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Discussion Starter · #1 ·
I needed a modern bike since I am tired of working on my 30 year motorcycles. Then i figured out i wanted a modern bike with a classic look.... So, i a bought a Triumph Scrambler, 馃檶

As the topic reveals... the bike dont start.

First of, i changed the battery, topped of the tank, checked for spark, headlight dims when start button is engaged, clutch switch working, removed the tank to check connections, fuel pump starts up, all the fuses checked, side stand switch checked....

The status on the bike, the starter turns the motor but no sign of starting

Atm I'm out of ideas, anyone got a sugestion?

Thanks
Thor
 

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Is the battery fully charged ? What about your connections from the battery to the starter, and the ground ? Are your connections dirty or loose ?
 

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Discussion Starter · #3 ·
Is the battery fully charged ? What about your connections from the battery to the starter, and the ground ? Are your connections dirty or loose ?
Battery fully charged. Will check the connections 馃憤 but i believe they are good since the starter motor turns the engine 馃?
 

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2004 Daytona 955i, 2018 Indian Roadmaster, 1980 CB650C in resto
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Do you smell gas while it's cranking? Does it have compression?
 

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First of, i changed the battery, topped of the tank, checked for spark, headlight dims when start button is engaged, clutch switch working, removed the tank to check connections, fuel pump starts up, all the fuses checked, side stand switch checked....
A few ideas to check out.

I assume there was a spark when you checked? After a while cranking without start, are the plugs wet?

If wet - check out the crank position sensor, followed by coils and HT leads. CPS should read about 200 ohms when cold. Scrams have single fire coils, not sure of the readings on those.
If dry - no fuel - check the secondary fuel filter (in the fuel line T connector between the throttle bodies) and that injectors are not blocked. The main fuel filter is in the tank. The pump pressurizes the fuel to 46psi.. do you have fuel pressure? You can check that visually by pulling off the fuel line, and turning on the ignition, catching the fuel in a jug.

Could be as simple as a vacuum lock in the tank. The tank does not vent through the cap like the old days, it vents through a rollover valve fixed to the front of the airbox, behind the engine. The valve has a ball in it that sits at the bottom, blocking the vent and preventing overspill from getting out. As fuel level in the tank drops, the vacuum lifts the ball and lets air in, also sucking any fuel in the pipe back into the tank. Its worth it to make sure the valve isn't stuck closed and the vent pipe is not blocked or kinked.

You could also check for fuel starvation by spraying easy start into the air intake while cranking, in which case the bike would start momentarily if there is a spark.

When you turn on the ignition, does the speedo go through its startup checks (needle sweep)? If any of the speedo electrical connections are lost, the bike won't run. Canbus models (2011+) have a nasty habit of crimp connections breaking inside the wiring harness, just where it passes the steering head. When this happens, movements in the steering cause intermittent cutouts, erratic speedo/idiot light behaviour or complete blackouts.
 

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Discussion Starter · #6 ·
A few ideas to check out.

I assume there was a spark when you checked? After a while cranking without start, are the plugs wet?
There is spark.

If wet - check out the crank position sensor, followed by coils and HT leads. CPS should read about 200 ohms when cold. Scrams have single fire coils, not sure of the readings on those.
If dry - no fuel - check the secondary fuel filter (in the fuel line T connector between the throttle bodies) and that injectors are not blocked. The main fuel filter is in the tank. The pump pressurizes the fuel to 46psi.. do you have fuel pressure? You can check that visually by pulling off the fuel line, and turning on the ignition, catching the fuel in a jug.
Will look in to the coils. Want to try to replace the spark plugs, maybe it will solve the issue. Didnt know there was a secondary fuel filter, thanks for tip.
Question regarding the crank position sensor. Is there a way to meassure that? Is it a common hall effect sensor?


Could be as simple as a vacuum lock in the tank. The tank does not vent through the cap like the old days, it vents through a rollover valve fixed to the front of the airbox, behind the engine. The valve has a ball in it that sits at the bottom, blocking the vent and preventing overspill from getting out. As fuel level in the tank drops, the vacuum lifts the ball and lets air in, also sucking any fuel in the pipe back into the tank. Its worth it to make sure the valve isn't stuck closed and the vent pipe is not blocked or kinked.
Will check that. thanks

You could also check for fuel starvation by spraying easy start into the air intake while cranking, in which case the bike would start momentarily if there is a spark.
I have tried that. Unfortunately it does not make the bike fire.

When you turn on the ignition, does the speedo go through its startup checks (needle sweep)? If any of the speedo electrical connections are lost, the bike won't run. Canbus models (2011+) have a nasty habit of crimp connections breaking inside the wiring harness, just where it passes the steering head. When this happens, movements in the steering cause intermittent cutouts, erratic speedo/idiot light behaviour or complete blackouts. The startup check is good.
Thanks for response!
 

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Discussion Starter · #8 ·
The "idle" adjuster under the fake carbs... Could that affect the startup if its not correctly adjusted?
 

