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American Legion Rider
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Discussion Starter · #1 ·
This thread is the start of a compilation of common problems and fixes being undertaken by Miss Mercedes. So let's let her shine as this is something this site has needed for a long time. A one place to go sort of thing. I've turned this into a Sticky so it's the first thing someone looking for answers will find. It's all yours Miss M. Good luck might be in order as I see this as a major undertaking.
 

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Moderator - Loves All Motorcycles
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Suzuki C90 Boulevard

So I'd like to start this off with the thread that inspired this. Do bear with me as I may or may not change the format for easier reading/better troubleshooting.

Suzuki C90 Boulevard that wouldn't start after an oil change. No spark.

So, I changed the oil & filter on her bike. Hit the starter and it fired up immediately. Great!
Except it died after about 20 seconds. Attempts to restart it result in it turning over, and over, but no start!
So far my trouble shooting has discovered that neither plug is generating a spark.

As this is happened to both at the same time, I don't suspect coils or such but I checked all the fuses - all good. Pulling the plugs, I detected that it is getting fuel.
The eventual fix?

https://www.motorcycleforum.com/59-...-need-help-fixing-motorcycle.html#post2559576

...he determined that the problem was an absence of signal from the "trigger". Basically, it's a signal from the generator, which identifies the location and when to "trigger" a spark to each cylinder.

He took the cable back to his shop and repaired it. Then returned it and reinstalled it..........and it works!!!
That wire in question is the pick-up coil from the CKP (Crankshaft Position Sensor).
 
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Chinese Scooters: CF Moto Fashion 250, 150cc Ruckus clone, Bashan MC-16-150T

This next one features problems I experienced myself with three different Chinese scooters, a CF Moto Fashion 250, a Cixi Kingring Motorcycle Jinlun Ruckus clone, and a Bashan MC-16-150T.

A quick note before continuing is that Chinese clone motorcycles are all very very very similar. So even if you do not own a model I just listed, these fixes will likely work for you. These can also work for Grom clones that aren't starting.

The Bashan MC-16-150T was a brand new scooter that sat for ten years. These scooters are sold under maybe 100 different brand names and models, but they're all the same inside. I got it a brand new carburetor, got it a brand new battery, then got it to fire on starting fluid (ruling out spark plugs), but it would not run.

The solution? The tank was so rusty that it needed replacing. The new owner had the scooter running in less than an hour after I sold it to him using a new tank.

The next scooter I picked up (the Ruckus clone) hadn't run in two years and didn't start. All it needed was a battery and a new carburetor.

https://www.motorcycleforum.com/226-scooters/228230-gambler-500-project-imperator-slowiosa.html#post2533872

And finally, my CF Moto project:

Acquired in November from a fellow Gambler 500 team member. I replaced the battery, the carburetor, and learned the starter solenoid was installed backwards by a previous owner. It sat for roughly two years without running and I made a gamble that I can make the old fuel burn again. While I was successful in that, I made two critical errors:

1. I didn’t replace the fuel filter.

2. I rode it every day for a month, not really ever allowing it to get to running temperatures.

Despite that, the scooter was good for 75mph, impressive acceleration, and it all around it ran absolutely perfectly. I felt I had myself a good score and with actual fresh fuel I’d probably even break 80mph. I proceeded to daily it for a month, taking it everywhere.

Fixing my Original Mistake

I made sure I ran all the bad fuel out of the tank and made sure the tank wasn’t rusty. Then I filled it with good fuel.

I then replaced all the fuel lines, the fuel filter, and the carburetor. I then installed a pod filter. I also closed off the crankcase vent to the airbox. Instead, the crank vents out into the outside. The original problem with not being able to start after getting hot remained, but at least I was no longer fouling my air filter and carb with particulate matter (air filter material) and oil. Top speed was about 40. Figured I would get more speed from restricting the pod filter, but first I really wanted to address the problem with not being able to restart with a warm engine.

Take Three

I decided to replace basically everything else I didn’t touch. I took the panels off and replaced the air filter so I can ditch the pod filter and go back to the factory setup (I still have the crank venting to the outside, though) and not have to jet the carb. Then I replaced any old vacuum lines that remained. All this work resulted in no change. It does cold starts well, but introduce any heat and it’s dead. The engine tries to fire, but it just won’t.

