Valve clearances wear

[Snave1000]

Those who have checked their own valve clearances several times have you find they tighten or slacken? A couple of exhaust clearances although all were in spec are on tighter end of clearance, wondering is it worth adjusting to more mid/larger clearance if next 16000mls will take it over..

[Art]

Only checked mine the once at 48,000 miles, results below. There is nothing in the service history to suggest they'd ever been checked prior to my ownership.

[Snave1000]

I’m assuming they’ll tighten , guess I’ll know in another 16,000.

[FLIZ]

 Generally they tighten.

[keithriley]

Originally Posted by Art

Only checked mine the once at 48,000 miles, results below. There is nothing in the service history to suggest they'd ever been checked prior to my ownership.

Funnily enough I've just checked mine during an engine strip down, and found exactly the same, Cylinder 4 exhaust valves down on clearance, all others within spec.

Keith

[Art]

Not the first time I've heard of only cylinder four being out of specification

[Davy]

Hi Guys,
I bought a CBF1000A6 (2006) about 4 years ago. There is no record that the 16,000 mile valve clearance check was done. The bike now has 26,000 miles on the clock so I decided it was time to have a look. This is my first time ever to do this. The following are the readings:

Intake tolerance – 0.13 to 0.19 mm i.e. all within tolerance reading at 0.15 to 0.16mm
Exhaust tolerance – 0.29 to 0.35 mm i.e. all outside tolerance reading at – 0.028 mm (except N0. 2 which is reading at 0.33 mm i.e. inside tolerance).

Questions:
1.   As the Intake is perfect after 26,000 miles. Is it possible that the Exhaust has always been like this?
2.   Is it worth re-shimming for this level of out of tolerance or just leave it for another 10,000 or so?

Note: the bike starts, idles, and rev’s with no issues so I don't want to mess with it if I don't need to.

Thanks for your help in anticipation.

David

[keithriley]

Originally Posted by Davy

Hi Guys,
I bought a CBF1000A6 (2006) about 4 years ago. There is no record that the 16,000 mile valve clearance check was done. The bike now has 26,000 miles on the clock so I decided it was time to have a look. This is my first time ever to do this. The following are the readings:

Intake tolerance – 0.13 to 0.19 mm i.e. all within tolerance reading at 0.15 to 0.16mm
Exhaust tolerance – 0.29 to 0.35 mm i.e. all outside tolerance reading at – 0.028 mm (except N0. 2 which is reading at 0.33 mm i.e. inside tolerance).

Questions:
1.   As the Intake is perfect after 26,000 miles. Is it possible that the Exhaust has always been like this?
2.   Is it worth re-shimming for this level of out of tolerance or just leave it for another 10,000 or so?

Note: the bike starts, idles, and rev’s with no issues so I don't want to mess with it if I don't need to.

Thanks for your help in anticipation.


David

Hi David,
I would have no issues with continuing using the bike like this, as you say there is negligible error there, but it will have to be tackled sometime, maybe a few years down the line.
I'd also argue if you're this far in to it now, is it not worth just biting the bullet and getting the job done. I personally don't ride in winter and so use it as maintenance time.

Regards

Keith

[Davy]

Keith,
Thanks for your reply. I think you are right. I might as well just get it done. Have you any recommendations who to get the shims from?

[keithriley]

The ones you need are ‘typical’ Honda 7.50mm (or to be specific they’re actually 7.49mm) shims, but you won’t know what thickness you need until you see what’s currently fitted. I bought mine on eBay for about £3 each.

Keith