Cause for concern?

Joined
Feb 19, 2007
Messages
19
Location
Thousand Oaks
Bike
2016 FJR1300ES
STOC #
309
Hi guys,
I did my valve check this weekend on my 04' and while most valves were within spec, I found 2 that were a bit loose so I decided to change out their shims. Both happened to be on the left side and so I only removed the cams on the left. I was a bit surprised to find the following on the intake and exhaust cam bearing surfaces. Pics 1 and 2 are from the intake and exhaust cams bearing surfaces. Pic 3 is from one of the other cam bearing surfaces that looked perfectly normal. Both pics 1 and 2 are from cylinder #3 on the left rear side.

I was quite surprised to see the obvious wear marks, not to mention the obvious 2 divots in the cam surface! I have never dropped these cams and to my knowledge nothing has ever struck them to the point that this kind of mark would have been made, let alone one on each cam!

So, the questions are: Is this an obvious defect in the metal? Will the surface of the cam bearing just get worse and what could I possibly do to even fix it? It appears that these surfaces just ride on the aluminum surface of the head and don't have their own bearing inserts. So is it just going to get worse and cause the cam to get loose and the tolerances to get sloppy?
Anyone else ever notice this kind of wear on cyl #3?????

Coincidently, the two shims I changed just happened to be one exhuast on cyl #3 and one intake on cyl #3! But the other two valves were in spec still!
Bike has about 32,000 miles so far.

Hal #309
 

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wjbertrand

Ventura Highway
Joined
Feb 8, 2005
Messages
4,407
Location
Ventura, CA
Ugly! What do the bearing caps and running surfaces on the head look like? It appears as though a small chip of material came out of the cam bearing surface and scratched things up. I would get some Plastigage and check the clearances.

Another thought, do you use any assembly lube when you put the cams back in?
 

Scooter

This space for rent...
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Oct 12, 2005
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1,779
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Germantown, WI
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2019 BMW R1250RT
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5929
Sure looks like something got it here at one time or another. I'm not sure you could do anything about it now. Even if you had the extended warranty, would Honda cover this as being a defect? Just curious.

With the mileage that you have on the bike this would be the second valve check. Did you perform the first one and if so, I take it you didn't notice anything at that time???
 
OP
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HalR
Joined
Feb 19, 2007
Messages
19
Location
Thousand Oaks
Bike
2016 FJR1300ES
STOC #
309
This is the second valve check. I did the first one. No, at that time I did not notice any issues with the bearing surface. I am usually very careful to make sure everything is clean when reassembling. Even if I had trapped something in there, that would not explain pitting. Nor would it be likely that I would have trapped something under both cams! If something actually got past the oil filter, I would have thought that it would cause a big groove in the surface, not a pit. It almost seems like maybe there is more heat in cyl #3 and that is part of what is causing this, but I don't know.

I thought about using some assembly lube while putting this back together, but reasoned it won't make any difference at this point. That stuff gets dissolved very quickly once the engine is running with hot oil pushing through it. I just don't know what to think at this point. Could have been a plugged oil hole on the cam, but on both cams?

The main concern is what it's going to do over the next 10/20 thousand miles? I don't think it's worn enough to make any problems yet. I would suspect it will just wear quicker than the rest of the bearing surfaces and then I'll need to either have it machined and some kind of bearing caps put in, or I'll need to replace the entire head!... I can hardly wait! :>)
 

RCS

Joined
Jul 3, 2008
Messages
1,401
Location
Stamford, CT
Out of curiosity, how often have you been changing your oil and what type/brand oil filter do you use?

(I know it has nothing to do with this situation but I was going to change my oil replacement frequency from 4,000 to 8,000 per the manual).

If I'm reading the Service Manual correctly on page 4-2. it looks like the Left Rear Cylinder is at the End of the oil flow chain. Maybe, and I am really, really guessing here a contaminant got stuck in the oil stream above the third cylinder, cut off oil for a short time, and then fell onto/into the camshaft to cause those grooves. But, that is really a guess on my part.