You can get it to start on starting fluid, and then it will go on to run like it’s misfiring and it’ll die as soon as you stop moving...then fail to start again.

Only thing I haven’t replaced is the spark plug (because the bloody thing has a spark plug that requires a bigger socket than the one I have for my smarts), but I fear it’ll be a waste of time.

Is there anything else I’m missing or do you think the spark plug will be my magic bullet?

This was supposed to be an easy project, but it certainly has taught me a lot about motorcycle/scooter repair! If the spark plug doesn’t fix it I’ll probably get rid of it. I’m just not sure how much I would be able to trust it at that point..And I'd hate to do that because when this thing was running well it was an awesome way to get around. 75mph top speed and everything.

For a TL;DR - here’s everything I replaced:

- Battery
- Fuel Lines
- Vacuum Lines
- Carburetor (built in electric choke)(2 times)
- Air Filter
- Fuel Filter
- Oil
- Fuel

Only thing I can think to replace now is little sparky..
The eventual solution? Valves needed adjusting and a new spark plug coil.

I did it!!!

Not only did I get the CF Moto running again, but I cleared a new GPS top speed!

Here’s what happened:

First thing first, I started the scooter to get a baseline. It took a LOT of starting fluid and when it did get going it puffed out enough white smoke to compete with a steam locomotive.

I decided to change the oil since the oil it had already was pretty thin. This scooter has the easiest oil change ever!

After getting the engine warm, I changed the spark coil. I also found out that the spark plug was gapped way too close.

This resolved the issue where it wouldn’t start hot. Now it starts hot... barely. It still ran like garbage, so I considered the coil to be a factor, not the cause.

Next, I located the CDI. It was ahead of the battery tray and on top of the fuel tank. Unfortunately the CDI I bought was the wrong plug configuration even though I ordered the correct one... thanks, Amazon! I crossed my fingers that the CDI was good and moved on.

Next up, I found the valve adjusters.

Since the clone's engine is basically the same thing as Honda's engine, I decided to follow Honda’s instructions for mechanics..

(This image is hosted on my blog, so it should remain up indefinitely)



Unfortunately, I couldn’t get the scooter to start and stay running without the engine making horrifying tapping noises. Meanwhile, the scooter still spat out white smoke. Whenever I adjusted the valves to a position without the tappet noises, the scooter would die and not start without a lot of cursing in Mandarin and starting fluid.

I was just about to throw in the towel when I decided to go for broke. I took the carb from my first resurrection of this scooter and gave it a thorough cleaning. Considering the carb it currently has was brand spanking new without even a mile on it, I figured I was wasting my time.

I installed the carb from the first resurrection and gave it a go. It started without starting fluid this time and when I adjusted the valves properly? It ran even better. Within a minute the white smoke cleared up as well.

I reluctantly took it on a test ride, but the little thing blew me away. It seems to perform even better now than the first time I resurrected it. I hit a GPS verified top speed of 80 mph. Not bad considering I’m not at all lightweight.

Uh...well... unfortunately this means that I want to keep it. This adventure has taught me so much about this scooter that I’d feel bad giving up on it after this victory. It also doesn’t help that even running I won’t be able to make my money back on it. So screw it!

https://www.motorcycleforum.com/59-motorcycle-repair/232868-my-eternal-project-scooter-refuses-live-any-ideas.html#post2558028
 

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Easy Valve Adjustments on Honda Scooters and Chinese Clones

For scooters: If in the case you're getting fuel, you have spark, check your compression. You may need to adjust your valves. Poorly adjusted valves can cause poor starting or no starting. Many Chinese Honda clones come with valves that are far too tight, while an old Honda may have valves that are far too loose. In either case, the manual's procedures for adjusting valves is a lot of work compared to what Honda tells their mechanics to do. This works on any Honda and Chinese clone with valve adjusters on top of the engine. You may need to do an initial adjustment just to get the engine to run, then fine tune once the engine is running on its center stand.

From: #5 CH250 Valve Adjustment

And in case the link goes bad:

What Honda Told Their Mechanics To Do: Adjust the valve clearance while the engine is WARM and running. With the side access panel removed to allow access to valve adjusters, run engine to normal operating temperature.

