand) missing?
• Is sparking visible at the spark plug tip when grounded against the engine case? When starting the engine, is there any ground arcing where there shouldn't be, such as connectors or wires? Is there a spark plug cap deficiency? Surging issue.

On some scooter models, a safety interlock prevents engine starting if the side stand is extended. A high-idle cold engine start will often turn the rear wheel, so scooters should always be started on the center stand.

If the electric starter will not energize . . in addition to above, most starter relay (solenoid) circuits have an interlock feature that requires pulling one of brake levers (brake light should illuminate). The low-amperage side circuit usually has a fuse, which is often located in the battery compartment on 50-125-150cc China scooters. If the battery is degraded, it may lack sufficient amperage to energize the starter at enough rotational speed to enable the bendix drive gear/clutch . . 50cc . . 125/150cc. 125/150cc starter O-ring deficiency.

Wet-Cell Battey (NOT sealed gel-cells) electrolyte may have evaporated to a level below the top of the individual cell internal plates. At your own risk, and with proper safety precautions . . remove battery and refill the cells with just enough water (distilled preferred in a pointed-tip squeeze bottle) to cover the plates. A significant key-off battery amperage drain may indicate the one-way regulator diode function is deficient . . or some other ground fault. When not in use, consider keeping the scooter battery connected to a float charger such as the WalMart Schumacher. Epsom salt rejuvenation technique . . related comment. New battery activation video.

Fuel, spark, and compression are required! One method to test for a start-up fuel starvation issue is to by-pass the carb by injecting a little gas directly into the intake manifold vacuum port with something like a medicine dropper, then re-connect the hose before starting the engine. Check float bowl level. Gel formation is a potential consequence of NOT draining the carb bowl prior to LONG TERM storage. For gravity-feed gas tanks (above rear wheel), the vacuum operated outlet valve can be tested by squeezing a pointed-tip bottle and connecting the vacuum line to enable fuel flow. NOT a good idea to suck on the valve vacuum line with your mouth . . to avoid injesting gasoline if valve internal diaphragm is defective.

One CV carb cleaning method is an in-place flush (some of the newer carbs are assembled with tamper-resistant fasteners). On a cold engine (when the enricher passageway is open), remove the diaphragm-slide-needle assembly. Applying Armor All (or similiar product) with a foam brush to the diaphragm will keep the rubber supple. While wearing eye protection, spray carb cleaner (aerosol can with nozzle tube) down the main jet. Temporarily rotate up the left-side L-shaped black carb bowl vent tube and plug, pinch, or clamp closed while pulse-spraying to force some of the solution through the low-speed jet and enricher passageways. Removal of the under-seat tub may be necessary for best aerosol can orientation. Several nozzle tubes can be connected with short sections of ball point pen ink tube. This procedure may wet the spark plug, so the engine may not restart for several hours . . unless the plug is removed to expedite airing-out the cylinder. To avoid this, the flush can be performed with the scooter on the center stand while the engine is running and diaphragm-slide assembly removed. As the throttle is opened to increase engine speed, pulse spraying carb cleaner down the main jet, to flow the mixture out of the low-speed port, will keep it running. Probably a good idea to change the engine oil following this procedure, in case any of the cleaning solution has worked past the piston rings and diluted the crankcase oil (routine periodic maintenance . . check valve lash, in-place carb flush, and change oil).

Carb Enricher (Choke) Switch Installation

Grabit screw extractor

Carb Cleaning Videos. Some low-speed jets have internal crosshairs . . location.
Green antifreeze and dedicated crock-pot method . . images.

Always check valve lash and cylinder compression (10mm adapter required) to establish a troubleshooting baseline . . guidelines.

One common "intermittent" gremlin is loose ignition coil connectors. Also continuity test the CDI to black coil terminal circuit to find any wire breaks under the plastic insulation near connector pin crimps. GY6 50/125/150 ignition coil Ohms test . . primary side 0.1~1 Ohms . . secondary side 2~4K Ohms with connector wire unscrewed (per page 59 of this manual). Coil issues.

