What are the early symptoms valves need adjustment?

[Flyingpony]

As per title, how do you know they're due before the x-mileage mark has rolled over?

Is it when:

• Fuel consumption worsens
• Engines starts to back fire
• Engine starts to stutter
• Head of engine starts making the occasional tiny metallic clicking sound
• Head of engine makes metallic rattles
• Other?

After how many km do most people check their valve clearances?
I heard bikes are every 6,000km but cages are 20,000km?

I last checked my 4,000km ago and they were sitting middle of clearance range, so at this point in time I'm just pondering.

This knowledge would be handy to know when test riding 2nd hand bikes.

Thanks.

[degrom]

Backfire can be a lot of things... Timing,carbs sync,valves..

I have noticed that your intake valves can cause backfires in the wrong directions if they are not set correctly.(The valves don't close completely causing a popping sound when the carbs are run with out a air filter)

My 2c.

[Pwalo]

I think hard starting can be a sympton. Check your manual. Most Suzuki four strokes call for a 4k service, so you're probably due for one.

If you're worried take it to your friendly dealer and get them to give the FXR a bit of a fettle up. Also remember to change your oil regularly, and ride your bike as often as you can, and give it a bit of stick evry now and then.

[Kwaka14]

If the clearances close up it can all go quiet also

[Flyingpony]

Thanks.

If the clearances close up it can all go quiet also

,,, and here I thought quiet meant all was good.


Bike behaves as per reliable normal self

Starts first or 2nd pop depending on how many weeks ago the last ride was.

Did the local Akaroa GP in Feb for the first time in 5years

Did an oil/filter change last Saturday. Only mishap was that used oil pours out silently while leaning bike over to extract the last drop

Are thinking about getting somebody more knowledgeable in reading valve clearances to have a look next time.

[Ixion]

As per title, how do you know they're due before the x-mileage mark has rolled over?

Is it when:

• Fuel consumption worsens
• Engines starts to back fire
• Engine starts to stutter
• Head of engine starts making the occasional tiny metallic clicking sound
• Head of engine makes metallic rattles
• Other?

After how many km do most people check their valve clearances?
I heard bikes are every 6,000km but cages are 20,000km?

I last checked my 4,000km ago and they were sitting middle of clearance range, so at this point in time I'm just pondering.

This knowledge would be handy to know when test riding 2nd hand bikes.

Thanks.

All or none of the above.

Modern engines, clearances *usually* close up.

Which probably won't be noticed with a cold engine or on a round the block run.

After a bit of hard caning the valve expands a bit, so it never quite gets closed.

That means combusition gases can leak past it. Causes a slight loss of power, and back firing or crackling in the exhaust.

Oh, yes and after a bit the valve edge starts to glow red hot. Causing detonation, melted pistons and complete engine destruction.

That's what people get for having the silly things in the first place . Sensible engines don't HAVE valves. Or camshafts. Or camchains. Or tensioners. Or any of the other pointless stuff that goes round n round n round n round n up n down n up n down nn n n n n n ......

[Motu]

If the clearances close up it can all go quiet also

Or noisy - the cams have quietening ramps,these slowly take up the clearance....then the valve is slammed open.Too wide or too close and the quietening ramps won't work correctly and you get noise.That's why the clearance needs to be exactly what they recomend.

[terbang]

Forget the symptom, just do it at the recommended interval. As Motu said most of the newer OHC ones close up and that can have issues. I reckon that proactive rather than reactive maintenance is a better way.

[Mr. Peanut]

That's what people get for having the silly things in the first place . Sensible engines don't HAVE valves. Or camshafts. Or camchains. Or tensioners. Or any of the other pointless stuff that goes round n round n round n round n up n down n up n down nn n n n n n ......

Token contradictory statement (with photo).

[Devil]

Yeah noise is a good sign that they need checking. The Trumpy's valve clearance check interval is 20k. Just had the 40k service, 6 shim kits went in. The bike is oh so quiet and smooth again! yum!

[mark247]

As per title, how do you know they're due before the x-mileage mark has rolled over?

Is it when:

• Fuel consumption worsens
• Engines starts to back fire
• Engine starts to stutter
• Head of engine starts making the occasional tiny metallic clicking sound
• Head of engine makes metallic rattles
• Other?

After how many km do most people check their valve clearances?
I heard bikes are every 6,000km but cages are 20,000km?

I last checked my 4,000km ago and they were sitting middle of clearance range, so at this point in time I'm just pondering.

This knowledge would be handy to know when test riding 2nd hand bikes.

Thanks.

Easy answer "tap tap tap tap tap tap tap"

[The Stranger:Me]

Modern engines, clearances *usually* close up.

Sorry, just to clarify. Are you saying that the valve clearances get less with wear in most modern engines.

Just wanted to check cause that would seem to me to be counter intuitive.

[Ixion]

Yes, because the valve seats wear and gradually get hammered into the head. With bucket and shim cam followers there is normally very little wear on the upper end of the valve (excepting exceptions of course, in extreme cases the valve stem can be hammed into a mushroom.

Wear on the valve head and seat shrinkage makes the valve move back, upwards reducing the clearance.