Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => 411 & 450 Himalayan & Scram => Topic started by: pmperez2014 on March 12, 2021, 11:25:33 pm

Title: Engine tune-up or congenital failure
Post by: pmperez2014 on March 12, 2021, 11:25:33 pm: Good evening friends, I want to consult my engine tune-up problem, I can't get a stable idle, there are ups and downs in the RPM and it ends up turning off, after riding for half an hour and with the engine relatively warm stop failing. It is noticeable with less reaction when operating the accelerator, it works like drowning, you hear back-explosions and it wants to stop, you notice a heavy operation, it is difficult to pick up speed, it takes time to reach 100 km / h. I have regulated the TPS voltage at 0.58 V and touched the air screw a bit. I have to do the work because in my city there is no suitable workshop for this setting. I wonder how the ECU is resetting, what sensor or what else may be failing. Should I check the throttle cable adjustment? Is the TPS sensor damaged? or the MAP? I'm really tired and thinking of selling it, because my experience with this bike was not good from day one. I think the problem is in the air and fuel proportions of the mixture (the spark plug is a bit carbonized), but I do not know the procedure to achieve the correct setting. In advance, I greatly appreciate any help that can end this problem.
Title: Re: Engine tune-up or congenital failure
Post by: oldphart on March 12, 2021, 11:40:51 pm: It might help to know:
EFI or carby?
How many kms?

I can't help with your issues but I would suggest you try a new plug, the Bosch that comes from the factory is pretty crap and maybe it's breaking down.
Title: Re: Engine tune-up or congenital failure
Post by: pmperez2014 on March 13, 2021, 11:30:57 am: It is EFI (BS4, year 2020), 3500 km. It has a new spark plug (NGK CR8E, 0.8mm).
According to the service manual, my motorcycle exhibits erratic idling and engine misfiring at low rpm and gives three groups of possible causes:
1.Related to Ignition
2.Related to fuel / induction
3. Related to compression

Which of the three options should I start to look at? Thanks
Title: Re: Engine tune-up or congenital failure
Post by: tooseevee on March 13, 2021, 11:48:02 am: Quote from: oldphart on March 12, 2021, 11:40:51 pm
It might help to know:
EFI or carby?
How many kms?

I can't help with your issues but I would suggest you try a new plug, the Bosch that comes from the factory is pretty crap and maybe it's breaking down.

He says it has 3,500 kms and that he has put in an NGK. I'll bet it's a bad pin or something in one of those hundred electrical connectors these new bikes have.
Title: Re: Engine tune-up or congenital failure
Post by: Richard230 on March 13, 2021, 01:58:20 pm: Quote from: tooseevee on March 13, 2021, 11:48:02 am
He says it has 3,500 kms and that he has put in an NGK. I'll bet it's a bad pin or something in one of those hundred electrical connectors these new bikes have.

That happened to my 2014 Zero electric motorcycle. When it was new one of the battery modules was not being recognized by the bike's computer. The dealer couldn't find the problem so they brought in a factory technician and he discovered that one of the multi-pin connectors had a pin bent when it was jammed together at the factory. He straightened out the pin of the connector, reconnected the wires and the bike ran fine after that.
Title: Re: Engine tune-up or congenital failure
Post by: pmperez2014 on March 14, 2021, 12:15:06 am: Thanks for sharing your experiences, I'm still looking for the cause of the problem.

Today I found out that the air filter box cover does not have the rubber seal on the inner side, can this affect the combustion?
Title: Re: Engine tune-up or congenital failure
Post by: viczena on March 14, 2021, 12:35:37 am: Sounds like false air is coming into the manifold. Check all screws and seals.
Try brake cleaner on the manifold. If the rpm advances you have a leak.
Title: Re: Engine tune-up or congenital failure
Post by: zimmemr on March 14, 2021, 03:30:13 pm: If you had a sensor failure I'd think you'd also have a check engine :MIL light on. Since that isn't the case I'd discount any sensor issues, at least for the time being. A bad airbox leak might cause the problem, as Viczen suggests you may have an intake tract air leak.

You may also have a clogged fuel filter/fuel pump, which is a known problem with the Himalayans and easy enough to check so if resealing your airbox doesn't fix it, that'd be my first stop.

That being said since the problem becomes worse as the engine heats up I'd also take a look at the valves before going too much further. A tight valve will certainly cause the symptoms you describe and will get progressively worse as the engine heats up. A bad coil will also act much the same way as will bad grounds or poor connections. So it's always a good idea to check all the connections in the ignition and power circuits. You may also want to check the coil if possible, most decent motorcycle shops whether they sell RE's or not should have a proper coil testing device. Another thing that will cause your issue is a bad sparkplug cap, I'd replace the stock with and NGK out of hand.

There have also been some issues with failing main power relays. That problem seems to be confined to Interceptors but it's something else that should be checked. Remove the relays, clean the grease from their pins and reinstall or replace them.

I'd also caution you not to jump to any conclusions, a dirty plug indicates something amiss in the combustion process, but that doesn't necessarily mean that the AF ratio is off, it just means the mix isn't burning properly, which could be caused by anything from ignition issues to a clogged air filter to failing fuel pump.