Electric-Kick Starting Issues

AC-CDI or DC-CDI

Stator Ohms readings

GY6 Starter & Ignition Troubleshooting Video (25:42)

No Spark Troubleshooting . . obstructed gap . . crushed trigger pickup coil wire . . half-throttle stall. Ignition trigger pickup coil resources . . ScrappyDogScooters.

"What if there's a misfire at, say 1/2 throttle, but only under load? Carburetion can cause a miss that looks, acts, and feels exactly like an ignition miss. How do you tell the difference? Easy, Hook up a timing light. Use one of the types that does not have to be hooked to a battery for power, if possible. A lot of the old style lights were like this. Tape it to your handlebars and go for a ride. Look at the light. If the light looks bright and steady when the misfire occurs, then the problem is in carburetion. If it goes out when the misfire occurs, then the problem is with the ignition. There are all kinds of ways of doing this and you can use different tools, like plug caps with lights on them. The big thing is being able to see when the spark occurs... or doesn't occur." . . source . . eBay timing lights

Lost power issue . . sheared crankshaft-flywheel woodruff key . . location . . symptoms

Carb diaphragm-slide deficiency. CV carb fuel atomization video.

50cc (139QMB) head deficiency.

Dropped valve seat. Broken valve spring.

Securing exhaust pipe nuts.

High Octane Fuel

ScooterFocus Troubleshooting Articles:
Scooter Won't Start
Scooter Won't Run
Scooter Carburetor Adjustment

"Carb" conundrum

How To Tips

Carb cleaning videos . . 50cc . . 125/150cc
Carb jet sizes
Engine cleaning

Troubleshooting Flow Chart Guide

General information video.

Theft deterrent discussion (Las Vegas). Deterrent reviews . . BikeWorld . . Slate.
"I lost my Harley to theives years ago. It was chained with a solid Titanium link chain which the dealer said was about "cut-proof". He was right. BUT... theives sprayed the monster chain with freon, and hit it with a hammer. It shattered like glass, and the hog was history." . . oldchopperguy

Terminology video
Terminology glossary
China GY6 150cc engine service manual.
Manual resource.
GY6 Rectifier Pin-Out
Kymco manuals
Provoscooter manuals
Scooter Assassins manuals
GY6 125/150 cut-away image
Repair Manuals
Motofino Blog Archives . . Website
Haynes China Scooter Manual . . Amazon . . review
Assembly guideline resource
Scooter Therapy guidelines
Check battery, charging, regulator video.
Change clutch torque spring video
Honda Ruckus 50 service manual

China Scooter 50-150cc Valve Adjustment Guidelines
Cold valve lash . . 150cc .004 inches . . 50cc .002 inches
Cause & Effect . . 125/150cc cam-stopper issue
Compression Test Tutorial . . tester with 10mm adapter
Vacuum gauge troubleshooting guidelines
Coil On Plug Ignition
Spark Plug Readings . . Overview
4-stroke animation
Cylinder Combustion Video

How CVT Works Video . . Variator Service
150cc CVT Drive Belt Change Video . . be sure to insert a temporary spacer in the variator to prevent the rollers from dropping (which requires disassembly to position the rollers uniformly).
Belt Change Tips
Hard Starting, Loss Of Power . . variator roller issue
Clutch Assembly Video . . Removal Method

Capacitor Discharge Ignition Module
Troubleshooting guidelines
AC-DC module comparison image . . video
ScooterWiki
ScrappyDogScooters . . DC-CDI
Monster GY6

Excessive Oil-Consumption/Blow-By Issue
Air Filter Fluke
The Usual Suspects
Tank Venting . . Vent Obstruction Issue
Fuel Filter Location
Fuel Filter Issues
CV carb fuel flow reference diagram
CV Carb Discussion
Torn Diaphragm
Broken Slide Needle E-Clip
Missing Slide Needle E-Clip
Carb Drain Tube Issue
Vacuum Leak Detection
Idle Issue (cracked carb mainfold)
Loose Intake Manifold
That's Why It Won't Idle
Intake Manifold
Dielectric Application
Fuse Continuity
Fusebox Continuity
Backfiring Under Acceleration
Backfire On Deceleration
Charging Grounding Issue
Starter Brush Continuity . . Starter Teardown
Monitor Muffler Clamps . . Heavy Duty Options
Oil Coming Out Of Fill Spout
Gearbox Seal Replacement
Engine Knock
The Truth About High Octane Fuels
Octane rating
Fueling Faux Pas
Water Decarbon Method
Typical China 150cc Scooter wiring diagram
Chinese scooter ABS Demystified
Brake Light Always On
Running with no battery may damage voltage regulator.
Oil Cooler
LaVie (and similar) Carb Controller . . JCL parts reference
Canister Vent Restriction
CDI & Coil Comparison
125/150cc Kick Start Gear Removal

