Something All FJR Owners Should Know

[user 213]

Question - what brand and octane level of gasoline due you burn in your FJR?

Taking a break from the garage.

Never used "bargain" gas, mostly Chevron since I use a Chevron credit card when possible for the bike. Grade - Virtually always regular 87, because that's what the owner's manual recommends, and because I've not had any knock with that grade, so see no reason to use higher octane. And trust me, I do know what knock/pre-ignition sounds like! Supposed to be Techron in all grades, fwiw. :mellow:

edit @MGM - I'd like very much to know what your compression readings are now. Any chance you could do it, or know someone that could help you check them? Some tool rental places, and auto parts stores, rent the compression test equipment. I don't think your motor is worn out, or anyone else's. Just saying what I believe Yamaha thinks our motor life is, judging from my conversations with customer service over my issue.

@Bluesman - You can never go home, eh? I left in '85. Sad that it's over developed now.

@gr8eyes - You're still here?? Glad you are. The compression gauge doesn't have to be expensive for general purposes where you are more interested in cylinder to cylinder variations. Think of it as a comparative tool. With my case, the manual offers a 198-228 psi spec for the FJR, so I'm interested in my absolute values to compare to the spec, and to the dealer's readings.

 

[user 213]

Got hung up on doing the compression test. I don't have the correct adapter for the tiny 10mm spark plugs the FJR uses. I'll have to try and score one of those tomorrow.

Interesting things so far:

The Dealer told me my Irridium plugs were "pretty bad" and needed to be replaced. I told them no, because I can do that myself. Pulling the plugs tonight they all look even in color, (normal light tan), with no deposits or other unusual visual issues. Gap is a tad on the wide side at 0.032". Spec is 0.028-0.031", so we're not talking huge here. Plugs have 18,800 miles on them. I left the last set of Irridiums in for 50k with no signs of significant wear. :huh:

I can see some minor carbon on the piston tops, but again, not anything you wouldn't expect to see, (and I've seen a lot of piston tops, etc.)

Now for some shop manual observations. The manual has a very specific method laid out for doing a compression test. They don't even bother to unplug the injectors, (which I do), and just ground the plug wire not on a plug when you're doing the test, doing one at a time, cranking until the reading stabilizes on the gauge. 14.22 psi variation is max. acceptable. Min. compression is 198 psi, as stated before, Std is 228 psi, Max. is 255 psi.

If comprssion pressure is above the maximum specification, check the cylinder head, valve surfaces and piston crown for carbon deposits. Carbon deposits - Eliminate.

If the compression pressure is below the minimum specification, squirt a few drops of oil into the cylinder and measure again. To my knowledge this was not done by the dealer. I did ask, they said no.

For compression pressure with oil applied into the cylinder: Refer to the following table.

higher than w/o oil - Piston wear or damage No kidding!

Same as w/o oil - Piston rings, valves, cylinder head gasket or piston possibly defective- repair.

Hmm, odd choice of words... defective. Ahh, they probably meant to say "worn".

 

[Fred W]

The Dealer told me my Irridium plugs were "pretty bad" and needed to be replaced. I told them no, because I can do that myself. Pulling the plugs tonight they all look even in color, (normal light tan), with no deposits or other unusual visual issues. Gap is a tad on the wide side at 0.032". Spec is 0.028-0.031", so we're not talking huge here. Plugs have 18,800 miles on them. I left the last set of Irridiums in for 50k with no signs of significant wear.

And the dealer swings, and misses... Strike 2.

For compression pressure with oil applied into the cylinder: Refer to the following table.
higher than w/o oil - Piston wear or damage No kidding!

Same as w/o oil - Piston rings, valves, cylinder head gasket or piston possibly defective- repair.

Hmm, odd choice of words... defective. Ahh, they probably meant to say "worn".

I've gotta take issue with this table. These Yamaha tech writer guys are on crack.

Damaged piston? As in a hole in it or what? Other than holding the rings properly and being a solid, I don't really see how the piston being worn or damaged will result in higher pressure w/ oil. If the top is coked up the compression will be too high with and without oil and the symptom would be pinging (detonation).

I also disagree with the second statement. If the rings are worn the compression pressure will increase with the addition of oil. That's the whole point of doing it, to differentiate between leaking rings and leaking valves. Those are the two biggies anyway.

By the way, this is nothing at all unique to Yamaha, or motorcycles. Compression testing is basically the same on any 4 stroke engine. Only the specs would vary.

 

[Zorlac]

"These Yamaha tech writer guys are on crack."