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Typing your reply into my post makes it very difficult for me to reply to you. Highlight the text in my post that you wish to reply to and a 'Add Quote' button will appear. You can do this as many times as you like. Then at the bottom of the editing window you will see an 'Insert Quotes' button that will automatically put all the quotes into the editor. At that point you can also delete any quotes you don't need.

Will look in to the coils.
Be careful, the coils are an expensive component and have been known to be faulty even though their resistance readings have shown to be fine. If the plugs are sparking and its not a weak spark, then the bike should run on them. I would have a look at the leads/plug caps first and make sure that the leads are making full connection to the coil. Plug caps have a 5k/ohm resistor in them, which can be checked with a multimeter. I would also get a multimeter on the bike wiring and make sure they are getting voltage before looking at replacing them.

Having said that, because your bike does not fire on either cylinder, the problem is most likely to be something which is common to both cylinders. The only component which fits that criteria in the ignition system is the crank position sensor. It would be extremely rare if both coils or plugs went down at the same moment.

Want to try to replace the spark plugs, maybe it will solve the issue.
But earlier you said that there is a spark. How did you test for this - did you have the plugs out and rested against the head?

Question regarding the crank position sensor. Is there a way to meassure that? Is it a common hall effect sensor?
Its a coil, similar to the playback head of a tape recorder and works the same way - a magnet on the alternator rotor induces a voltage pulse in the coil as it passes. The voltage pulse is then sent to the ECU as a signal to fire the plug. It works similar to, but is not a hall effect sensor.

The wiring comes from the alternator cover, the connector is found on top of the airbox and is a bit difficult to access. You can get a cold reading with a multimeter across the (unplugged) connector. It should read somewhere around 200 ohms for a Canbus bike, or 500 ohms for a carbie. Actual readings will vary since coils have a tolerance of about +/- 20%.

The usual check is to get two readings, one cold and one hot. The hot reading is obtained by removing the sensor and sitting it in a jug of boiling water for a couple of minutes. Both hot/cold readings should be roughly the same. But that test is for when the bike is running but begins to have problems when normal engine temperature is reached. However your bike will not even fire so if the CPS is the culprit, it will show up as faulty even when cold.

One thing to consider when doing the hot/cold tests is that the CPS needs to be removed, which means a new alternator gasket. So in terms of cost, it is just as well to simply replace the sensor and eliminate it from the investigation. The sensor is the cheapest component in the ignition system.

I have tried that. Unfortunately it does not make the bike fire.
Then I would say that the problem is electrical.

And you might find this stupid, but its a honest mistake even by the experienced and has happened a few times on here - check the state of the kill switch.
 

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Then I would say that the problem is electrical.
If OP has spark, but starter fluid doesn't get the engine to even sputter like he said, something isn't being tested accurately. I have never had an engine with a good spark, not at least sputter with starter fluid. OP have you checked the gap on the spark plugs, what is their condition (fouled, chalky, etc) and how are you testing for the spark?
 

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If OP has spark, but starter fluid doesn't get the engine to even sputter like he said, something isn't being tested accurately. I have never had an engine with a good spark, not at least sputter with starter fluid. OP have you checked the gap on the spark plugs, what is their condition (fouled, chalky, etc) and how are you testing for the spark?
That is the part that has me confused, the OP says there is a spark, but then goes on to say that it may fix the issue if he replaces the plugs. He also says that the fuses have been checked but if he's doing that visually it is not a reliable method - a fuse can be blown or faulty even if it looks okay.

He has also stated that he can smell fuel when cranking but does not say if the plugs are wet when taken out, or even if he has taken them out.

I have had engines that won't even fire with starter fluid, but that's always been due to no spark. I'm just trying to find out whether the fault is electrical or down to fuel starvation. It has to be one or the other, then it can be narrowed down.
 

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Discussion Starter · #12 ·
Typing your reply into my post makes it very difficult for me to reply to you. Highlight the text in my post that you wish to reply to and a 'Add Quote' button will appear. You can do this as many times as you like. Then at the bottom of the editing window you will see an 'Insert Quotes' button that will automatically put all the quotes into the editor. At that point you can also delete any quotes you don't need.


Be careful, the coils are an expensive component and have been known to be faulty even though their resistance readings have shown to be fine. If the plugs are sparking and its not a weak spark, then the bike should run on them. I would have a look at the leads/plug caps first and make sure that the leads are making full connection to the coil. Plug caps have a 5k/ohm resistor in them, which can be checked with a multimeter. I would also get a multimeter on the bike wiring and make sure they are getting voltage before looking at replacing them.

Having said that, because your bike does not fire on either cylinder, the problem is most likely to be something which is common to both cylinders. The only component which fits that criteria in the ignition system is the crank position sensor. It would be extremely rare if both coils or plugs went down at the same moment.


But earlier you said that there is a spark. How did you test for this - did you have the plugs out and rested against the head?


