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Flyingpony
17th July 2007, 12:03
There's $BANG$ and tapping, what other symptoms indicate that valves need adjustment or are caused by valves not being in correct adjustment?

Thanks.

jrandom
17th July 2007, 12:05
Chunks of piston flying out the exhaust?

vifferman
17th July 2007, 12:07
Chunks of piston flying out the exhaust?
That's usually a symptom of the wrong heat range for the spokploog, or having a Honda CCT fitted...

James Deuce
17th July 2007, 12:09
Actually I get more worried about an absence of noise when it comes to a valve train.

Crisis management
17th July 2007, 12:19
Anyone heard of a maintenance schedule?

xwhatsit
17th July 2007, 12:19
Actually I get more worried about an absence of noise when it comes to a valve train.



<hints id="hah_hints"></hints>I heard that too. Don't modern engines tend to close up on tappet clearances, rather than get further apart like older ones?

vifferman
17th July 2007, 12:23
<hints id="hah_hints"></hints>I heard that too. Don't modern engines tend to close up on tappet clearances, rather than get further apart like older ones?
Yeah, the valve seats wear slowly, decreasing the gap.

Flyingpony
17th July 2007, 12:49
The valves have always been quiet since new, but recently they're making a tapping noise. Comparing the clearances gaps from last time, they have closed up.


Anyone heard of a maintenance schedule?
What is the maintenance schedule for valves?

Paul in NZ
17th July 2007, 13:08
There should be a schedule in your owners manual. (ie every 6,000 km etc) If the clearances have closed up dramatically I'd be concerned, if it's just a little I'd reset them and monitor the situation. Some vehicles need them checked regularly and others solider on for yonks - no idea what the go is with yours though. Any suzuki dealer should tell you...

Crisis management
17th July 2007, 13:19
What is the maintenance schedule for valves?

As the old bugger above me says.....

My somewhat succinct point was that if you actually carry out the maintenance as scheduled on the bike then you are aware of progressive wear on the various components and can plan replacements / repairs in advance.

Not trying to be a smart arse, but if we all maintained them as they are intended a lot of grief would be avoided.

tri boy
17th July 2007, 14:04
Lack of valve clearance also leads to lack of oil to cam followers etc, get it done asap.
Once the hardfacing has been worn off followers/cams your in to a job twenty times more expensive.:shit:
Maintenance schedules (for all machinery) are put in place to save the owner money, ignore it at your financial peril.

Conquiztador
17th July 2007, 16:58
There's $BANG$ and tapping, what other symptoms indicate that valves need adjustment or are caused by valves not being in correct adjustment?

Thanks.

In todays bikes that use shims to adjust clearance:
- Overheating of head as burning fuel escapes through the not-fully closed exhaust valve
- Hot/red header pipe of same reason as above
- Loss of power
- Valves starting to hit piston as gap too small and so valve is opening too much and staying open too long/opening too early. Mainly in high compression motors that do high revs.
- Mis-colouring of spark plug as a result of poor compression leading to spark plug failure
- Not wanting to run cleanly at high revs as compression low/valve timing out as a result of wrong gap
- Tricky to start as compression low
- "Bangs" in exhaust

In older bikes that use tappets:
- Noise
- When using kick start harder to kick as valves open too late and close too early
- Runs like crap
- Backfiring

Probably more but these are the ones you would normally notice without opening up rocker cover/head.

Flyingpony
18th July 2007, 13:05
Thanks all. That's quite a range of valuable knowledge :yes:

limbimtimwim
18th July 2007, 13:15
Bike like yours, should be a cheap job anyway.

Not like my RVF.

I'm taking donations people!!

shyboy
21st July 2007, 15:37
have u tried using 95 or 98 octane fuel?? Might be just poor fuel causing detonation.(knocking and banging)