Valve Clearances - to check or not to check

Hi All

Once again I'm here looking for advice:

I've got a Honda Blackbird that's just due for its 16000 miles. The book
says it should have the valve clearances checked (for the first time). My
local independant workshop said they wouldn't bother doing that if there was
nothing to suggest it needed it.
If I give it to the main dealer I'm sure they'd charge me for doing it but
less certain that they would actually do it.
So it seems that I'd have to do them myself but the independant dealer did
start me wondering whether it was really necessary.

What do people do and/or has anyone done the job themselves on a Blackbird
of that mileage? If so were they far out?

Any advice would be much appreciated

Kr1s

 

Do it yourself. You'll have a record of where they're at, when you check
them again at the next major service you can then judge the rate of change
and decide whether to skip/extend the interval between checks.

They say, "nothing to suggest it needed it". I wonder how you'd know if
they were too tight without the engine already suffering from the effects
of leakage. Under spec but not actually leaking there'd be really no way
to tell. Too loose, obviously they'd be noisy, but shim under bucket
style valvetrains don't generally get looser over time.

All that said, you're probably safe to let it go, but I'd do it because I
like to track things like that.

 

The problem with (nearly all) modern engines is that wear and settling
causes value clearances to reduce rather than get bigger.

In the old days you could tell when clearances needed to be checked by the
obvious clatter.
Tight valves don't make themselves known until permanent and expensive
damage has been caused.

There's every chance they are OK but you never know.

Honda wouldn't have included it in the service schedule unless they
considered it important.

I'd get them checked, either by someone you trust or diy with a
knowledgeable friend.

 

Moving into pedant mode, Suzuki tell me to torque up all my exhaust
studs every 4000 miles. They might consider that important, I don't!

 

Leaky headpipes will make a bit of noise. Tight valves will give little
or no warning and are likely to burn, meaning an expensive valve job.

 

Too right, and if my post implied otherwise I apologise.

 

Having experienced (many times) the utter joy asociated with removing
exhaust headers, I do this. I don't just click a torque wrench at
them though - I undo the nut/bolt/stud a bit and then re-tighten.
Apart from this being the only way to get an accurate figure, it means
that the bastard things wikll come out when/if I need them to.

 

Strike them from your list of people you'd trust to do any job properly,
then.

 

Agree. Having owned a divvy 6 with a rotted collector box I am
familiar with the misery of having to needlefile an exhaust stud out.
I have learned my lesson and once every two years remove, copperslip
and replace all the exhaust bolts on both my bikes.When the exhaust
rusts or I need to get the head off I will be a happy chap.

That is not the same as merely torquing them up which IMHO is a waste
of time. If they've stayed put for a few thousand miles they aint
going anywhere - the problem is getting the fuckers out.

None of this is anything to do with Blackbird Valve Clearences and I
now wish I hadn't started the digression.

 

If I give it to the main dealer I'm sure they'd charge me for doing it
but

Well, two things really:

1. When I needed shims for my last bike the main dealer mechanic was
surprised to find his shim box empty. If he was doing the job regularly he
would have known what was in there.

2. They can, without me being any the wiser.

I've started to do it myself but have stumbled at the first hurdle - does
anyone know how to get the fuel tank off a Blackbird (fuel injected) whilst
keeping (almost) all of the fuel in the tank?

 

1. When I needed shims for my last bike the main dealer mechanic was

Flawless logic and if I could, I would!

Although I don't reckon it's quite the same - I wouldn't open myself up just
to see if I needed to take my appendix out - there would be symptoms and
hopefully they'd go away afterwards.
With the bike I wouldn't know until probably much later, when my valve
burned out, that they hadn't been checked.

Of course it's possible I'm being too cynical and I'm sure there are some
honest and trusworthy main dealers.

 

I checked the valves on my CBR and they were a bit tight, however I
did not have a suitable spanner or patience enough to bother adjusting
them. I am now in the position that I know they are a bit tight but I
have not got around to adjusting them ! I would think that you can at
least check them your self; get them adjusted if they do need doing. I
have to check my Birds' valves at some point, it's on about 25k so who
knows if they have ever been looked at... I do mainly motorway riding,
correct me if I'm wrong ( as usual) but I suspect many short
journeys would more likely lead to the gaps getting too big. I'm
awaiting that elusive weeks holiday at home, when I will have the
time and inclination to catch up on all my vehicle maintenance before
I do mine ! I guess part of the reason for having 16 of the things is
that they are less likely to burn out if you neglect the maintenance ?

Simon

 

Seconded. Patrick at Pointe de Corde checked the valve clearances on
the Tart as decreed at 10000 Kms. He was pleased to report they didn't
need adjusting. This is good news in view of cam wearr problems on
some early (pre kit evo) motors. Apparently they won't need checking
again until 30000 Kms.

 

And they don't help in making the bike run well either, particularly with
ECU controlled fueling which takes its cues from (among other things) the
amount of shite coming out of the tail end iof the exhaust.


Tight valves will give little

As can a leaking exhaust system.


--
Beav

VN 750
Zed 1000
OMF# 19

 

You've never had a job done at a garage that was't *actually* done? I'd say
you've been lucky.


--
Beav

VN 750
Zed 1000
OMF# 19

 

This sounds bad.
Are there likely to be other symptoms before this happens? I only ask
because I'm pretty sure the Bus should have been checked at the 16K
service. However, there's no mention of it on the invoice. Mileage now
at 22K and I'm getting a weird hunting/surging with a constant
throttle at low revs, the cause of which I've so far been unable to
identify. Last week stripped the whole of the fuel system down to
check for clogged filters, which were fine. I've also fitted new plugs
and cleaned the air filter.

 

This sentence makes as little sense as any of the foregoing, but is a
prime example of the ignorance of the majority of vehicle users, and
why so many service workshops (allegedly) can get away with bullshit
and poor workmanship.

Neglecting maintenance is a fool's creed, all the more so if the
neglectful person does not understand the first principles of the
operation of the machine to be maintained.

 

I wish the utter fucker who owned the FJ before me had done this. I
had to dremel all around the studs on #2 flange to get the downpipe
off.

<fx: waves to Andy Hewitt>

P.

 

Are you calling me a ****?

--
AndrewR, D.Bot (Celeritas)
Kawasaki ZX-6R J1, Aprilia RSV-1000R (11th August), Fiat Coupe 20v Turbo
BOTAFOT#2,ITJWTFO#6,UKRMRM#1/13a,MCT#1,DFV#2,SKoGA#0 (and KotL)
BotToS#5,SBS#25,IbW#34, DS#5, COSOC# Suspended, KotTFSTR#
The speccy Geordie twat.

 

This is UKRM.

Do you *really* need an answer to this question?