Its a coil, similar to the playback head of a tape recorder and works the same way - a magnet on the alternator rotor induces a voltage pulse in the coil as it passes. The voltage pulse is then sent to the ECU as a signal to fire the plug. It works similar to, but is not a hall effect sensor.

The wiring comes from the alternator cover, the connector is found on top of the airbox and is a bit difficult to access. You can get a cold reading with a multimeter across the (unplugged) connector. It should read somewhere around 200 ohms for a Canbus bike, or 500 ohms for a carbie. Actual readings will vary since coils have a tolerance of about +/- 20%.

The usual check is to get two readings, one cold and one hot. The hot reading is obtained by removing the sensor and sitting it in a jug of boiling water for a couple of minutes. Both hot/cold readings should be roughly the same. But that test is for when the bike is running but begins to have problems when normal engine temperature is reached. However your bike will not even fire so if the CPS is the culprit, it will show up as faulty even when cold.

One thing to consider when doing the hot/cold tests is that the CPS needs to be removed, which means a new alternator gasket. So in terms of cost, it is just as well to simply replace the sensor and eliminate it from the investigation. The sensor is the cheapest component in the ignition system.


Then I would say that the problem is electrical.

And you might find this stupid, but its a honest mistake even by the experienced and has happened a few times on here - check the state of the kill switch.
Typing your reply into my post makes it very difficult for me to reply to you. Highlight the text in my post that you wish to reply to and a 'Add Quote' button will appear. You can do this as many times as you like. Then at the bottom of the editing window you will see an 'Insert Quotes' button that will automatically put all the quotes into the editor. At that point you can also delete any quotes you don't need.


Be careful, the coils are an expensive component and have been known to be faulty even though their resistance readings have shown to be fine. If the plugs are sparking and its not a weak spark, then the bike should run on them. I would have a look at the leads/plug caps first and make sure that the leads are making full connection to the coil. Plug caps have a 5k/ohm resistor in them, which can be checked with a multimeter. I would also get a multimeter on the bike wiring and make sure they are getting voltage before looking at replacing them.

Having said that, because your bike does not fire on either cylinder, the problem is most likely to be something which is common to both cylinders. The only component which fits that criteria in the ignition system is the crank position sensor. It would be extremely rare if both coils or plugs went down at the same moment.


But earlier you said that there is a spark. How did you test for this - did you have the plugs out and rested against the head?


Its a coil, similar to the playback head of a tape recorder and works the same way - a magnet on the alternator rotor induces a voltage pulse in the coil as it passes. The voltage pulse is then sent to the ECU as a signal to fire the plug. It works similar to, but is not a hall effect sensor.

The wiring comes from the alternator cover, the connector is found on top of the airbox and is a bit difficult to access. You can get a cold reading with a multimeter across the (unplugged) connector. It should read somewhere around 200 ohms for a Canbus bike, or 500 ohms for a carbie. Actual readings will vary since coils have a tolerance of about +/- 20%.

The usual check is to get two readings, one cold and one hot. The hot reading is obtained by removing the sensor and sitting it in a jug of boiling water for a couple of minutes. Both hot/cold readings should be roughly the same. But that test is for when the bike is running but begins to have problems when normal engine temperature is reached. However your bike will not even fire so if the CPS is the culprit, it will show up as faulty even when cold.

One thing to consider when doing the hot/cold tests is that the CPS needs to be removed, which means a new alternator gasket. So in terms of cost, it is just as well to simply replace the sensor and eliminate it from the investigation. The sensor is the cheapest component in the ignition system.


Then I would say that the problem is electrical.

And you might find this stupid, but its a honest mistake even by the experienced and has happened a few times on here - check the state of the kill switch.
Used som spare spark plugs I have and connected it to the spark plug cap. It could probably be spark plugs that are faulty since it doesnt fire with starter fluid. Sorry for not being specific about that point.

Will meassure the pick up coil (y)
 

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Discussion Starter · #13 ·
If OP has spark, but starter fluid doesn't get the engine to even sputter like he said, something isn't being tested accurately. I have never had an engine with a good spark, not at least sputter with starter fluid. OP have you checked the gap on the spark plugs, what is their condition (fouled, chalky, etc) and how are you testing for the spark?
Used som spare spark plugs I have and connected it to the spark plug cap. It could probably be spark plugs that are faulty since it doesnt fire with starter fluid. Sorry for not being specific about that point.
 

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Used som spare spark plugs I have and connected it to the spark plug cap. It could probably be spark plugs that are faulty since it doesnt fire with starter fluid. Sorry for not being specific about that point.
You need to pull the plugs to see what their condition is. Now you know that the coil is producing properly based on a new plug, but the ones installed may be gapped incorrectly or fouled and not producing a spark. I'd start there rather than something more invasive. Until you can get the bike to fire on starter fluid, there is no point in checking beyond the plugs themselves.
 
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