Intake Valve Carbon Build Up

[rydfly]

Hi folks,

Last weekend I performed the 16k maintenance, which included valve clearance inspection. Upon removal of the throttle body assembly, I was surprised to see the amount of carbon build-up that was present on all of the intake valves. (should've taken a picture to illustrate... sorry!)

As an engineer for an OEM automaker and ASE Engine Repair Specialist, I've seen my share of gummed-up valves before and I wouldn't say mine were at a level to have a noticeable impact to performance (yet), but it's definitely there. Curiously, the injectors looked spotlessly clean. The spark plugs looked normal grayish color.

I'm curious for those of you that have seen your own INT valves, have you noticed anything similar?

I'm going to run an occasional bottle of injector cleaner through it for the next 16k miles. It'll be some time before I can judge the effects, though.

I run premium gasoline about 95% of the time, occasionally going to mid-grade once in a while during the colder months and/or on long trips where I'm not looking for MAX performance or HP.

[Volfy]

I run Techron through all my vehicles regularly. Seafoam treatment is even better, but the application is a bit more involved.

It is generally more of a problem for you folks up North, where the ECU tend to enrich the mixture on cold starts. And the atomized fuel spray is more likely on condense on cold intake track. I remember when I lived up North, if I got lazy with the Techron, my car's idle RPM would hunt on cold starts. What happened was the accumulated carbon would absorb some of the intake fuel mixture and caused the engine to run lean briefly. The lamda (O2) sensor picked this up and would try to enrich the mixture to compensate. The carbon would load up and not absorb any more, causing the mixture to go rich, which in turn would cause the ECU to lean the other way.

I don't notice that as much after I moved to warmer climes. These days with Direct Injection, it's also less of a problem.

[telegraphroad]

+1 to the excellent advice above.

When you say "premium" fuel do you mean higher octane or from a more expensive branded supplier? In my experience excessive intake valve deposits are more likely when regularly using cheaper unbranded supermarket fuels which typically save production costs by omitting the additives in more expensive fuels. At least that is the case in the UK where I come from.

[rydfly]

By "premium", I'm mostly talking about the octane rating. I don't go out of my way to find any particular branded fuel source, though most of the time it ends up coming from the same 1 or 2 suppliers since I pass the same stations every day and most of my mileage is from daily commute.

I've always suspected the fuel mapping on these bikes (or at least the earliest 2010 models) wasn't very well suited to colder climates as mine always hunts for an idle for several seconds on start-up when temperatures drop into the 40F range or lower. I did about 1000 miles in SW Texas over the winter with temperatures down into the 20's and saw the worst fuel economy I'd ever experienced with this bike.

-->Volfy, I appreciate your insight and largely agree that's what's likely going on. One note on your comment regarding direct injection... in some cases, carbon deposits can actually be worse on gasoline DI engines. Engine oil weeps down the valve guides (as it does on any engine) and burns or congeals to the stem and head of the intake valve. Since there's no fuel spray directly on the valve to wash it off, it will continue to accumulate. I've seen this first hand many times.

[Tamworth]

I noticed the same build-up during my valve inspection. An article about it (by someone who seemed to have a clue) said it was caused by fuels not having enough additives to combat this, cheating on additives to increase profit. His recommendation was STP Complete Fuel System Cleaner a few times a year, that it was the best for dissolving these deposits. I've been using it but haven't inspected the valves since.

Also the higher oct. gas (91 +) is most likely to have more additives to reduce deposits. But not always.

It is not from crankcase venting back through the air-box, this will not cause intake valve deposits.

[Volfy]

Discussion on octane, methanol, and gasoline in general gets to be more religion than fact. Some people are convinced one way and there is no changing their opinion, so I try not to get too deep into them.

The only thing I'd add relevant to this thread is to use top Tier Gas and to pick high traffic gas stations, where you know the stock is kept fresh. The only assumption I make on higher octane/AKI is that it has higher octane/AKI. It's the same as watching a car with the turn signal ON. The only thing I'm absolutely sure is that car's turn signal light works! So... I pay more for higher AKI when the conditions and the engine calls for it. And for no other purpose.

As for cleaning my engines, I'd rather pay money on something I know works. I have had cars that were RPM-hunting and rough-running on cold starts get cured with one big bottle of Techron concentrate. I'm sure there are other good products - and methods - but I choose to stick with what I know works.

rydfly, DI cures a lot of ills, but it does introduce a few challenges too. Carbon build-up is still possible, but it's more on piston crown instead of intake plenum and valves. That tends to raise dynamic CR, and the ills that go with that.

[swimmer]

There was a thread about carbon deposits on valves on the other VFR site, mostly told from a german guy. Seemed like possible causes were operating the engine to low an RPM or, excessive oil level causing extra oil to be sucked up the crankcase vent into airbox. I have been more cautious about over filling my oil since reading that but I still often ride a low RPM as that seems normal to me.

Like others, I use Techron concentrate regularly. I split a big botttle up over the last 3 or so tank fills before every oil change (4k miles). When I do my air filter change in a few months I'll take a look down into the intake.