Some mirror designs have an adjustment tension screw under the back cover. Attaching a section of hose may also limit travel.

Potential tire valve stem issue . . video.

Carb Low-Speed Mixture Screw Extension

Oil Cooler Discussion . . Babel Fish Translator



139QMB 50cc 4-Stroke
Irrational Exuberance . . Delusional
Potential tamper-resistant elements . . no-head carb screws . . intake manifold 5-sided nuts
Replacement engine
139QMB Manual
GY6 Rectifier Pin-Out
Maintenance Guidelines
14mm Carbs
CVT drive video
Belt replacement video
Belt change technique
Variator changeout images
Maintenance Manual
Carb Exploded Diagram
Cutaway Images
Loss of speed variator issue.
Variator removal image . . video
Elusive rattle.
Fuel Flooding Into Crankcase
Warm engine electric starting issue
Missing Carb Needle
Peace engine failure
63cc marking indications
Big Bore Kit longevity
Big Bore Kit excessive compression
Big Bore Kit balance & bearing issues
Big Bore Kit head valve length variation
Racing Cam secrets
Fuel gauge dissolved tank float issue
Starter Push-Button Switch Failure
Aftermarket Final Drive Gears
Idle/Pilot Jet Crosshairs
Gravity Gremlin
Intermittent Rattling Noise
Head Sparkplug Thread Issue


NO SPARK TROUBLESHOOTING

Verify that the spark plug wire ends are securely twisted into the screw studs in both the plug boot and coil. Check continuity of CDI-to-coil wires, and engine-to-frame ground wire. Some multimeters have an audible tone continuity feature . . example.


"i suspect that there was an intermettent spark due to dirt from the stator and flywheel" . . thread link

”that spark plug wire and braided metal hose seem a little chummy” . . thread link

”the wiring harness was getting pinched between the frame and the floorboard!! This was grounding out the ignition or power to the CDI box” . . thread link

”Put some crushed ice in a plastic bag. When you have a no spark situation chill the CDI or the coil, and see what happens. Do them one at a time.” . . thread link

”Pin plugs are jsut holders for individual small electrical connectors, and sure enough one of the connectors had backed itself out.” . . thread link

”The first thing you should try is to disconnect the black/white wire from the CDI connector and then check to see if you get a spark. This test will indicate if the problem is with ignition components or in the scoot wiring. With the black/white disconnected and you still do not get a spark, the problem is within the ignition system component parts. If you do get a spark, then the problem is with the ignition switch, kill switch, sidestand switch, or the wires going to those switches.” . . thread link.
A miniature flat-tipped screwdriver can be inserted into the plastic housing to bend down the tang for temporary ground wire connector removal.


”The lesson I learned from all of this is that you can't determine anything by measuring voltages out of the stator with the CDI hooked up.” . . thread link.

Ignition Troubleshooting: No Spark

CDI Troubleshooting

”Ive tested a stator before that ohmed out fine but after it ran for a while it lost spark because of low quality windings.” . . thread link.

Replacing the GY6 150cc stator requires first removing the shaft nut (lefty loosy) with an impact wrench, or securing the flywheel with a strap wrench and using a socket wrench/bar, then attaching a 27mm x 1.0mm left thread puller to remove the flywheel. Replacing the 139QMB 50cc stator requires removing the flywheel with a 24mm x 1.0mm right thread puller. The scooter panels may obstruct the use of the combination 50cc/150cc cross puller design, but a 10mm bolt from a hardware store can be substituted.


