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Discussion Starter · #1 · (Edited)
Been having a lot of "fun" trying to get my 2005 Tw200 started.

I have a video of me trying to start it

5558miles

Replaced the coil and spark plug
Checked spark (bright white)
Checked relay assembly (checked it on another bike)
Checked rectifier (checked it on another bike)
Checked fuel
Checked oil
Checked solenoid
Checked fuses
Cleaned carburetor 5 times and checked it on another bike and works
Battery charged and using a car battery to give additional power

Kickstand sensor was spliced together might be the issue?

CDI gives spark but may be bad?

Choke doesn't seem to change anything either, sometimes backfires


No idea why it's not kicking over to start

If anyone has any idea what it could be please let me know.


Other bike I tested the stuff on was a Kawasaki Eliminator 125cc , everything from the TW worked fine on it as well
 

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Welcome to the forum!! :D

Usually when the choke doesn't work as it should, it's a strong indicator that the pilot jet isn't clean enough or is still clogged up.
 

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Try a snort of starting fluid, This will rule out spark and timing or Carb issue.
Maybe your intake boot is torn and sucking air NOT getting to carb,
What temp in garage?
I see petcock on "on" How much gas? Try it in "Res" ?
 

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Discussion Starter · #6 ·
Welcome to the forum!! :D

Usually when the choke doesn't work as it should, it's a strong indicator that the pilot jet isn't clean enough or is still clogged up.
thanks, been using all the forums on trying to fix mine and to no avail finally decided to just ask for some help

Cleaned the carb 5 times and made sure its clean, used a wire to make sure as well with the help of carb cleaner and even wd40. my other bike also started and ran with it so i doubt its a carb problem anymore but still suspicious of it.
 

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Discussion Starter · #8 ·
Remove the sparkplug and squirt a little gas into the cylinder, replace the plug, and then see if it will fire.

Try a snort of starting fluid, This will rule out spark and timing or Carb issue.
Maybe your intake boot is torn and sucking air NOT getting to carb,
What temp in garage?
I see petcock on "on" How much gas? Try it in "Res" ?

Did you confirm the petcock is flowing?
The Petcock lets a lot of fuel out which I've figured out since the first few times I forgot to close it and was smothered in gassy hands, tried it in res as well.

the intake boot is fine, no cracks or anything distinguishable, took it off to make sure.

I tried starting fluid from the filter end off and got some pretty nice fire (not starting just a fire) I also tried putting starting fluid, carb cleaner and gas into the cylinder and nothing changed except a very loud backfire sometimes. Without trying those too I get gas into the cylinder since I can smell it in and on the spark plug, tried messing with the fuel/air mixture valve to flood the cylinder and it did so I'm very certain fuel is getting into it.

I'm not sure about timing yet

Temperature is around air temp 30f to 40f its not ideal temps but it is winter (Philadelphia)
 

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Discussion Starter · #9 ·
If they are tight, you will lose compression. It may push start if you can get the revs up a bit higher if the valves are slightly open. I wouldn't of thought this is the issue with the Km's showing on your odometer but you have checked all the other stuff...
It's getting good compression from what I can tell without a compression tester, when I messed with the Fuel/air mixture valve to flood the cylinder it shot out the fuel. Even before messing with the fuel/air valve it blew a lot of air out of the cylinder, ill still check them though. push starting also helped a little more. Got it started for maybe 2-4 seconds before dying out but its a little harder to do since the clutch is sticking and wont release since its been sitting a while.
 

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Wow!
Carb works on another bike. That's big deal. Eliminates a lot right off the bat.

Valve clearances has been mentioned already, but valve timing might be at issue. Maybe your valve chain jumped a tooth. It's fairly easy to check. I'll leave it up to you to research how rather than step through the process.

Bad fuel? If you haven't tried fresh gas, you can drain, flush and fill with fresh fuel.

BTW, as long as the bike is in neutral, the kickstand switch shouldn't matter.

Kill switch on the bars may be an issue, but since you have spark, I wouldn't think so. But still, I'd check it out or bypass it by unplugging from the harness.

Did you verify fuel fills the bowl on the carb by turning the drain screw and verifying fuel flows out the bowl? I ask this because I accidentally put the fuel line on the wrong nipple on the carb. Try putting a hose on the fuel nipple and blowing on it to verify fuel is able to get past the float valve assembly. If air can get by, fuel should too.

Is the plug ever wet with fuel when you pull it after trying to start the bike?

You know, of course, if any of us was to come over and try, it would fire straight up, right?
 

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Discussion Starter · #12 ·
Wow!
Carb works on another bike. That's big deal. Eliminates a lot right off the bat.

Valve clearances has been mentioned already, but valve timing might be at issue. Maybe your valve chain jumped a tooth. It's fairly easy to check. I'll leave it up to you to research how rather than step through the process.

Bad fuel? If you haven't tried fresh gas, you can drain, flush and fill with fresh fuel.

BTW, as long as the bike is in neutral, the kickstand switch shouldn't matter.

Kill switch on the bars may be an issue, but since you have spark, I wouldn't think so. But still, I'd check it out or bypass it by unplugging from the harness.

Did you verify fuel fills the bowl on the carb by turning the drain screw and verifying fuel flows out the bowl? I ask this because I accidentally put the fuel line on the wrong nipple on the carb. Try putting a hose on the fuel nipple and blowing on it to verify fuel is able to get past the float valve assembly. If air can get by, fuel should too.

