Valve clearance check (timing of) in the real world.

[2and3cylinders]

8 hours ago, dazzler24 said:

Thanks @piotrek.  Yes, from everything I've read about this AIS mod - and you've confirmed it - is that it only really serves two things if you have a non-CAT pipe. 1. If you're getting lots of popping etc on decel then it might be worthwhile to cut that extra air being injected into the pipe and 2. Shave a few lbs off your bikes weight.

I assume (never a good thing) that the ECU flash that can turn off AIS, if it was requested, is only controlling the solenoid in the AIS system and nothing else.  If the ECU is flashed as AIS off then that never actuates the AIS solenoid which permanently shuts off the air anyway and thereby effectively doing what block off plates would do.

Please correct me if I'm wrong.

I assume (again) that a flash that disables AIS does not also modify how the Air Fuel Ratio (AFR) is measured via the O2 sensor as part of that flash?

That was the only reason why I questioned whether a reflash was required.

Yes a flash can turn off the AIS function but with it shut down air can still be drawn into the exhaust track, hence the need for block off covers.  I of course go the extra mile and flip over the AIS check valve reed stops and HTV silicone seal the reeds themselves to absolutely preclude leakage.  Doing so means that block off covers are redundant. Now some have just sealed the hoses with a marble and unplugged the connector to the selenoid; something of course madatory if the parts are removed.  Access and effort is eased with the AIS gone, which is also said to reduce exhaust system temperature that in itself is not a performance gain, it can promote component longevity.

IMO the primary purpose of a flash is to optimize ignition timing and carburation, turn off the fuel cut function under closed throttle decel which greatly reduces snatchiness when the throttle is reopenned, while also turning off the O2 sensor and closed loop adjustments, remove the top speed limiter, lower the fan on operation temp, and likely at least one other feature I'm forgetting.

Nuf said.

[bwringer]

The first reply had all the info needed!

Another data point:

I bought my bike with 21,883 miles in February 2021 and did the valve check while I was bored and waiting for the winter glaciers to recede.

I'm glad I did -- I ended up swapping all 12 shims. For some of the intakes I was able to re-use some of the factory shims. Also, some of the factory shims were oddball in-between sizes, which proved handy for getting things just so.

All the exhaust clearances were way out of spec, and two of the intakes were at the very bottom of spec.

Whenever I'm dealing with valve shims, my aim is to get the clearances at or very close to the upper end of the range for maximum longevity.

Coolant, plugs, sync, and new air filter, and it's set for a good long while. As seems to be the case with nearly every modern bike, valve clearances don't move much after the first one or two adjustments, so I'll plan on the next check at around 40,000 - 45,000 miles, probably sometime this coming winter.

Also FWIW, the low-rent factory chain was completely, utterly, beyond shagged. The PO sure timed things perfectly as far as pushing maintenance on to the next guy... 

 

Edited March 11, 2022 by bwringer

[PhotoAl]

Good points on the valve check.  I'll probably paint marks and zip tie.  Checked my 2004 FZ6 at 24,000 miles and it was in specs.  Checked my 2012 CBR600RR at recommended interval 16,000 I think and it was out of spec.  Pulling the cams was a major hassle and getting everything back together was interesting but got it done - LOL without zip ties or paint marks!  Fascinating thing to me was the timing marks were not exact or to say it differently with everything back together they did not line up exactly.  I expect with Japanese precision and manufacturing they would but not so - took to internet sleuthing to figure it out.  By off I mean much less than a tooth but probably 1 or 2 degrees.  Best part was the bike ran perfectly afterwards.

It is not as easy as most jobs but if you are patient, good with your hands, careful and do your homework before it is not an impossible job.  I've seen some pretty shabby work come out of some bike shops even dealerships.  Get a good shop that has a great reputation in the bike community - preferably the sport bike community.  If they work on sport bikes, Ducatis, Triumphs, Aprillias and have happy customers they should be good - and will probably have a longish wait time.

[2and3cylinders]

3 hours ago, bwringer said:

The first reply had all the info needed!

Another data point:

I bought my bike with 21,883 miles in February 2021 and did the valve check while I was bored and waiting for the winter glaciers to recede.

I'm glad I did -- I ended up swapping all 12 shims. For some of the intakes I was able to re-use some of the factory shims. Also, some of the factory shims were oddball in-between sizes, which proved handy for getting things just so.

All the exhaust clearances were way out of spec, and two of the intakes were at the very bottom of spec.

Whenever I'm dealing with valve shims, my aim is to get the clearances at or very close to the upper end of the range for maximum longevity.

Coolant, plugs, sync, and new air filter, and it's set for a good long while. As seems to be the case with nearly every modern bike, valve clearances don't move much after the first one or two adjustments, so I'll plan on the next check at around 40,000 - 45,000 miles, probably sometime this coming winter.

Also FWIW, the low-rent factory chain was completely, utterly, beyond shagged. The PO sure timed things perfectly as far as pushing maintenance on to the next guy... 