GY6 ignition trigger pickup only . . Scrappy Dog Scooters

[earlwb]

well for me, one problem was setting the engine idle speed too slow. I found that if I let the warmed up engine idle at about 1800-2000 RPM that solves the engine stalling while it is warming up and the automatic enrichener is disengaging. I have seen a lot of people adjust for a lower idle speed of around 1200 rpm or so. Which actually works if the engine is warmed up good, but not when it is still cold though.
Another problem is on my scooter they have a carbon canister for recycling gas tank vapors. If you over fill the tank, the excess fuel overflows into the canister, causing the fuel tank vent to not work right. The engine will run OK for a while until a slight vaccuum builds up in the tank and then the engine dies on you quite suddenly. Loosening the gas cap for a while cures this problem until the carbon canister clears itself out.
At another time, I had the engine suddenly did not want to idle even when warm. I had to set the idle speed to max to get it to idle. But as I rode around trying to get home, the idle speed started increasing and increasing, so every few miles I had to stop and readjust the idle screw some to slow it down. About 20 miles later it was back to normal again. yes I had accidentlaly overfilled the fuel tank again. So it must have been flooding out the engine once more via that carbon canister thingie.

Anyway, if it ever stops raining around here in texas, I plan on installing a aluminum intake manifold and a K&N air filter, and ripping out all this extra anti-smog crap they have on my scooter. All that junk just looks like more trouble and problems waiting to happen to me.

[beaugator]

Tell your guys to make sure the fuel line is not touching the frame or going vertical anywhere. The fuel lines will vapor lock just as easily as the tank will when the fuel gets hot and vaporizes in the line.

[Yankee Rebel]

I recently purchased a Roketa MC-54-250B and the "Owner's Manual" says to use 10W / 30 oil in the gear box. I saw a video online that says to use GL3 gear oil. When I checked on that, it says GL3 is usually 85W / 40 and the only thing I could find close to that is 85W / 140. Does anyone know if that is safe to use in the gearbox of my Roketa? The 85W / 140 is GL3, GL4 and GL5 rated. I have changed the engine oil and have ridden about 30 miles on the new scoot, using the gear oil and coolant that was in it, but want to change them out as well. Any help on the gear oil question would be greatly appreciated.

[harrywr2]

The weight of gear oil and motor oil is measured differently.

A 10w/30 motor oil is about the same as a 75w/90 Gear Oil. Engine oil and gear oil are subject to different stress.

[stever777]

Your statement about screw in the end of the carb drain tube is interesting. My scoot stopped today. If I try to start it, 2 seconds later gas comes running out the drain tube fixture.

However, the opening might be 6mm, then after about 1/2" it looks like 2mm. Can't tell if the 6mm part is threaded or not.

Do I just get a 1/2" 6mm metric screw and some loctite? It's freaking me out that after 150 km this thing falls out and I just freakin' come to a stop!

Thanks!

[harrywr2]

Jun 18, 2009 0:23:58 GMT -5 stever777 said:

Your statement about screw in the end of the carb drain tube is interesting. My scoot stopped today. If I try to start it, 2 seconds later gas comes running out the drain tube fixture.

However, the opening might be 6mm, then after about 1/2" it looks like 2mm. Can't tell if the 6mm part is threaded or not.

Do I just get a 1/2" 6mm metric screw and some loctite? It's freaking me out that after 150 km this thing falls out and I just freakin' come to a stop!

Thanks!

The end needs to be tapered a little so it will seat correctly..i ended up using a 6mm x 1/2" metric set screw which cost me all of 70 cents at Ace Hardware with a bit of loctite...or you can order the correct screw from partsforscooters.com ...$3.99 plus shipping.

Or you can disconnect the hose from the fitting and stuff a golf tee into it.

[stever777]

Thank you so much! A bit stunned that this stopped me cold in traffic and was rather dangerous.

THANK YOU!