Lastly if all else fails perform a compression check, it's a long shot but your engine may have suffered some mechanical damage.
Title: Re: Engine tune-up or congenital failure
Post by: kiwistopher on March 15, 2021, 09:49:00 am: Thanks, I'll change my plug.
Title: Re: Engine tune-up or congenital failure
Post by: pmperez2014 on March 17, 2021, 12:52:29 am: Thank you zimmemr very much for all the explanation, it helps me a lot.
In fact I'm going to focus on the first cause you mention: the air leak in the airbox.
I tried increasing the air with the golden screw and the bike idle about 2000 rpm or more and no stop, but there I hear a slight blast of air in the area of the throttle body, so I think I have to look for a possible air leak.
I'm going to see that and then comment on what happens. Saludos
Title: Re: Engine tune-up or congenital failure
Post by: Bilgemaster on March 17, 2021, 06:05:53 am: Quote from: viczena on March 14, 2021, 12:35:37 am
Sounds like false air is coming into the manifold. Check all screws and seals.
Try brake cleaner on the manifold. If the rpm advances you have a leak.

Based on the symptoms you described, I believe "viczena" described the likeliest cause: an air leak. Like he suggests, try shooting a little bit of spray brake cleaner, carb cleaner, starter fluid or even WD-40 around the intake manifold. If the rpm increases, you've found the leak.
Title: Re: Engine tune-up or congenital failure
Post by: pmperez2014 on March 17, 2021, 01:09:55 pm: Ok, I'm doing that test today. Thank you
Title: Re: Engine tune-up or congenital failure
Post by: pmperez2014 on March 18, 2021, 11:15:51 pm: The air leak seems to be confirmed.
I hear a hum in the TPS area, when spraying there with body throttle cleaner, the rpm increases for a few seconds and then the engine shuts down. My next step was to check the valve regulation, is it worth doing or do I focus first on fixing the leak?
Title: Re: Engine tune-up or congenital failure
Post by: viczena on March 18, 2021, 11:37:04 pm: Fix the leak.
Title: Re: Engine tune-up or congenital failure
Post by: AzCal Retred on March 20, 2021, 01:41:55 am: " I'm really tired and thinking of selling it, because my experience with this bike was not good from day one. I think the problem is in the air and fuel proportions of the mixture (the spark plug is a bit carbonized), but I do not know the procedure to achieve the correct setting. "

Before you give up and scrap a basically good machine, there is a plan "B" that doesn't involve becoming an EFI tech:

https://accessories.hitchcocksmotorcycles.com/41381?ref_page=HimalayanPART No. 90058

CARBURETTOR CONVERSION KIT (Himalayan) ; £335.00

Carburettor conversion kit for the fuel injected Himalayan models. This kit includes all the components required to convert your Himalayan away from fuel injection to a CV carburettor.
All of the components are bolt on items, and it is a completely reversible modification. Supplied jetted to suit the standard Himalayan model.

H's has a PDF of their install instructions on the part page. Here's an excerpt:
"The carburettor is supplied with a base setting for a standard Himalayan and will require fine tuning. The carburettor comes jetted to suit a standard Himalayan. As a base setting, turn the pilot air screw in fully, and then unscrew by 1 ½ to 2 full turns."
Pretty straightforward, just keep the fuel & air clean and it should work well for you.
Title: Re: Engine tune-up or congenital failure
Post by: viczena on March 20, 2021, 01:47:50 am: If he does not fix the leak in or around the manifold, a carburator will be of no help. Even if you paint it red and blue.
Title: Re: Engine tune-up or congenital failure
Post by: AzCal Retred on March 20, 2021, 03:13:20 am: True enough if it's a gasket or O-ring that can be easily replaced or resealed. If it's a cracked/defective throttle body component, maybe less so. Doesn't sound like there's much local support. Sounds like a chronic problem if it was always present, possibly a factory defect. At least we have determined there's no deuteranomaly or protanomaly going on here.
Title: Re: Engine tune-up or congenital failure
Post by: Bilgemaster on March 20, 2021, 11:52:01 am: Quote from: pmperez2014 on March 18, 2021, 11:15:51 pm
The air leak seems to be confirmed.
I hear a hum in the TPS area, when spraying there with body throttle cleaner, the rpm increases for a few seconds and then the engine shuts down. My next step was to check the valve regulation, is it worth doing or do I focus first on fixing the leak?

(https://media.springernature.com/lw685/springer-static/image/art%3A10.1007%2Fs12685-019-00237-0/MediaObjects/12685_2019_237_Fig17_HTML.jpg)
"One thing at a time!"
Title: Re: Engine tune-up or congenital failure
Post by: Karl Fenn on March 20, 2021, 03:42:54 pm: Judging by his spraying it's almost certainly an air leake, l have had a carb with a hair line crack.
Title: Re: Engine tune-up or congenital failure
Post by: oldphart on March 22, 2021, 10:34:00 am: Quote from: AzCal Retred on March 20, 2021, 01:41:55 am
" I'm really tired and thinking of selling it, because my experience with this bike was not good from day one. I think the problem is in the air and fuel proportions of the mixture (the spark plug is a bit carbonized), but I do not know the procedure to achieve the correct setting. "

Before you give up and scrap a basically good machine, there is a plan "B" that doesn't involve becoming an EFI tech:

https://accessories.hitchcocksmotorcycles.com/41381?ref_page=HimalayanPART No. 90058

CARBURETTOR CONVERSION KIT (Himalayan) ; £335.00

Carburettor conversion kit for the fuel injected Himalayan models. This kit includes all the components required to convert your Himalayan away from fuel injection to a CV carburettor.
All of the components are bolt on items, and it is a completely reversible modification. Supplied jetted to suit the standard Himalayan model.