 

 As I stated, I had 2 tight exhaust valves after 16.5k and adjusted a 3rd as well to closer to the loosest spec; I also adjusted a couple of intake valves to bring them closer to Max spec.

 What I'm saying is I wouldn't stretch lash checks for much more than 20000 miles and preferably less.

[peteinpa]

The big variable is the chain. Everything else is precise.  With mileage the chain gets longer and the marks start to wander. It also retards your cam timing. Shifts the power to more low end, less high end. A good thing in my book.

When I had my V65 Sabre I read articles on this, removed my cams (4 of them) slotted my cam sprockets, set them up with a degree wheel at 104 degree lobe centers and noticed....NOTHING. So it's subtle.

There's been a few here and at FZ09 forum that got a tooth off.

With paint it won't happen.

[dazzler24]

7 hours ago, 2and3cylinders said:

For just verifying clearance, yes those steps generally are OK except for turning over CCW with the rear wheel.  That's too imprecise and means moving back and forth inefficiently from upfront where all the action is.  And using a screwdriver is a no-no. Steel inside aluminum vanities can lead to heartache.

OK, understood.

For the shim replacement, indexing by just marking chain, cam sprockets and drive cog is insufficient IMO.  Physically preventing skipping a tooth with zip ties around the chain and sprockets IMO is mandatory.  I also remove the right timing cover and chain tension slider I order to provide enough chain slack to enable setting the cams aside stick zip tied to the chain and sprockets enough to remove the cam follower gifts and shims.

Good advice.

And bare in mind that when reinstalling the cams without adequate chain slack, valve spring pressure on the cam lobe can make them difficult to align with the marks.  Also, there can be enough slack in the chain between the cams to allow being off a tooth with the index points.

A good point to note that I wasn't aware of.

And when removing the cams at 125° BTDC the lobes are not symmetrically opposing each other as they are at TDC; hence the spring pressure on the cam lobes.  There is a special tool that is a narrow flat plate with two short perpendicular pins projecting out near one end spaced to engage holes in the cam sprockets to use as a lever to turn and hold the cam in alignment with its index holes and the cam cap index marks.  90° needle nose pliers will work too.  With the CCT slider removed the added slack obviates the need for this tool.

I have seen the tool you refer to in the service manual.  I do have 90 deg needle nose pliers but may not be required based on your method.  Thanks.

And Skyping or Zooming was only to face to face discuss the foregoing while sipping your choice of beverage while, and also if you desire, burning tobacco, cannibas and / or incense, not to observe and coach in real time you actually doing the deed.  Heavens no!

Ha! I gave the cannabis up decades ago and have recently cut back on alcohol in an attempt to lose few kilos and focus a bit more on my health (after listening to a few stories from members in this very forum! yes - you know who you are 😉).  Boring eh!

But it's not all bad - I do still partake in in a weekly Meth session!  Just had some this morning actually.  Methotrexate that is, not the other one. 😏  Although I believe that a Cannabis extract (CBD oil) may be able to replace the Meth in the treatment of my inflamation ailment - so may be back on that yet!

I would not have either the patience or self control, and not being able to point or smack your hand away is a major detraction. And I'm up at odd hours as I don't sleep much or through the night.  Having a video coffee clutch could be a fun way for the girls to talk amongst ourselves.

You sound like you have the same temperament as me when it comes to patience. Ha!  I've assisted remotely with IT issues and usually find myself with a bleeding forehead after bashing it against the wall in frustration.

"...and not being able to point..."  This is where the AR glasses mentioned earlier come into their own.

That's if we can understand each others spoken English...

I've been known to speak several languages, dialects and in tounges and even shorthand after too much imbibing so that could be a way to bridge any communication issues if required. 😂  Probably not recommended for doing the job at hand though.

All BS aside though, thanks for taking the time to respond with these tips.  It's not something I'll be doing immediately as there a few other life distrations coming up that make this a (slightly) lower priority but look forward to leaning on the wise ones for assistance and guidance.

Cheers and thanks.

 

Please expand the quote for comments.

[dazzler24]

7 hours ago, 2and3cylinders said:

Yes a flash can turn off the AIS function but with it shut down air can still be drawn into the exhaust track, hence the need for block off covers.  I of course go the extra mile and flip over the AIS check valve reed stops and HTV silicone seal the reeds themselves to absolutely preclude leakage.  Doing so means that block off covers are redundant. Now some have just sealed the hoses with a marble and unplugged the connector to the selenoid; something of course madatory if the parts are removed.  Access and effort is eased with the AIS gone, which is also said to reduce exhaust system temperature that in itself is not a performance gain, it can promote component longevity.

IMO the primary purpose of a flash is to optimize ignition timing and carburation, turn off the fuel cut function under closed throttle decel which greatly reduces snatchiness when the throttle is reopenned, while also turning off the O2 sensor and closed loop adjustments, remove the top speed limiter, lower the fan on operation temp, and likely at least one other feature I'm forgetting.

Nuf said.

