No compression

[oldfast007]

*Disclaimer* Be sure there is nothing wrong with the valve train....

Is there any weird noises coming from the valve area?? if not =, ya I'd try a bump start...I'd also try giving the starter a little love tap while cranking it over, see if you can get it to engage.

Good luck!!

 

[Motogiro]

Someone mentioned a starter selenoid similar to the Bendix type but I believe the system uses a one way type gear assembly.
Check out this link:Ronayers.com Fiche Desktop Motorcycle Yamaha 2006 FZS6VC YZ6 STARTING MOTOR

And also: Ronayers.com Fiche Desktop Motorcycle Yamaha 2006 FZS6VC YZ6 STARTER

From what was described, this could be where the problem is.....Take a look.

 

[skooter65]

Someone mentioned a starter selenoid similar to the Bendix type but I believe the system uses a one way type gear assembly.
Check out this link:Ronayers.com Fiche Desktop Motorcycle Yamaha 2006 FZS6VC YZ6 STARTING MOTOR

And also: Ronayers.com Fiche Desktop Motorcycle Yamaha 2006 FZS6VC YZ6 STARTER

From what was described, this could be where the problem is.....Take a look.

Good call Motogiro! I hadn't even realized that our bikes had a one-way style starter. Here is a decent link for the description; no reason that this couldn't still be the issue:
Sprag clutch

 

[nedburt]

Thanks for the info Motogiro, I believe my starter is ok. The motor is turning over. I'm picking up a compression gauge tomorrow, need to find out if I have compression or not. Any ideas on the best place to find one? I was going to try the auto parts stores first.

 

[Motogiro]

Good call Motogiro! I hadn't even realized that our bikes had a one-way style starter. Here is a decent link for the description; no reason that this couldn't still be the issue:
Sprag clutch

Thanks for that link Skooter! Very enlightening with great 3-D simulation! :rockon: And yes we will still get the clicking sound with a dead battery cuz the starter relay chatters at low voltage.
This could be the culprit. Never heard of one going bad except that BMW example. If she bump starts, it could be that sprag clutch...

 

[Motogiro]

Thanks for the info Motogiro, I believe my starter is ok. The motor is turning over. I'm picking up a compression gauge tomorrow, need to find out if I have compression or not. Any ideas on the best place to find one? I was going to try the auto parts stores first.

I know it's a way down the rabbit hole to the plugs and so you may need something special to get a reading.
Can any of our more experienced members/mechanics chime in on this?

Also: Do you know if you've got spark?

 

[nedburt]

Just pulled all the plugs, they're all pretty black with about 30,000 miles on them. Cylinders 2 and 3 are a bear! I checked cylinder 4 for spark and it was ok, assumed the others are as well. I've never done a compression check before, any advice would be very helpful.
I could be totally wrong here, but does anyone know if there's some sort of automatic compression release that could be stuck?

 

[oldfast007]

If you locate a gauge this may help...

 

[Ridgeback]

Just pulled all the plugs, they're all pretty black with about 30,000 miles on them. Cylinders 2 and 3 are a bear! I checked cylinder 4 for spark and it was ok, assumed the others are as well. I've never done a compression check before, any advice would be very helpful.
I could be totally wrong here, but does anyone know if there's some sort of automatic compression release that could be stuck?

My KTM Duke 2 had a weird way of starting.Key in,starter switch down,auto compression button in,hit the start button and the engine would spin exactly like yours as if it had no compression,then release the auto button while still pressing down on the starter and bingo,it would fire up.

Don't know if the FZ has anything like that,that you don't have to manually engage?

 

[TownsendsFJR1300]

When you checked the timing chain, was it very taught? If not it may have jumped a tooth causing the lower compression. A way to verify this is to remove the valve cover and check the valve timing (intake and exhaust cams and crankshaft) as well as remove the chain cover (to verify the crankshaft is at TDC).

As for a compression tester, you'll need an extension hose to screw down into the spark plug hole. I'd bring a spark plug and make sure you get the correct thread.

As for a automatic compression release, there is none...

***** When was the last time you checked/adjusted the valves?****
If its never been done (it calls for checking at 26,600 miles) the valves can be partially open when their supposed to be closed (not enough clearance as the valves tighten up with time/mileage) and cause the low/no compression/faster cranking. I'd pull the valve cover, find TDC and slip a feeler gauge inbetween the cams and the shims. If there's NO CLEARANCE, they need adjustment.

