Slow Cold Start?

[PoorUB]

2018 RT, about 20,000 miles. This year it started acting up on a cold start, cold like over night or longer. Any way, i can hit the on button, wait a second or two for the tach and speedo needles to sweep and park, then hit the starter button and it just cranks, no fire. I will crank it for 2-3 seconds, drop the button and try a second time and it pops right off.

On the first try is I keep cranking it will not start, but stop cranking for a second and it always takes right off on the second attempt. Hot zero issues, pops right off.

Any guesses why?

 

[LFarling]

My experience with this says the Cam Position sensor is off. It is on the left side on the end of the cam shaft.

Problem is you must do a full cam check to set the cam position sensor correctly.

Your a bit far away or I would offer to do it for you. I rode around and did about 35 of them for a period of time just to see how bad the cam timing was off. Most were off. I have seen bikes that needed a second push to start, stop it immediately after a cam alignment and cam sensor set.

 

[Omega Man]

Kinda interesting that the new engines have no idea where the are in the run sequence until the sensors “sync” up.
Good post LF.
OM

 

[LFarling]

Kinda interesting that the new engines have no idea where the are in the run sequence until the sensors “sync” up.
Good post LF.
OM

It is something I discovered while I rode around and did these for fun.

It is a go, no go with the timing jig on the cam shaft so that is why I say most were out. Some were off but very close to the jig going on, others not even close.

So you set your cams and then while on the left hand side while it is set up for the cam check you adjust the cam position sensor.

It is something I feel needs done since I and others have seen so many of them off while doing cam checks on 1200's.

I have not done any 1250's but would imagine cam alignment and cam position sensor would be very important on a double cam lobe. After all that is what is telling the bike to move the the other cam lobe when operating.

 

[lee]

On the first try is I keep cranking it will not start, but stop cranking for a second and it always takes right off on the second attempt. Hot zero issues, pops right off.

Any guesses why?

Some of the 1200 wethead bikes have the double tap starting problem. Always does a quick start on the 2nd try.
My wife's bike did it more than mine. She learned to let up if it didn't immediately start on the the first try.

 

[Geekmaster]

This may simply be superstition or voodoo, or there may be some scientific reason. I read in one forum where someone suggested a recalibration of the throttle position sensor. Anyway, they said to follow these steps:

1. Turn on the key. Don't start the engine.
Wait for the "boot up sequence" to finish.
2. Slowly open the twist grip to full throttle and slowly return to idle, three times.


3. Turn off key and wait one minute for everything to shut down.

4. Start the engine normally.

I was having this problem and tried the steps, and it seemed to work for me. Keep in mind that it had only happened 4-5 times before I found this "solution".

It may or may not work, but it is easy to try.

Not sure if you have to stand on one foot with your head tilted or not ...

 

[jono]

This may simply be superstition or voodoo, or there may be some scientific reason. I read in one forum where someone suggested a recalibration of the throttle position sensor. Anyway, they said to follow these steps:

1. Turn on the key. Don't start the engine.
Wait for the "boot up sequence" to finish.
2. Slowly open the twist grip to full throttle and slowly return to idle, three times.


3. Turn off key and wait one minute for everything to shut down.

4. Start the engine normally.

I was having this problem and tried the steps, and it seemed to work for me. Keep in mind that it had only happened 4-5 times before I found this "solution".

It may or may not work, but it is easy to try.

Not sure if you have to stand on one foot with your head tilted or not ...

Pretty sure this works best if you turn your head away from the bike and gaze off to the horizon, so the bike thinks you are ignoring it.

 

[windsailor97]

I will preface my reply with the comment there is no replacement proper mechanical adjustment etc....

that said, my experience with double tap, hard starting was resolved by running Chevron Techron through a tank. Having to hit the start button twice went away. I previously tried the recalibration of the throttle position sensor and no change.

I probably need a cam position sensor adjustment from what I have read but in terms of hard starting, the snake oil short cut solved my problem for the time being.