My current flash consists of: -

·         Start-up set to - STD

·         AIS – ON (Cat fitted)

·         AFR – STD PIPE

·         FAN – 96°

·         Top Speed Limiter – REMOVED

·         Ignition corrected

·         Injector Cut Off - REMOVED

[dazzler24]

6 hours ago, bwringer said:

Whenever I'm dealing with valve shims, my aim is to get the clearances at or very close to the upper end of the range for maximum longevity.

Coolant, plugs, sync, and new air filter, and it's set for a good long while. As seems to be the case with nearly every modern bike, valve clearances don't move much after the first one or two adjustments, so I'll plan on the next check at around 40,000 - 45,000 miles, probably sometime this coming winter.

Setting clearances towards the top end makes good sense to me.  Thanks.

[skipperT]

20 hours ago, 2and3cylinders said:

Oh, and 18k is longer than many manufacturers.  Honda often calls for 16k on lower stressed engines.  The KTM 890 is at 18,300, BMW S1000SX at 6,000! and Triumph Street Triple 765 at 12,000

 

The 790/890’s will be worn out by the time the valve clearances get checked. 

-Skip

[skipperT]

14 minutes ago, dazzler24 said:

Setting clearances towards the top end makes good sense to me.  Thanks.

I wouldn’t sweat the Intake lash, but the exhausts should definitely go to the loosest they can be…

-Skip

[skipperT]

15 hours ago, dazzler24 said:

And is this advice right here that Pete has provided all you really need to do to ensure your timing is guaranteed to be all good when closing up?  And I ask genuinely as it makes sense to me on the surface of the statement.

But as mentioned, it's a job that you don't want to get wrong by taking any short cuts.  Having said that, if it's a method that works and is foolproof (me being the potential fool) then I'm all for it.

I know about lining up the 125deg BTDC marking and the punch marks on the top of the cams etc to reset the timing but if this method mentioned is all you REALLY need then I'm all for doing it that way!

Any potential pitfalls that you can see @skipperT?

I would only paint when you know the cams are coming out for adjustment, otherwise your marks will never line back up unless you rotate the engine backwards (not advisable in this engine)…

the important thing to understand is that you utilize a set of factory marks for inspection, and a different set of marks for cam removal and install. I do mark the relationship between cam and chain before I zip tie and loosen them. 

there's no need to remove the RH pickup coil cover IMHO as 2and3 suggests, as once the tensioner is out you have enough clearance to rotate one cam toward the other and remove the tappets and shims. I do one at a time this way. 

when setting everything back, ensure the chain is TIGHT between the crank and the exhaust cam. That is where many folks get off a tooth. The other spot is that the intake cam has a tendency to rotate and skip the chain due to the position of the lobes when re—assembling. 

If you run into trouble just post, lots of help and experience here to help get you sorted out. 
My $0.02,

-Skip

[dazzler24]

3 minutes ago, skipperT said:

I would only paint when you know the cams are coming out for adjustment, otherwise your marks will never line back up unless you rotate the engine backwards (not advisable in this engine)…

the important thing to understand is that you utilize a set of factory marks for inspection, and a different set of marks for cam removal and install. I do mark the relationship between cam and chain before I zip tie and loosen them. 

I'm assuming you are referring to the TDC and 125 deg BTC marks?

there's no need to remove the RH pickup coil cover IMHO as 2and3 suggests, as once the tensioner is out you have enough clearance to rotate one cam toward the other and remove the tappets and shims. I do one at a time this way. 

OK. - more than one way to skin the cat it seems.

when setting everything back, ensure the chain is TIGHT between the crank and the exhaust cam. That is where many folks get off a tooth. The other spot is that the intake cam has a tendency to rotate and skip the chain due to the position of the lobes when re—assembling. 

I think I read advice from you elsewhere where you also say to make sure to temporarily reinstall the cover to ensure that tension is maintained on the chain between the cams.

If you run into trouble just post, lots of help and experience here to help get you sorted out. 
My $0.02,

Thanks for your input.  Always welcomed.

-Skip

 

[piotrek]

21 hours ago, dazzler24 said:

If the ECU is flashed as AIS off then that never actuates the AIS solenoid which permanently shuts off the air anyway and thereby effectively doing what block off plates would do.

The flash actually energizes the AIS coil to 'hold' the valve closed. I bench tested mine.

It could leak over time as already mentioned.

Edited March 12, 2022 by piotrek

[dazzler24]

47 minutes ago, piotrek said:

The flash actually energizes the AIS coil to 'hold' the valve closed. I bench tested mine.

It could leak over time as already mentioned.

Ah OK - the other way around to how I thought it operated.  Thanks for going the extra yard to find out.

I'm thinking I might do the blockoff plates anyway - just for the convenience of future access if nothing else.

[dazzler24]

OK experts, here's my measured valve lash figures at 20K kms (12.5K miles)

All are in spec with two of the exhaust at the bottom limit.

Do I leave as is or go in and change the exhausts with those being the known problem child?

Leave the intakes?  They look pretty good I would have thought.

TIA