Now that's going to be expensive

[Rob Farmer]

Glad it's not my bike.

My mate put his bike away a few months ago. Tried to start it a while later and just got a clunk from the starter.

We put it in my garage this morning and whipped the head off

There's no sign of any scouring where the valve seat sits in the head but there's a section of valve seat missing completely - must have gone down the exhaust. It looks as though the missing piece disappeared when he last rode it and then the rest of it dropped out when the engine cooled. I'm hoping the heads salvageable once a new seats fitted..

 

[Voyager]

Ooooh Nasty

Any ideas on what caused it (overheating, over-slack tappet causing hammering, overtight tappet causing searing of the seat) ??

Will he be getting all the seats done as a precaution ??

Bob.

 

[(RIP) maverick]

Ouch that's not a cheap fix!

 

[Rob Farmer]

Ooooh Nasty

Any ideas on what caused it (overheating, over-slack tappet causing hammering, overtight tappet causing searing of the seat) ??

The bikes been running great. Apparently he fired it up for a few minutes without riding it, shut it down and next time he went to fire it up it wouldn't turn over. I've just retrieved the missing part of the valve seat from the silencer so all the parts are there. It looks as though the valve seat simply cracked and then dropped out. Lucky he wasn't riding it.

With a bit of luck two new valves seats a pair of valves and new guides will see it back on the road. it's a 1981 36,000 mile bike so was due for it's top end overhaul.

 

[(RIP) Proff]

As long as it was spotted before firing the bugger up, it's not a bad job..
Valve seat and fitting here in Devon £50
Valve £45
Head gasket £5..
NOW if it had gone whilst doing 60 odd mph it could have been a new engine

 

[Rob Farmer]

Doesn't bare thinking about does it

It's only done a couple of 1000 since he bought it off Shapeshifter so we'll blame him

 

[Uncle Rob]

It's only done a couple of 1000 since he bought it off Shapeshifter so we'll blame him

and I'll blame you I only had it for 3 years,so must still be under your unlimitted millage warranty

 

[JJH]

I just wonder is it an unleaded issue? the bike is 1981 but could have been built earlier. I have a 79 bike that needs leaded fuel. Might be worth checking the other side. JJH

 

[(RIP) Proff]

The bit thats broken IS the Unleaded conversion


I only worry if the tappets tighten up, otherwise I never convert them...

 

[Rob Farmer]

and I'll blame you I only had it for 3 years,so must still be under your unlimitted millage warranty

I got it from a bearded bloke in the west mids so it'll be Proffs fault.

 

[Rob Farmer]

These are the original valve seats. No sign of any regression.

 

[Uncle Rob]

any way when Robbie bought the bike there was no mention of him ridding it,glad I got rid of the old rust bucket

 

[fayeslane]

any way when Robbie bought the bike there was no mention of him ridding it,glad I got rid of the old rust bucket

Should be ashamed of yourself offloading a bike that condition to an inmate