[zedXmick]

Since I live up in the freezing hell of the north 6 months of the year, I put seafoam in the tank for every winter storage season, it will be interesting to peek at the valves and see if this has helped. I also run 91 premium (no ethanol) when ever I can find it.

[c5ip]

I've seen the same thing. I use Lucas cleaner (approximately every 3,000 miles) and it seems to work. I've done three valve inspections and the first was the worst given that I started using Lucas after that.

[Switchblade]

I've seen the same thing. I use Lucas cleaner (approximately every 3,000 miles) and it seems to work. I've done three valve inspections and the first was the worst given that I started using Lucas after that.

Good to know.

[Berliner]

For your Information: This ins not a single failure! I experienced it twice. My first 1200f Engine said goodbeye after only 24000 KM, indicaded Cole in all in-Vents. My 2nd VFR (Model 2014) has trouble after only 6000KM -Same Diagnose. Honda did'nt even conduct an inspection After receiving my taken photos but wrote in their neglegtion of my requested warrenty: this trouble is caused due to extremly slow rpm of the engine. Honda-technical Dept. Called me up to anvice me to use Motul vent-cleaner and not to run the engine under 5.000 rpm. Can you imagine that? What a helpful advice! LOL

I tried the cleaner 3 times without success. See the taken picture after usage of the cleaner and after 1300 KM. The in-vents did run less than 7000 KM and are 12 month old.

The photo of the damaged VFR1200 Engine is not mine, but from another 2013-VFR1200.

One of the indpendent german magazine which did not fear the consequence of loosing AD's of the marketing people http://www.motorradundreisen.de published the engine-problem in June 2015. and ask for a combined activity and Inspektion of the in-vents. Honda does does know more, but continue not to communicate this issue!!!

This is a view behind the vents, or lets say an "Infected" VFR1200-engine:

Thank You HONDA!

[hvfrdave]

For your Information: This ins not a single failure! I experienced it twice. My first 1200f Engine said goodbeye after only 24000 KM, indicaded Cole in all in-Vents. My 2nd VFR (Model 2014) has trouble after only 6000KM -Same Diagnose. Honda did'nt even conduct an inspection After receiving my taken photos but wrote in their neglegtion of my requested warrenty: this trouble is caused due to extremly slow rpm of the engine. Honda-technical Dept. Called me up to anvice me to use Motul vent-cleaner and not to run the engine under 5.000 rpm. Can you imagine that? What a helpful advice! LOL

I tried the cleaner 3 times without success. See the taken picture after usage of the cleaner and after 1300 KM. The in-vents did run less than 7000 KM and are 12 month old.

The photo of the damaged VFR1200 Engine is not mine, but from another 2013-VFR1200.

One of the indpendent german magazine which did not fear the consequence of loosing AD's of the marketing people http://www.motorradundreisen.de published the engine-problem in June 2015. and ask for a combined activity and Inspektion of the in-vents. Honda does does know more, but continue not to communicate this issue!!!

This is a view behind the vents, or lets say an "Infected" VFR1200-engine:

Thank You HONDA!

That looks like oil getting past the O rings to me.

[swimmer]

It would be great to see that magazine article in its entirety.

[andy]

Although I always use Tier 1 gas, I usually shift at 5,000. I'm worried, especially since I can't read German. Should I add menehune juice?

[BlueTraveler]

I bought a leftover 2013 three months ago and already have 6,500 miles on it (you can ride year 'round in AZ, but most of the interesting roads are a long way from Phoenix). I'll definitely add Techron treatment to my routine maintenance.

I'm wondering how a PCV figures into this discussion. My bike is completely stock except for a Power Commander V, which I bought to get rid of the low-speed, low-RPM leanness which made the bike difficult to handle at parking lot speeds. It works as advertised. However, installation required disconnecting the stock O2 sensors and plugging in the Dynojet O2 optimizers. Does anyone have an idea of how the PCV might figure into this issue?

[swimmer]

For your Information: This ins not a single failure! I experienced it twice. My first 1200f Engine said goodbeye after only 24000 KM, indicaded Cole in all in-Vents. My 2nd VFR (Model 2014) has trouble after only 6000KM -Same Diagnose. Honda did'nt even conduct an inspection After receiving my taken photos but wrote in their neglegtion of my requested warrenty: this trouble is caused due to extremly slow rpm of the engine. Honda-technical Dept. Called me up to anvice me to use Motul vent-cleaner and not to run the engine under 5.000 rpm. Can you imagine that? What a helpful advice! LOL

I tried the cleaner 3 times without success. See the taken picture after usage of the cleaner and after 1300 KM. The in-vents did run less than 7000 KM and are 12 month old.

The photo of the damaged VFR1200 Engine is not mine, but from another 2013-VFR1200.

One of the indpendent german magazine which did not fear the consequence of loosing AD's of the marketing people http://www.motorradundreisen.de published the engine-problem in June 2015. Thank You HONDA!

Berliner, I tried to download the article but wasn't allowed. I was willing to pay for it.. Can you post the results or provide a summary of what magazine found after their test?