[spaceball1]

I have a roketa mc-07-150, was riding home doing 40-45mph and had a quick surge in power then almost die out. pulled over and engine ran fine in idle but whenever put gas to it anything over 4000r's would lug out the engine could go no faster than 15-20mph, I put a new gas filter on, new intake manifold, spark plug, changed the gear and regular oil, cleaned air filter, checked all the fuel and vacuum lines and everything is snug just wont move me. any ideas

[Danny's Scooter Shop]

Jun 22, 2009 16:44:12 GMT -5 spaceball1 said:

I have a roketa mc-07-150, was riding home doing 40-45mph and had a quick surge in power then almost die out. pulled over and engine ran fine in idle but whenever put gas to it anything over 4000r's would lug out the engine could go no faster than 15-20mph, I put a new gas filter on, new intake manifold, spark plug, changed the gear and regular oil, cleaned air filter, checked all the fuel and vacuum lines and everything is snug just wont move me. any ideas

I would check for an exhaust restriction. if none is found then check the diaphragm in the carb for a rip..

[kuzikood]

sounds like a vacum line fell off odr airfilter or some thing sudden rev means it went real lean real fastr

[franktank]

Umm, i would say go to basics.... Check fuses first.. Check fuel, and check batt. connection. Fuel, + Fire, + Good compression should equel a start. Unless yer starter don't work.. in that case, hit it with a hammer and see if that don't get it rotating again..

[gmoney]

A little late on your reply, the post is dated many moons ago!


Gary

[reddog]

Have a question on gy6 engine and not starting. I've replaced the stator and fly wheel, ignition coil
CDI box, and I still have no spark at the plug. Need help

[sprocket]

Welcome new Dawg!!

Best if you make a New Thread and re-post this.

Question, When you replaced the stator, did you also replace the pick-up coil that is located on the outside of the flywheel at about a 11o'clock position?

If that is fault you will never get a spark...

A new pick-up coil should have come when you purchased the stator...

[reddog]

I did put a new pick up coil on with the new stator, and it is in the 11 o clock position

[sprocket]

How are you testing the spark plug? Try another plug?

You must hold the metal part against the engine.

Clean a part of the frame with sand paper to bare metal. Then try holding the metal part of the plug, against the frame and run the start to see if you have spark.

If you get spark on the frame but not on the engine then you have a bad engine ground wire. This is a green wire attached to the engine usually above the fan on the curb side.

Other than this, you need to get a multimeter and start testing electrical circuits.

Replacing parts is an expensive waste of time...

[tazmo8448]

great article and have definitely bookmarked this one for future use...thanks this is what this site is all about

[ChroNickolas]

PLEASE HELP!!

I have a brand new 50CC GY6 engine. I had a 72cc Big Bore kit (50mm instead of 47mm so I'm told) that I put into the new engine before I started it.

I KNOW THAT WAS MY MISTAKE RIGHT THERE. BEAR WITH ME

I put all the parts on as I was told by online forums and my mom's boyfriend who fixes all motors (boats, cars, motorcycles) but when I went to fire it up. The starter usually kicks like 3 times a second with the *ching ching ching ching* but it was only doing like 1 a second and it sounded very slow. No kick over, no nothing, just the engine slowly rotating..

So I took it to a shop who now tells me I have an oil leak somewhere and the 12v 4 amp battery I have might not have the power I need.

THIS HAS BEEN A YEAR AND A HALF OF HELL. NEW ENGINE SHOULD WORK!! PLEASE HELP!!!

[igor]

May 18, 2011 15:21:04 GMT -5 ChroNickolas said:

PLEASE HELP!!

I have a brand new 50CC GY6 engine. I had a 72cc Big Bore kit (50mm instead of 47mm so I'm told) that I put into the new engine before I started it.

I KNOW THAT WAS MY MISTAKE RIGHT THERE. BEAR WITH ME

I put all the parts on as I was told by online forums and my mom's boyfriend who fixes all motors (boats, cars, motorcycles) but when I went to fire it up. The starter usually kicks like 3 times a second with the *ching ching ching ching* but it was only doing like 1 a second and it sounded very slow. No kick over, no nothing, just the engine slowly rotating..

So I took it to a shop who now tells me I have an oil leak somewhere and the 12v 4 amp battery I have might not have the power I need.

THIS HAS BEEN A YEAR AND A HALF OF HELL. NEW ENGINE SHOULD WORK!! PLEASE HELP!!!

I would suggest you to create a new thread for this... replies on this kind of posts usually is "great job" or simular....

