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Discussion Starter #1
Hello all,

Bike is a 2012 F4 1000 (Brazilian assembly). I’m located in São Paulo, Brazil. Full background on the bike at the end of the post.

Was on a track day last Saturday and on the straight, still accelerating at 200km/h (probably close to rev limit at 3rd gear or shifting to 4th) heard a knock on engine and loose power. For what I remember pulled clutch and when released heard loud rattle.

Coasted to stop. Tried to start bike once and heard something like if one cylinder was open.

Back home, bike on stand, rotating wheel by hand while 6th gear engaged, hear metal click between each compression.

Disassembled air box and found those 2 pieces of metal inside air box.



Ruler is in Centimeters.

Also, looking through throttle bodies, I can see 2 more of those pieces on top of cylinder 4 intake valves.



And comparing what I see on other cylinders, it looks like the end tip of valve guides for cylinder 4 are also missing. Was not able to take a clear picture.

So, what are your thoughts and recommendation on this? I’m probably disassembling head to look further. Thinking of both valves and guides.

I do not have any intention on selling the bike so would want to have the best approach here. But of corse do not want to spend more money than what is really necessary.

Bike background:
As mentioned, Brazilian assembly 2012 F4 (it is same as regular 2010 F4). Bike was purchased new at the end of 2012 and is now with a bit more than 28.000 km on the clock.

Regular maintenance by dealer on first 2 years (1000, 6000 and 12000km services). Did oil and oil filter changes every 3.000km or less. Motul 7100 10w60.

After that did all maintenance by myself being most relevant on this case oil and filter changes every 3.000km or less (particularly when done trackdays), coolant every year.

Never really done any service on valves, timing chain or tensor.

Engine never overheated and never had any failure. Did had some intermittent strange behavior at low rpm and idle, but found out latter a problem with cylinder 1 coil, and it was solved.

Last 12 months bike haven’t seen the streets and did 9 track days (my guess would be something like 2.000km of track usage last year). And some track days before that. Other than this regular road usage.

So thank you in advance and really looking forward for all input to have the bike back up and running.


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Does look like broken pieces of valve guide.
You have serviced the bike at the recommended interval and good quality oil.
Time to remove the rocker cover and cylinder head to investigate further.
Have the valve clearances been checked since you have owned the bike?
 

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Discussion Starter #3
No. Never checked valve clearance. Never really opened the cover


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Valve clearances should be checked every 12000kms.
Your motor may have just had a mechanical failure,it does happen.
 

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Yep, now it seems stupid of me, but never thought it would be a big problem with low mileage...

Should have done, especially with track abuse I was putting lately...

Well, will arrange some space to start working on it and keep you all updates.

Never did this before so will have some question for you guys here.


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You have damaged valves and broken valve guides (the metal bits you found)..... You will need a new head at the very least. With luck your cylinder will be OK, but that one piston will likely need replacement.

Time for a top-end overhaul. Crank and rods should be OK, unless you find major piston damage.
 

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Discussion Starter #7
By new heads you mean the whole thing or just an overhaul?


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Considering the difficulty in replacing valve guides in the radially displaced head, a new head (or good used) would likely be your best bet. But you may be able to refurbish your head.....how good is your machine shop?

Of course, that will depend on the extent of the damage.
 

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Do not even know any machine shop, but would start looking for one after removing the head.

A new head will probably cost more than a new bike (given exchange rates and importation taxes) and if this ends being the only option will likely part out the bike for selling...


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Discussion Starter #10
Do you guys know of other brands with radial valves? Because I could search for a shop with experience on this.


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Do you guys know of other brands with radial valves? Because I could search for a shop with experience on this.
Yes...some Ferraris. A really competent shop with good equipment could probably replace the guides....the key is that they are at a slight angle to the plane of the head. It is not a lot, but it is there and must be accounted for.

Let us know what you find when you pull the valve cover and then the head. Good luck.
 

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Discussion Starter #12
Sure! Will probably take some time to dedicate to this, but will update everyone. I found a shop that says they have experience with Ferrari.


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Ebay has used engines for 2000-2500 euro. You will spend atleast that opening up your motor and replacing parts.

What sort of taxes would you face if you bought complete engine from Europe or US?
 

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Taxes are usually 60% of item plus shipping costs.

Not sure if would be allowed to bring a complete engine, will have to search.

3000 euros, plus shipping, plus taxes converted to Brazilian reais is close to the market value for the bike.

For now I’m trying to be optimist on finding a shop that will do the job.



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?

allanl;
Lets try and minimize your effort and expenses......
Remove the head, be careful of the head, gasket, post pictures of #4 cylinder and piston top of #4
Turn the head upside down and put solvent in each cylinder.....does #4 leak solvent faster?
No, your valves are good, you need guides Yes, you need valves and guides
After seeing the pictures, we will be able to see if the the head can just be welded and refinished

The problem is the piston.....if the damage is on the edges, it's probably pinched the piston ring
which means a new piston and rings.....at least the top ring

The valves and guides come from Del West here in So Cal and aren't very expensive
The piston and rings come from Startwin in Europe

Awaiting the pictures
 

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Discussion Starter #16
Great! Will take some weeks to have it done, but will do.

Thanks


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Hey guys, hope everyone is well.

It’s been a long time, but finally moving on with this.

I’m now ready to remove the frame so I can get to the engine. Seen on the manual that a extractor is needed to remove the bushings from the frame ( special tool No. 8000B4415).

Is there any workaround on this?
 

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Other brands commonly using radial valves include Honda thumpers such as the ubiquitous XL and XR models sporting the RFVC badge and if you want to go back a bit in the 30s Rudge had a 350 with a radial valve head as well. Radial valves can be found on small aero engines a fair amount too where volumetric efficiency dictates their application.
 

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I’m now ready to remove the frame so I can get to the engine. Seen on the manual that a extractor is needed to remove the bushings from the frame ( special tool No. 8000B4415).
Appears to just be a threaded rod that screws into the bushing and used to pull it out. Have you removed the spindle and had a look yet? Just get a long bolt with proper diameter and thread pitch.
 

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Appears to just be a threaded rod that screws into the bushing and used to pull it out. Have you removed the spindle and had a look yet? Just get a long bolt with proper diameter and thread pitch.
No it’s not threaded.

I managed to remove them and will write here for future reference:

The inside diameter is just right for a M6 rubber wellnut to fit very tight. Then I bolted a long M6 bolt to it so it would create internal pressure. Used what is in the following picture to do that:


Then I gently hammered one long screwdriver from the other side and it came loose easily (I had oiled it before and let the oil sit for some time.

So now I’m ready to remove the upper part of the engine. Will keep you posted hopefully on the next days



I inserted the bushings and bolt again so I could secure it on a bursig stand:




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