Fred,

Do they pass the pipe to the torque spec guys when they're done?

After reading all this, I'm thinking, ignorance is bliss.

 

[gr8eyes]

Hi OCfjr, yes I hang around, though I tend to keep quiet if I don't have anything worth saying. LOL I do spend some time over at the OWNERS forum too.

Sorry to hear about all your FJR travails. I'm keeping positive that its not a huge problem.

Glenn

 

[charismaticmegafauna]

Same as w/o oil - Piston rings, valves, cylinder head gasket or piston possibly defective- repair.Hmm, odd choice of words... defective. Ahh, they probably meant to say "worn".

Damaged piston? As in a hole in it or what? Other than holding the rings properly and being a solid, I don't really see how the piston being worn or damaged will result in higher pressure w/ oil.

Piston skirts can crack (or, even break-off -- especially in cases where they've become too loose in their bores). Piston skirts can also deform -- lose their shape (it's really not that un-common).

Poor piston shape = poor piston/cylinder fit = poor compression (and, usually, some engine noise too).

 

[user 213]

Update: Bought a new compression tester since I needed the 10 mm adapter. Slightly nicer unit, but not professional grade. Cost $47, fwiw if anyone is thinking of getting one.

To review, the dealer said my compression values were:

#1 - 155

#2 - 157

#3 - 165

#4 - 152

--------------------------------

My tests:

Dry test, cold engine:

#1 - 165

#2 - 165

#3 - 175

#4 - 160

My numbers seem slightly higher than the dealers. Possibly due to the gauge.

--------------------------------

Wet test, cold engine:

#1 - 180

#2 - 175

#3 - 185

#4 - 170

All up some, but not dramatically, suggesting that there is some ring wear, which is expected, but not a huge amount.

-------------------------------

Dry test, hot engine:

#1 - 169

#2 - 164

#3 - 160

#4 - 155

Oddly, this is the only test where the #3 cylinder isn't higher than the others. I do note that the variation between cylinders isn't large enough to concern me. Pushing the limit of the shop manual's range though.

-------------------------------

After doing the tests, all of which were done with a fresh Yamaha air filter in place, wot, injectors unplugged and the same test gauge, I attached some vac lines to the TB sync ports and sucked in some top end cleaner, then shut the bike down. I don't have the option tonight to leave it overnight, but will go back out later and suck the rest through the engine, then take the bike for a ride, toss some ring free in the gas tank and fill it up, then do some freeway runs with high rpm and wot. Heading out on a ride at 0400.

The idle is still uneven. (It wasn't when I dropped the bike off, though the shop says they noticed it.) The cam chain tensioner is still noisy, more than ever in fact. Bike rides mostly ok, but doesn't seem to want to let the rpms drop when you close the throttle. Almost makes me wonder about air leaks. Both the erratic idle and the not wanting to drop on throttle close would support that. Pull the clutch in and the rpms drop. I did double check that the throttle cable had slack. No issue there.

Erratic idle could be many things, from simple bad spark plugs, to mis-adjusted valves. (there's a scary thought)

Right now, what I'm seeing leads me to believe that more of the issue is valve related. Either carbon build up, or??

Also a correction - My bike does seem to be using some oil. It's right between the hi and low on the sight glass. Normally when full, it's closer to the top mark. This is after 6500 miles though. Never gone that far before between changes. Normally right at 5k miles. Not using a lot of oil, but using some.

More after the weekend and I'll put on 1k or so, then test the compression again. Still waiting on the cam chain tensioner to show up and get installed.

 

[BobbyBlue]

Hi OC, Glad to hear you're collecting some good data and passing it along too! I thought I might mention something that affected my idle and was cured by some insight somewhere in the giant forum collective brain. My bike has to live outside, albeit covered but outside. My problem was corrosion city in several of the main connectors on the harness, some up front but the worst was under the tank and they were part of the coil or higher voltage/current systems. Lots of perty green ! I cleaned these up and dressed em up proper like and it made a hell of a difference in idle/smoothness and cleared up a couple other little gremlins as well. I realize this may be of no import and I agree with your possible air leak theory in light of the evidence but I thought it'd be easy enough to check since you've obviously been spending some time there anyway B) . Good luck and thanks for sharing, makes for a better world for sure!

Blessings,

Bobby

 

[J-DADDY]

OC

Thanks so much for your ongoing comprehensive posting on your findings concerning your bike.

I've a feeling you're gonna find the culprit and there'll be a simple solution. Sure hope so for ya!

Gotta admit I'm rivited! Please continue to let us know what you find.