H's has a PDF of their install instructions on the part page. Here's an excerpt:
"The carburettor is supplied with a base setting for a standard Himalayan and will require fine tuning. The carburettor comes jetted to suit a standard Himalayan. As a base setting, turn the pilot air screw in fully, and then unscrew by 1 ½ to 2 full turns."
Pretty straightforward, just keep the fuel & air clean and it should work well for you.

Stirrer ;D
Title: Re: Engine tune-up or congenital failure
Post by: oldphart on March 22, 2021, 10:36:46 am: I don't know the part you're talking about, but if it's rubber, be aware that the Indian rubber that RE uses can be pretty crappy. I got this from a mate with a Cont GT (the single) and he's had rubber issues.
Title: Re: Engine tune-up or congenital failure
Post by: Karl Fenn on April 04, 2021, 05:57:17 pm: It does sound if the air leak is the main cause not sucking in right mixture, get it air tight then run test it might be ok.
Title: Re: Engine tune-up or congenital failure
Post by: pmperez2014 on April 10, 2021, 08:19:17 pm: Hello gentlemen, thank you for your opinions.
As the bike is still under warranty, I decided to stop reaching for it and take it to the local RE dealer, who I doubt has technical support up to the task. After leaving the bike there for two days, they inform me that they "fixed" the problem: they just increased the RPM by touching the gold air intake screw. Now the behavior of the motorcycle is as follows:
1.Starts with a cold engine and when releasing the accelerator it does not maintain idle and turns off. I was instructed to hold the 2000 rpm on the throttle for two to three minutes to warm up.
2. After those minutes operating the accelerator, when releasing it the motorcycle regulates at 1500 rpm (although irregularly).
3. When driving and testing on the street, it no longer turns off in the corners because it has more revolutions, but then with the engine warm the motorcycle regulates at 2000 rpm. If I turn off the engine and restart it, it stays at 1500 rpm for two minutes and automatically goes back up to 2000 rpm and there it stays. In other words, they did not solve anything, of course they charged me for the "service".

I claimed that abnormal behavior (it was just Friday) and they told me that I will take the bike the following Monday. They say they will continue to "regulate." I think they will continue to play with the golden screw. I still think it is an air leak and maybe a manufacturing defect in the throttle body. The problem was present from the first day 1, I feel cheated and angry because I should not have received the motorcycle in those conditions, all the time they tried to convince me that the operation of the motorcycle was "normal". Will I have to take the bike again as many times as necessary until they admit and recognize the real problem? I do not know what to do. Saludos!!!!
Title: Re: Engine tune-up or congenital failure
Post by: viczena on April 11, 2021, 06:08:00 am: If the airleak is done it could still be an erratic engine temp sensor. The dealer can readout the values and look if they are plausible.

But if you dealer just increased the idle RPM to "cure" the problem, you should look for another dealer.
Title: Re: Engine tune-up or congenital failure
Post by: Ambrosig on December 04, 2021, 09:28:53 pm: Quote from: pmperez2014 on March 12, 2021, 11:25:33 pm
Good evening friends, I want to consult my engine tune-up problem, I can't get a stable idle, there are ups and downs in the RPM and it ends up turning off, after riding for half an hour and with the engine relatively warm stop failing. It is noticeable with less reaction when operating the accelerator, it works like drowning, you hear back-explosions and it wants to stop, you notice a heavy operatio.....
Disconnect negative from Battery about 2 or 3 hours
Title: Re: Engine tune-up or congenital failure
Post by: dlapierre on December 04, 2021, 10:32:52 pm: I had idle issues when my Himalayan was new. The idle was a bit erratic and it stalled from idle often. I did these two things and it made all the difference:
-I called the dealer and asked what the voltage from the ECU should read and I then adjusted it using a voltmeter. It was off just a wee bit. I forget just what it was supposed to be. You should ask the dealer. If they don't know, as them to ask the manufacturer what it should be. That's how they found out for me when I asked.
-I installed a booster plug. Cheap and easy to install.

Those two little fixes fixed all my problems.
Title: Re: Engine tune-up or congenital failure
Post by: longstrokeclassic on December 04, 2021, 11:23:27 pm: I think your TPS value may be a bit on the low side. After a lot of experimentation I came to the conclusion that 0.63v was pretty close to the optimum setting for the Keihin fuel injection system unless you’re deviating from the stock set-up.
Title: Re: Engine tune-up or congenital failure
Post by: dlapierre on December 06, 2021, 01:06:51 am: That sounds about right.