[igor]

This is a typical "sticky" post...
Can an Admin please make this sticky.......

[kanastigu]

i found the site extremely useful. i did have a question though.

""Replacing the GY6 150cc stator requires first removing the shaft nut (lefty loosy) with an impact wrench, or securing the flywheel with a strap wrench and using a socket wrench/bar, then attaching a 27mm x 1.0mm left thread puller to remove the flywheel. Replacing the 139QMB 50cc stator requires removing the flywheel with a 24mm x 1.0mm right thread puller. The scooter panels may obstruct the use of the combination 50cc/150cc cross puller design, but a 10mm bolt from a hardware store can be substituted.




Read more: scootdawg.proboards.com/index.cgi?board=talk&action=display&thread=4483#ixzz1Sp9TKFIn""

The 27mm will fit any 150 scooter?
also I'm hoping the tool comes with instructions on how to use it.
And when i say this site was helpful, lets just say my fingers are quite happy to know there is a tool for this job.

[h3nry]

"Worst Case Scenerios image gallery" the link is dead and lead me to a facebook impersonation
they removed it

[ledbet220]

has good gas good spark acks like out of time but doset seem to be what could it be

[sprocket]

valve gaps?

[harvickcrew]

i have a 2008 roketa mc-16-150.I was riding and all of a sudden id stalled and then it started going again now i have a oil leak at the valve cover vent.how do i fix it?

[sprocket]

How much oil do you have in it? You should only have 3/4 of quart or 750 ml to be exact

[cobrahd1999]

Jun 30, 2007 16:20:51 GMT -5 earlwb said:

well for me, one problem was setting the engine idle speed too slow. I found that if I let the warmed up engine idle at about 1800-2000 RPM that solves the engine stalling while it is warming up and the automatic enrichener is disengaging. I have seen a lot of people adjust for a lower idle speed of around 1200 rpm or so. Which actually works if the engine is warmed up good, but not when it is still cold though.
Another problem is on my scooter they have a carbon canister for recycling gas tank vapors. If you over fill the tank, the excess fuel overflows into the canister, causing the fuel tank vent to not work right. The engine will run OK for a while until a slight vaccuum builds up in the tank and then the engine dies on you quite suddenly. Loosening the gas cap for a while cures this problem until the carbon canister clears itself out.
At another time, I had the engine suddenly did not want to idle even when warm. I had to set the idle speed to max to get it to idle. But as I rode around trying to get home, the idle speed started increasing and increasing, so every few miles I had to stop and readjust the idle screw some to slow it down. About 20 miles later it was back to normal again. yes I had accidentlaly overfilled the fuel tank again. So it must have been flooding out the engine once more via that carbon canister thingie.

Anyway, if it ever stops raining around here in texas, I plan on installing a aluminum intake manifold and a K&N air filter, and ripping out all this extra anti-smog crap they have on my scooter. All that junk just looks like more trouble and problems waiting to happen to me.

Put a manual choke on not that hard..Makes life happier. lol

[cobrahd1999]

May 10, 2009 10:06:49 GMT -5 Yankee Rebel said:

I recently purchased a Roketa MC-54-250B and the "Owner's Manual" says to use 10W / 30 oil in the gear box. I saw a video online that says to use GL3 gear oil. When I checked on that, it says GL3 is usually 85W / 40 and the only thing I could find close to that is 85W / 140. Does anyone know if that is safe to use in the gearbox of my Roketa? The 85W / 140 is GL3, GL4 and GL5 rated. I have changed the engine oil and have ridden about 30 miles on the new scoot, using the gear oil and coolant that was in it, but want to change them out as well. Any help on the gear oil question would be greatly appreciated.

I use Amsoil 10w40 motor oil great stuff been using it for years in my Harley lawn equipment and all my cars never an issue. Bel-Ray 85/90 in the gearbox. Red Line makes great products to.

[cobrahd1999]

I just want to make sure that the engine is a GY6 so here goes Qlink 2008 Siena 150cc yes or no. Second question what size carb I see some good carbs at a great price thinking buying some spare parts to have around while the price is right. But the owners manual states nothing on both so that's why I am asking these dumb questions sorry.lol
thanks guys for any help.