[Berliner]

There should be no issue to download the magazine or order it directly - they ship to all countries.

The Headline: Is the Honda-V4 1200F Engine hazardous?

- This is not a single failure / case

- Honda changed the shanks - but doe not comunicate (communication is a lack)

- Description of the Blowby

- Recall action for VFR1200 - what happened.

- 12 reported damaged engines picked up by the investiation; one fatal casualty reported from Austria on a crosstourer

- Inspection of valves (from above to inspect the carbon deposit) is not part of any Honda-garage

- Watch out for your valves and blue smoke coming out of the exhaust pipe

[luvtoleanit]

I bought a leftover 2013 three months ago and already have 6,500 miles on it (you can ride year 'round in AZ, but most of the interesting roads are a long way from Phoenix). I'll definitely add Techron treatment to my routine maintenance.

I'm wondering how a PCV figures into this discussion. My bike is completely stock except for a Power Commander V, which I bought to get rid of the low-speed, low-RPM leanness which made the bike difficult to handle at parking lot speeds. It works as advertised. However, installation required disconnecting the stock O2 sensors and plugging in the Dynojet O2 optimizers. Does anyone have an idea of how the PCV might figure into this issue?

Did you have it mapped? Or are you running some generic map?

OP, have you made any changes to your intake or exhaust? OEM air filter? Slip-on?

[Volfy]

There should be no issue to download the magazine or order it directly - they ship to all countries.

The Headline: Is the Honda-V4 1200F Engine hazardous?

- This is not a single failure / case

- Honda changed the shanks - but doe not comunicate (communication is a lack)

- Description of the Blowby

- Recall action for VFR1200 - what happened.

- 12 reported damaged engines picked up by the investiation; one fatal casualty reported from Austria on a crosstourer

- Inspection of valves (from above to inspect the carbon deposit) is not part of any Honda-garage

- Watch out for your valves and blue smoke coming out of the exhaust pipe

Thanks for sharing it. I'm guessing I have to pay for the download?

Anyway, interesting... this is different from the earlier discussion in this thread, which was carbon deposit from fuel spray, not oil seepage. I would think if oil is getting past the seals enough to cause problem this bad, there will be indication of oil burning - blue smoke or oil usage. Mine doesn't show either, but I'm gonna keep a closer eye on this from now on.

[crakerjac]

... but I still often ride a low RPM as that seems normal to me.

What is considered a 'Low RPM'? When I learned to drive a stick, I was taught to short shift and lug the engine.... A lot of that carries over to riding a bike. I typically ride in the 3.5k range and drop sub 3k if I'm stuck in traffic.

[BlueTraveler]

I bought a leftover 2013 three months ago and already have 6,500 miles on it (you can ride year 'round in AZ, but most of the interesting roads are a long way from Phoenix). I'll definitely add Techron treatment to my routine maintenance.

I'm wondering how a PCV figures into this discussion. My bike is completely stock except for a Power Commander V, which I bought to get rid of the low-speed, low-RPM leanness which made the bike difficult to handle at parking lot speeds. It works as advertised. However, installation required disconnecting the stock O2 sensors and plugging in the Dynojet O2 optimizers. Does anyone have an idea of how the PCV might figure into this issue?

Did you have it mapped? Or are you running some generic map?

OP, have you made any changes to your intake or exhaust? OEM air filter? Slip-on?

I'm running the stock exhaust, stock air filter, and I didn't mess with the exhaust flapper valve. I'm using the "Stock exhaust Stock air filter" map from Dynojet. This is not the same as a zero map. It makes the fuel mixture richer at all RPM's between idle and 3,000. Above 3,000 it leaves well enough alone. The bike runs great.

Here's a link to the available maps: http://www.powercommander.com/powercommander/powercommander_maps_installs_product_buy_options.aspx?mdlyrid=16-020&make=19&model=218&make-n=Honda&model-n=VFR1200&year=2013&mk=19&mdl=218&yr=2013

Thanks!

[Rider14]

If it is only happening to a few people, and it happened to the same owner twice, is it coincidence? Or is it something about that owner's use of the bike (e.g., the gas he is using)?

Very interesting, if anyone gets that article in English, I'd love to read it,

- Dan

EDIT: Google translate (still want to see article...):

Is the Honda V4 of VFR1200 a ticking time bomb that ultimately for big problems - can ensure - through to the mortal danger? After M & R learned of charred valves and burned pistons, we wanted to get to the base. We started a 1,000-kilometer test drive (see also the report Resin Thuringian Forest in issue 05/15) and the result was so devastating that we simply have to report about it!

Vulnerability Honda V4?

If anyone finds an English translation of the article, please post. Consider my interest piqued.

[AllWeather]

And to think I nearly bought one of these bikes

Sooo glad that I went with an old 6th Gen for peanuts and put the rest of the money onto the mortgage

[zedXmick]

700 mile test drive with devastating results? I covered 700 miles total in my last 2 rides with out devastating results...

[EhViffer]

We did a 9000 plus km 3 week ride 3 summers in a row on a 2010 and 2012 and simply have to report no devastating results.