As to whether it is a cause for concern, I don't know. I imagine if the surface is rough, it may create more heat in the rough area and possibly wear more quickly as a result. If it were my engine I would flip a coin, really, to decide whether to replace all the worn pieces - at probably $500 - or put the new shims in and check it again in 16,000 miles realizing I may have to replace the worn pieces at that time.

Someone that knows more than me about engine/cam/valve tolerances can probably confirm or refute this: If just the shims are replaced now and that part of the cam wears more quickly the worst that can happen in the next 16,000 is that the valves may not fully open on that cylinder and sieze your engine.

Don't listen to me. I throw this thought out for discussion purposes only.

When I rebuilt my first engine at 17 years old(me) I didn't have the right tools and reused the circlips holding on the piston rod. As I was leading the race the next day I seized my engine. Of course, I learned a lot from that experience about getting the right tools and replacing important parts during maintenance. But, I am no expert.
 
Joined
Nov 11, 2007
Messages
184
Location
Greer, SC
A replacement Cam is $116 on hdlparts.com. For that much money I would just get a replacement instead of worrying about more of the metal coming off the cam and causing internal engine damage.
 
Joined
Dec 8, 2004
Messages
607
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Spring Valley AZ
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Aprilia Atlantic 200
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3925
This is the second valve check. I did the first one. No, at that time I did not notice any issues with the bearing surface. I am usually very careful to make sure everything is clean when reassembling. Even if I had trapped something in there, that would not explain pitting. Nor would it be likely that I would have trapped something under both cams! If something actually got past the oil filter, I would have thought that it would cause a big groove in the surface, not a pit. It almost seems like maybe there is more heat in cyl #3 and that is part of what is causing this, but I don't know.

I thought about using some assembly lube while putting this back together, but reasoned it won't make any difference at this point. That stuff gets dissolved very quickly once the engine is running with hot oil pushing through it. I just don't know what to think at this point. Could have been a plugged oil hole on the cam, but on both cams?

The main concern is what it's going to do over the next 10/20 thousand miles? I don't think it's worn enough to make any problems yet. I would suspect it will just wear quicker than the rest of the bearing surfaces and then I'll need to either have it machined and some kind of bearing caps put in, or I'll need to replace the entire head!... I can hardly wait! :>)
Hal, KLRs do this with alarming regularity if the oil's not checked often, usually MUCH worse. If the worst happens the head can be built up and line bored to accept a new cam and caps. There's info about this on the KLR boards, there's a speed shop in Petaluma that is highly recommended for this procedure. Any GOOD machinist can do this too.

ALSO: http://cgi.ebay.com/ebaymotors/HONDA-ST1300-ST-1300-ENGINE-HEAD-VALVES-JOURNALS-ETC_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el1116QQhashZitem53d44d00bbQQitemZ360044101819QQptZMotorcyclesQ5fPartsQ5fAccessories
 
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HalR
Joined
Feb 19, 2007
Messages
19
Location
Thousand Oaks
Bike
2016 FJR1300ES
STOC #
309
Just a follow up on this old post now that I have 77,000 miles on the bike. Some of you cautioned about continuing to run the bike with the cams in this condition. Everyone seemed to think I should do something about it, like replace the cams at least. Well, I decided to just leave it alone and monitor it over the next few valve checks. During the next 2 checks, first around 47,000 miles I made no adjustments. At 66,500 miles I did adjust the #3 cylinder to loosen it up on both intake and exhaust a bit, but it was still within tolerance, just near the tight end of the tolerance. The condition of the bearing surface was unchanged. Looked pretty close to the original pictures. I'll do another check after WeSTOC during the winter months. I don't expect there to be any change though. Engine runs/idles fine, doesn't overheat and doesn't burn oil. I recently had the opportunity to compare my bike with Jeff Bertrand's during a trip together when we switched bikes for an hour and I can honestly say they ran with about the same power and smoothness.

These bikes are built tough!
Hal
 

ST_Jim

In the Hotel California...
Joined
Dec 8, 2004
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581
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Simi Valley, CA
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2004 ST1300ABS
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Well Hal, that's exactly what I would have done! Button it back up, but keep an eye on it.

It does sound a little like the 'poxy cams on the old VF750's in the early eighties. But my recollection is that was caused by lack of proper oil flow. This looks to be more of a single defect.
 
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