JC

 

[Checkswrecks]

Hi OC, Glad to hear you're collecting some good data and passing it along too! I thought I might mention something that affected my idle and was cured by some insight somewhere in the giant forum collective brain. My bike has to live outside, albeit covered but outside. My problem was corrosion city in several of the main connectors on the harness, some up front but the worst was under the tank and they were part of the coil or higher voltage/current systems. Lots of perty green ! I cleaned these up and dressed em up proper like and it made a hell of a difference in idle/smoothness and cleared up a couple other little gremlins as well. I realize this may be of no import and I agree with your possible air leak theory in light of the evidence but I thought it'd be easy enough to check since you've obviously been spending some time there anyway B) . Good luck and thanks for sharing, makes for a better world for sure!Blessings,

Bobby

As you mentioned, there's not enough spread to worry about. As long as you're not out for top speed or something, you'll probably not notice the slight reduciton in hp.

With respect to your idle, Bobby had some words of wisdom for you. If you're in Oregon with a 2004, I'm willing to bet on your having corrosion in the ECU connector under the tank. Search on "ECU Connector Contamination" and you'll find a thread with great photos of the connector and how to get to it.

Bob

 

[v65]

The cam chain tensioner is still noisy, more than ever in fact. ... Still waiting on the cam chain tensioner to show up and get installed.

If it was me I would wait for that until I did anything else. Fix the known problem, and then start chasing the compression issue: the tensioner could fix your problem.

 

[charismaticmegafauna]

The FJR spec for compression is 198-228 psi. Mine was 155/157/165/152. Leak down was 18%/16%/15%/25%. Acceptable leak down is 3-5%. Give or take. Over 10% is usually indicative of a problem. Leakage was occurring past the rings and the valves, both in significant amounts.
The conclusion? "Your motor is worn out".

Facts is facts....

Another course of action would be to build an FJR compression data-base. Those with the ability can post their engine's compression specs (and other pertinent data -- year, miles, etc). Just maybe? Mama Yama's compression specs are 'calculated' and don't really exist in the 'real world'?

IOW, if many respondents report good running FJRs all with 155 ~165 psi compression numbers -- well, that may be what's really out in the field.

OTOH, maybe most do have 200+ psi?

With a broad enough sampling we may have a better handle on this. :huh:

 

[dougc]

Update: Bought a new compression tester since I needed the 10 mm adapter. Slightly nicer unit, but not professional grade. Cost $47, fwiw if anyone is thinking of getting one.
More after the weekend and I'll put on 1k or so, then test the compression again. Still waiting on the cam chain tensioner to show up and get installed.

Eric,

After you get back, if you want to cart your tester around, we could check my 80K+ mile '05 as an added data point.

Similar break-in, irridiums with close to 20K miles, "chapman blend" for oil, and Chevron regular/87 for gas. No problems experienced and its not been ridden since returning from Maine after Labor Day.

dougc

leaving the driveway this weekend on dual-sport only

 

[rogdeb]

Still following this thread with interest Eric. Don't claim to even come close to understanding the "tech" stuff, but looks like you're making positive progress. Good on ya!

 

[PA1195]

OCfjr, I've read the thread with interest, only from a returning owner standpoint. Just some helpful thoughts. I did check the compression while doing a TBS on my former two FJR's up to about 5K miles each to monitor ring break-in. The warm values were well above 200 (about 220-230), and within 10% on all cyls. Motoman-type break-in as always.

I'd try more of this stuff - https://www.yamaha-motor.com/sport/apparel/...323/detail.aspx - which you may have already done via another product for all the reasons stated in previous posts.

I'd also do a TB test/synch with the pilot screws initially set to the same values, like 1 turn out. Gross differences may indicate induction leaks that you mentioned (providing the throttle plates haven't been previously adjusted to balance at cruise), or differential cylinder sealing due to ring or valve leakage. The vacuum values may follow cylinder compression. As I recall, my vacuum values were around 250mm at 1k rpms on a Morgan unit, and lower of course at higher rpms. The TBS at idle and cruise would of course do little to affect cylinder seal, but may help balance the engine to each cylinders output some for smoother running, should normal wear have occurred, and you note increased vibration.

I also assume the head gasket is tight, and there's no combustion chamber gunk in the coolant reservoir, or unexpected loss of coolant over time.

If there's some ring blow-by (which was noted via the leak down test), your new oil will darken quickly in the sight gauge. Running 20W-50 should help minimize any leakage.

