Did you ever get new engine shims?

[MondoRich]

Just checked my valve clearances 34k no change since new.

Have you ever needed new shims and at what mileage?

 

[OMG!!]

Clearances done at 46k, no shimming required, although it may have been done by one of the previous owners. Partial Service history did not show any being done.

 

[siddo]

They told me they replaced some on my last service at 28k miles.

 

[DJ123]

I had one done on my bike about 2 years ago only a minor one, probably about 50k miles. Now on 75k and no further adjustments needed yet.

 

[MondoRich]

As the shims wear do the gaps you’re measuring get bigger or smaller?

The valve seats might be getting worn so I think the gaps would get larger as the valve sits tighter in the head? Or is it the other way around?

 

[OMG!!]

According to Ai.....As the shims wear, the gaps you're measuring generally get bigger. This is because wear on the cams and followers tends to increase the gaps, while wear on the valve heads or seats can decrease them, but overall, the trend is towards larger gaps.

 

[JJH]

There’s many people who THOUGHT they got new shims. A certain bike shop was famous for it. JJH

 

[Guru Gora]

The risk v cost ratio is way out most of the time.

1000 quid if it’s awkward to get to, only to say, ‘ah that’s ok’

I’d rather pocket the money.

 

[JJH]

The risk v cost ratio is way out most of the time.

1000 quid if it’s awkward to get to, only to say, ‘ah that’s ok’

I’d rather pocket the money.

Many do. I’d love to know the % of valves that need clearances adjusted. And while some engines are noted for needing attention others are noted for staying within tolerance. Of course it’s really only gaps that tighten that can cause damage. JJH

 

[seahorse]

Different bike but my F650 twin had none changed in 75k miles.