With machine on center stand or supported and idling, (increase idle speed slightly to prevent stalling) work on each adjuster in turn, loosen the adjuster quadrant clamp bolt and move the quadrant inwards a little (the motor will start to sound "tappety" ((valve clearance increasing)) followed by slowly moving the quadrant outward whereby you will notice the engine will become quieter (valve clearance decreasing).

When you reach the point that there is no tappet noise, hold quadrant in place and re-tighten clamp bolt.

If you go too far normally a misfire will appear or the engine stalls, the reason for increasing the idle speed.

A slightly loose tappet is less harmful than a tight one. (courtesy, Steve, Honda mechanic, Honda UK, post 2041, Twist-n-Go Scoot)

So, back to the original question--why the discrepancy in the intervals of valve maintenance of similar engines?

When the service manuals were written production of the Honda CH250 and Helix CN250, which share the same basic driveline, had not commenced.

Honda used relevant sections from earlier manuals to piece together the manuals of those bikes.

Additionally, clearances in prototype models were different than tolerances in production machines.

What mechanics discovered was that the second method was more successful being that the lifters are mechanical, not hydraulic.

Several Honda mechanics I talked with favor adjusting the valve clearance if the lifters are noisy and leaving them alone if they are quiet regardless of the mileage.
After having done this myself, you don't even need to open the side cover if your hands and tools are small enough.
 

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2005 Suzuki GSX600F Katana

In this situation, we have a Katana that wouldn't even turn over when the start button is pressed.

I started it up a few days ago, went to put it in first gear from neutral and it shut off. It would not start up there after. The battery is fine, tested and it is at peak power. Lights are working, dash lights working, but the engine will not turn over or even make a sound when I try to start it up now. I popped the clutch in second gear after 5 days of the bike sitting from this problem and it ran fine, so it is receiving power, but the bike won't start up or even turn over from the starter button.
The solution?

https://www.motorcycleforum.com/59-...-bike-wont-start-battery-fine.html#post645001

...my starter relay had gone bad, not too expensive or extensive of a repair. So all is well, back on the road
 

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2007 Yamaha XV1700 Roadstar

Surprisingly it's getting harder to find issues where the original poster comes back to report good news. I'm seeing tons of great advice, but hardly seeing the end result.

In this scenario, we have a 2007 Yamaha XV1700 Roadstar not starting after jumping the battery.

I recently jumped my battery and then the bike wouldn’t start (pretty sure I fried something in the process....dumb move I know) I then charged the battery for awhile and I went to turn the bike on and the lights and everything came on fine but when I push the ignition button absolutely nothing happens. Not even a click from the starter relay. When I bypass the relay the bike turns over - so I thought the relay was bad. I put a new relay in and still nothing. Is my ignition fried? Or what else could be the problem?
Jumping a bike can be risky, especially if what you're using to jump your bike is a running vehicle. You may be fine, or you may fry something as seen in this problem's solution!

https://www.motorcycleforum.com/59-...rn-over-but-has-full-battery.html#post2533268

Thanks everyone. I did check the fuses and one is blown. Honestly feel kind of dumb for not checking them before but good learning curve. I will replace it and see if the problem is fixed and will update this thread.
Thanks for all the help!
 

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1982 Suzuki GS850G

I forgot about my other non-starting bike!

Back around the time I joined the forum last year I had sold my Honda Rebel and replaced it with a Suzuki GS850G (G stands for shaft drive). I rode it about 100 miles, parked it, then when I tried to start it the next morning it ran, rode, eventually sputtered to a stop, then wouldn't start for the rest of the weekend.

Using muscle memory, I accidentally set the petcock to Reserve (I wasn’t aware of this). I made it 1 mile before the bike stopped being able to exceed 6k rpm...****. I turned around and tried to get back home.

At 1.8 miles it straight up died. I looked down and discovered I had the bike set to Reserve. Oops.

I turned the petcock to “on” then tried to set off. It would only start with a flick of the throttle and the most RPM it could achieve is 1.5k and if you let off the throttle it immediately dies. Well, considering I was in the middle of a road without a shoulder, that was good enough to limp me to an area that was safe.

I then thought maybe the fuel gauge sucked so I wheeled it to a station and filled up. No vice, it occasionally would go to 5k and immediately die. All the while there was a little bit of gray/white smoke coming out of the exhaust.