Gary in Fairbanks

 

[Fjroamer]

Hey Eric!

not up to your mileage yet but your post has been intriguing. Just shared my experience in 40,000 mile service thread and concluded:

"I think a lesser machine, with my lack of regular maintainence, would not be looking so good at this point..... but then I ponder OCFJR's dilemma..... What (if anything) did we do different??? I haven't the answer......."

...could it have been the yellow jacket??? :blink:

Roamer

 

[jocko87]

The FJR spec for compression is 198-228 psi. Mine was 155/157/165/152. Leak down was 18%/16%/15%/25%. Acceptable leak down is 3-5%. Give or take. Over 10% is usually indicative of a problem. Leakage was occurring past the rings and the valves, both in significant amounts.
The conclusion? "Your motor is worn out".

Facts is facts....

Another course of action would be to build an FJR compression data-base. Those with the ability can post their engine's compression specs (and other pertinent data -- year, miles, etc). Just maybe? Mama Yama's compression specs are 'calculated' and don't really exist in the 'real world'?

IOW, if many respondents report good running FJRs all with 155 ~165 psi compression numbers -- well, that may be what's really out in the field.

OTOH, maybe most do have 200+ psi?

With a broad enough sampling we may have a better handle on this. :huh:

As one of the few lucky folks with an spare, low mile, Gen 1 engine laying around I'll try to do a compression check before I drop it out of the frame just for point of reference. My first 05 was a dealers bike for the first 2,000 miles so we have to assume the break-in was per Yamaha specs right? It turned 7,000 the day it went down and ran like a ***** ape. Give me a couple weeks and I'll have some solid numbers for the baseline.

Kurt

 

[user 213]

Hey Eric!...could it have been the yellow jacket??? :blink:

Roamer

You sir, are a bad man.

:lol: :lol:

 

[user 213]

Thanks for the positive input guys, and the continued tips/suggestions. I remain open minded to all ideas. The corrosion aspect for the idle is certainly worth checking out. Skooterg mentioned that to me this weekend as well. I'll read the info on the forum and check mine out and report back.

Bike ran ok while under way this weekend, but idle still falls on it's butt and If I adjust it high enough when warm to idle normal, it ends up way high later. Also a new aspect of the idle issue, no cold high idle now. Fired up cold it wants to idle at 700, IOW, not at all. Before it went to 2k like normal and the funky idle didn't show up until it hit one bar and started to drop down. If anything, the warm idle is more consistently low now. Not sure if that's good or bad. With the idle backed off on the low end, the bike does respond more normally when closing the throttle now.

I had some opportunity to flog the bike a bit while in NV. Did a few wot 1/2/3/4 to 9500 runs and some normal double downshift passes. Now it's wanting to bog when I give it more than a little throttle at a time unless the rpms are way up there like 6k+. At normal 4k or so cruising, if I whack the throttle, it will decel until I back the throttle off, then slowly bring it up. Made for some awkward passes on the way home.

I'm going to take a look at the oil and maybe change it again tomorrow, then pull the plugs and do another compression test. The Yamalube cleaner appears to be very similar to what I used, just a spray form instead of liquid. Easier to safely use w/o ingesting too much liquid into the engine if you're not familiar with the process. I've BTDT before, so wasn't worried about using liquid. (note: Liquid doesn't compress, as we all remember from physics class, so too much in the combustion chamber would be bad)

 

[El Toro]

I've read and re-read the initial post, and I am a bit confused. The bike has 88,000 miles, not 60,000 miles. And although the compression is lower than spec, all of the cylinders seem close to each other (that's good), and the bike's not burning oil in any noticeable way (that's also good). I would get the cam chain tensioner replaced as planned (probably already done by now), and I would just keep riding. A bike with this many miles on it isn't going to be worth much to trade or sell anyway. If its not burning oil, and if there is enough power to ride safely, and maybe even enough power to continue to have some thrills, don't let the data collection get in the way of enjoying your bike... you may end up well over 100,000 miles before you know it.

You know it is unlikely that any manufacturer will quote a specific target life. It used to be that 100,000 miles was about all you could expect out of any US built automotive engine. My Dad always traded his cars at 30,000 miles because that was still during the "constant hazard rate" failure performance and before the "wear out failures" started to kick in.

20 years ago I was friends with the chief engineer of the engine division of one of the big 3 US auto companies. He told me that they were just starting to figure out that if you wanted something to last without significant failures for 100,000 miles, you had to design it with an expected life of 200,000. 10 years later, my GMC Sierra gave me over 200,000 trouble free engine miles. Wish I could have said the same for the final drive/rear end.