Good luck

 

[wolfc70]

***** When was the last time you checked/adjusted the valves?****
If its never been done (it calls for checking at 26,600 miles) the valves can be partially open when their supposed to be closed (not enough clearance as the valves tighten up with time/mileage) and cause the low/no compression/faster cranking. I'd pull the valve cover, find TDC and slip a feeler gauge inbetween the cams and the shims. If there's NO CLEARANCE, they need adjustment.

Good luck

This is what I was thinking. A valve might be hanging open just a little bit, enough to reduce compression.

Checking valve clearances might be a good place to start. A leak down test might help also.

 

[nedburt]

The timing chain was taught when I checked it, but I just pulled the bottom cover off.
I had the valves checked at about 25,000, all were in spec. From what I hear, if they're good at the first check, they'll "PROBABLY" never need adjusting. I'm thinking that checking them is the next step, along with a compression test.

 

[TownsendsFJR1300]

You probably already know, but when you check them, make sure the cams are set on ther marks and your at TDC at the crankshaft (double checking to make sure you haven't jumped a tooth at a/the camshafts).

When checked at 25,000 they may have been tight but within spec not requiring adjustment.

Generally, yes, (depending on how hard the bikes run), the FZ will not require adjustments better than most bikes but you do have an additional 25k on the engine, and that's after a long ride. Hope its that simple and no bent valves, etc....

Good luck.

 

[nedburt]

I did a search on here, but does anyone know where I can find a good write up(with pics maybe) on how to do a valve adjustment. I would really like to get a Clymers Manual but I can't seem to find one.

 

[Shamus McFeeley]

There is a link on this site to the service manuals. The cylmer manuals were never very good in my opinion.

Bonemans site has a link to the manuals as well:
Bonemans Site

Checking valve clearances is not that hard, do not be intimidated. You just need time and patience.

 

[wolfc70]

I did a search on here, but does anyone know where I can find a good write up(with pics maybe) on how to do a valve adjustment. I would really like to get a Clymers Manual but I can't seem to find one.

You do not need to do a full adjustment now. Only check the clearances to see if this is part of your problem. All you need is a set of feeler gauges. Just make sure that the cam lobe is pointing up when you check the clearances. All you are trying to do is get an idea of the clearances. You will be able to tell right away if a valve is being held open, no feeler gauge will fit between the bucket and the cam.

If you were going to do an actual shim replacement, then I would follow the proper procedures. This way you can also verify that the cams are moving properly. Remember, we are still in diagnostic mode yet. No need to fix something that may not be broken yet.

 

[TownsendsFJR1300]

You do not need to do a full adjustment now. Only check the clearances to see if this is part of your problem. All you need is a set of feeler gauges. Just make sure that the cam lobe is pointing up when you check the clearances. All you are trying to do is get an idea of the clearances. You will be able to tell right away if a valve is being held open, no feeler gauge will fit between the bucket and the cam.

If you were going to do an actual shim replacement, then I would follow the proper procedures. This way you can also verify that the cams are moving properly. Remember, we are still in diagnostic mode yet. No need to fix something that may not be broken yet.

While in that far, I personally would be checking cam shaft timing (to crankshaft timing), ruling out the chain didn't jump. But yes, there should be some clearance between the valves and cams.

 

[nedburt]

Did a valve check tonite, heres what I found:
Intake valves=good
Exhaust valves= clearance is supposed to be between .23mm-.30mm, mine were all at .15mm
Still don't think that would be enough to cause my symptoms, but I've def. been wrong before.
Thoughts?

 

[TownsendsFJR1300]

Although your clearances are tight(and need adjustment, it should start).

While the valve cover is off, pull the right side cam chain cover and check the cam shaft(s) timing to the crank. In the manual I sent you it'll show you how it should be. It needs to be exact....

If thats on the money, with that cover off, hit the started briefly and make sure everything is turning over (crankshaft,cams) just in case you sheared something. It won't start as the cover ignition module is off.

 

[nedburt]

Checked timing, looks spot on. I guess I'll bring the exhaust valves back into spec, put new sparkplugs in and see what happens.