What the heck? Did I flood the engine or something? I’ve read that if you never use the Reserve that there could be water/debris in it, is there any accuracy to that?

I walked it home and took the Buell to work. Hopefully it wakes up when I get home.
The solution was to just let whatever it was I sucked up to evaporate. The bike continues to run wonderfully today. As for the restoration, I just left it as-is as I kinda fell in love with its "daily rider" patina. :)

https://www.motorcycleforum.com/59-...kind-bike-its-already-broken.html#post2527898

Update: I got the GS running!!!

My hunch about it having sucked something other than fuel must have been correct. It purrs like the ugly kitten it is. Now off to restoring it!
 

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My wife's Vulcan 500

Hey everyone, I've read a lot of posts and tried a lot of things, but my wife's bike STILL won't start -

1) It's not the battery. It's been on the BatteryTender, voltage tests ok and it cranks, BUT

2) It coughs once if I'm lucky, then it's that annoying cranking-not-firing noise.

I figured out how to take it all apart, put in new spark plugs, put it back together, put gas back in the tank, hit the start, and -

ARGHHHH!!! :confused:

I should start it, ride it to the shop, and let them figure it out, but NO - :mad:

Sympathy is appreciated, helpful advice is even better - THANKS!

At least I got to buy a new spark plug socket
 

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Moderator - Loves All Motorcycles
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I've been having problems finding resolved cases on this forum. A lot of people take the advice then disappear. So if we resolve this I'd love it if you reported back.

I know your feel, I've had a lot of bikes cough but not start. But you know what? That just means you're close to getting it started!

Alright, so what bike are we dealing with here?

First thing I'd do is narrow down possibilities. What happens when you use starting fluid?
 

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It's a 2007 Kawasaki Vulcan 500 -

I haven't tried starting fluid. With a mower, you pull the spark plug out, spray that in the cylinder, put the spark plug back in and BOOM!

It's no easy feat to pull a spark plug on THIS thing! Drain the gas tank, take it off, yadday yadda etc. etc.
And I had 'routine maintenance' done, by the shop, last spring - you'd think it would start up again THIS spring, right?

Now my V-Star, that starts up just fine, but this Vulcan's gonna drive me crazy
 

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Retired twice: Navy and as a govt contractor
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Did you winterize it over the winter? Do you use any gas stabilizer? How old is the gas?
 

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I THINK I gave it Sta-Bil last fall - but I just had to empty the tank to get at the spark plugs. Some of that gas went back in the tank - top it off with fresh gas? Maybe I'll just shoot the damn thing - she doesn't ride it too much anyway :p
 

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I would get rid of all the old gas. fill it with fresh and some carb/injector cleaner. Double the the amount suggested. Crank it long enough to get it into the carbs and then let it sit. check the rubber boots mounting the carb(s) to the engine. Make sure they are tight, no cracks and not leaking. Try starting it again. Sit and repeat every couple of days. Check the air filters make sure they are clean . That is where I would start.
 

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For starting fluid, I just shoot it into the carb from the air filter side. If it fires, you have a fuel problem (likely old fuel and potentially dirty carb). If it doesn't fire, I'd be looking at potential spark issues.
 

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Discussion Starter · #16 ·
I'd also use carb cleaner rather than starting fluid. Starting fluid is for diesels. Carb cleaner does the same thing with gas engines without the chance of blowing something up. And Miss M is correct with shooting carb cleaner now instead of starting fluid into the air breather. If you already have starting fluid, just be very careful how much you use. Just a quick little shot. Carb cleaner is so much safer though and you are helping clean the carb some while you are at it. If it's going to fire it will. Critter has a good suggestion with a double dose of something like Sea Foam or Starbrite Star Tron Enzyme Gas Treatment, although in this case Sea Foam is probably best.
 

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Thanks man - you folks are awesome...

Today, it STARTED - and ran for about 10 seconds. I'm letting the carb/injector stuff do it's thing.

Maybe tomorrow it'll run for 30 seconds. Maybe more....
 

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Huzzah! Yep you have yourself a fuel issue. Once those carbs are clean you'll be ready to rock. :) If you want to expedite this process, shoot carb cleaner into the carbs. If the carbs are easy to remove, remove them and give them a carb cleaner bath. After 24 hours the bike should run nice and smooth.
 
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