Is the plug ever wet with fuel when you pull it after trying to start the bike?

You know, of course, if any of us was to come over and try, it would fire straight up, right?
Yep the fact the carb works on a totally different bike is amazing. I was relieved that my effort paid off.

I'll check out the timing, maybe that's the whole trouble of not firing at the right moment. I'll check out other threads on the process but thanks.

New Fuel and opened the drain valve on the carb to allow fuel into it multiple times to be sure the bowl has fuel, it also doesn't pour out so i know the float is working also when i had the carb apart i threw it in a pool of water to be sure it floats. float and spicket does their job.

Spark plug does get a coating of gas, even floods when i mess with the fuel/air mixture valve so gas does get delivered to the cylinder.

ah alright, was wondering about the kickstand sensor. thanks


i opened it up to see if i had any issues with the kill switch but nothing came of it. no issues there.

If it started if someone came here I'd be the happiest guy there, it would probably do the same thing if i took it to a motorcycle shop
 

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Have you tried another plug? I have had a plug that looked good, sparked when I looked at it (ground to the motor) but the insulator had a small crack that would not let it fire correctly. Took me forever to figure out the issue. I think you have, just trying to think of something from your exhaustive list that you might not have tried?
 

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The advice given thus far seems to cover most possibilities. So, I will as my 2 cents only as a summary:

When a bike won’t start and yet the motor will turn over (starter will crank), my typical approach is —

1. Does it kick over “normal”? The first 10 of my 13 bikes had kick starts and it was easy to feel the compression. Without that feature, pull the plugs and put a finger over the plug hole while cranking. If you’ve had the bike a while, the amount of pressure should feel normal. If you have a compression tester, all the better. If rings are not excessively worn, no hole burned in piston and valves operated normal, then move on to the next step.

2. Were plugs wet, when pulled, after trying to start? If not, check for fuel flow...if, then check if -
a. petcock screen not clogged?
b. fuel tank cap venting?
c. petcock flowing?
d. fuel in bowl? (open drain screw is quick way to check)
e. if a-d are OK, then remove carb bowl and check float valve not restricted with debris
f. float level correct?
g. If unsure, does starter fluid get it going? If so, then it is a fuel/fuel mixture issue. Otherwise, then move on to the next step.

3. With plugs out, plugs in high voltage boots, plug prongs grounded (typically to cylinder/head cooling fins), kick the motor or operate the starter. Check for strong bright blue spark. If none, or weak, then check -
a. voltage to coil primary (should be same as battery voltage)
b. measure coil resistance
c. check high voltage plug wires (both ends)
d. check spark plug condition
e. check coil primary connection to CDI (orange wire)
f. If EVERYTHING checks good, but still no spark, then it may be the CDI or CDI magneto

Black font is for any motorcycle
Blue font is late model TW specific.
Gray is N/A for TW
 
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After re-reading this thread a couple times, suggest that you focus on valves not fully closing (AGman), intake seal leaking (pred) and fresh gas (Ski Pro 3) suggestions.
It could also be flooded.
In 2003, I dropped my XLH883 Sportster on a fire road in SoCal.
By the time I got it up, it seriously flooded and did not respond to the starter cranking it.
I had come up a long steep grade, so I coasted until it picked up speed, let out the clutch in second as I bounced on the seat (for traction).
It turned over for several seconds before it fired.
 

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Given that it sounds like it’s on the HT side – you have three (maybe four) possibilities remaining.

Timing – although the timing on the TW is static (non-adjustable), there is a remote possibility the chain position has either jumped, or has been set up wrongly

Duff CDI – this is rare, but not unknown (and notoriously hard to check). Do a forum search on “checking the cdi with a timing light”, though you may first need the engine to actually run

Magneto failure – not as crazy as it sounds, one of the pick-up magnets may be out of whack (sender )

The last one is the ignition coil itself – not the end of the world in terms of accessibility and cost – but check (all) the connections first

So – unless you’re into some major surgery and other $$$ outlay – you either need to start swapping parts from another TW, or throw it at a dealer for diagnosis (any dealer who knows his stuff should be able to give you an answer within an hour)

I just find it strange that it backfires occasionally – this implies that spark and fuel are present

Even if both intake boots where cracked, it should at least try to run .....
 

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Given that it sounds like it’s on the HT side – you have three (maybe four) possibilities remaining.

Timing – although the timing on the TW is static (non-adjustable), there is a remote possibility the chain position has either jumped, or has been set up wrongly

Duff CDI – this is rare, but not unknown (and notoriously hard to check). Do a forum search on “checking the cdi with a timing light”, though you may first need the engine to actually run

Magneto failure – not as crazy as it sounds, one of the pick-up magnets may be out of whack (sender )

The last one is the ignition coil itself – not the end of the world in terms of accessibility and cost – but check (all) the connections first

So – unless you’re into some major surgery and other $$$ outlay – you either need to start swapping parts from another TW, or throw it at a dealer for diagnosis (any dealer who knows his stuff should be able to give you an answer within an hour)

I just find it strange that it backfires occasionally – this implies that spark and fuel are present

Even if both intake boots where cracked, it should at least try to run .....
Thats the really hard part, because it backfires sometimes, that is where valves might make sense. maybe they adjusted and just tightened them to zero tolerance(prior owner)?
 
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