A wee Matchless project

[Rannsachair]

aye that would be ok with a wee bit tig patience it should be easy , no left much for sealing on that flange must be about 34 mm that port is there a bigger valve too, that will sook spuggies in there on full chat
oh spuggies " sparrows for our southern friends

Think I would be wasting my time trying to MIG it? I do not have TIG and was rubbish at it last time I tried almost 40 years ago!

That inlet is 38mm! I was thinking of making the carb adaptor with a smaller bore and adding a spigot with an or ring groove to seal in the bore. The Amal Monobloc 389 I have for it is only 1-5/32" bore.

They have cut down the guide too:

And some work on exhaust port too:

A few of the engine bolts were drilled for wiring them, so suspect it has been raced at some time in its life.

 

[Seadog]

The 600cc was known as the "TCS," as I'm sure you know. I ran my 500 with SH cams and it used to go well. It'd happily sit at 75 and still pull when the throttle was wound back. I had an indicated 95 on the M4.

 

[slim_boy_fat]

that will sook spuggies in there on full chat
oh spuggies " sparrows for our southern friends

They were 'spurgies' where I came from, not that it matters......

 

[Rannsachair]

They were 'spurgies' where I came from, not that it matters......

Spuggies for me.

 

[slim_boy_fat]

Spuggies for me.

Regional/dialect differences then, it was The Doric for me.

 

[ronan]

Ebay bargain delivered today: good second hand set of tappets and bushes to replace knackered ones.

Tool in post above to remove the old ones.

Is that book any good Tom, the Mick Duckworth one ?

 

[ronan]

Absaf | Matchless G80 Complete engine

 

[Rannsachair]

Is that book any good Tom, the Mick Duckworth one ?

It is pricey, though I enjoyed it, I worked with a couple of guys in the book so am more interested in all the details than most.

 

[ronan]

It is pricey, though I enjoyed it, I worked with a couple of guys in the book so am more interested in all the details than most.

I might have to treat myself

 

[Seadog]

I collected enough parts to build a G85CS engine: including new crankcases, barrel, conrod, genuine hi-comp piston, mainshafts, and head from Russel Motors Kent storehouse. I had some cam blanks reprofiled to the short circuit CI/CE profiles, and also acquired a brand new Wader mag.

I never did get around to building it, or the special that it was intended for, but let Maurice Hocking build the engine, then decided I couldn't afford the £400 he wanted and let him have it for that price plus the many other original parts that I'd collected...

 

[Rannsachair]

I collected enough parts to build a G85CS engine: including new crankcases, barrel, conrod, genuine hi-comp piston, mainshafts, and head from Russel Motors Kent storehouse. I had some cam blanks reprofiled to the short circuit CI/CE profiles, and also acquired a brand new Wader mag.

I never did get around to building it, or the special that it was intended for, but let Maurice Hocking build the engine, then decided I couldn't afford the £400 he wanted and let him have it for that price plus the many other original parts that I'd collected...

Hope that was a very long time ago, worth a fortune now.

 

[Seadog]

Around 1996 if I remember correctly. Still worth a lot more than that even then. The other spares alone must have been worth two or three hundred. I also had a new, original, pressed alloy chaincase and various other ultra rare pieces. It was all going to go into a P11 frame.

To say nothing of the 750 I was going to build using a "Pluto" frame.

 

[minimutly]

No outer ring, I actually saw someone advertising the AMC conrod reaming tool on ebay, but I was outbid.

My auto advance had seen better days, I fitted a better second hand one of my other Matchy:
View attachment 295439
I was thinking of welding the worn faces and filing back to shape.

I am using CS cams in the 500 engine and still not decided on using the perhaps overported head that came with the engine:
View attachment 295440

I do not want to go to far with tuning, just want a reliable engine that accelerates better than my 350 and will sit at 65 without feeling thrashed.

That's been properly trashed.. how much of a short turn radius has been left? It looks minimal, in which case any decent gas flow capability has been sacrificed, all to lose even more power with oversized port. I'd be looking to bore it clean and insert a tube, then shape that to match internally (not easy)!

 

[graffian]

Mig will be fine on the advance mechanism.

 

[ronan]

That's been properly trashed.. how much of a short turn radius has been left? It looks minimal, in which case any decent gas flow capability has been sacrificed, all to lose even more power with oversized port. I'd be looking to bore it clean and insert a tube, then shape that to match internally (not easy)!

I've seen it done with Devcon, building up the port floor into a "D" shape.

 

[Rannsachair]

That's been properly trashed.. how much of a short turn radius has been left? It looks minimal, in which case any decent gas flow capability has been sacrificed, all to lose even more power with oversized port. I'd be looking to bore it clean and insert a tube, then shape that to match internally (not easy)!

Someone has gone mad with the porting!

 

[ronan]

Any danger of the valve seat falling out due to lack of support ?

 

[Rannsachair]

Any danger of the valve seat falling out due to lack of support ?

I don't think so, going by the amount of carbon in the head it has run this way for some time.

 

[ronan]

It wouldn't be off a speedway engine run on methanol ? I seen a few of them and they have huge ports as they run throttle wide open.

 

[ronan]

I subscribe to this chap in Wales, lovely area he lives in. Anyway he makes a living fettling old bikes and upped this an hour or two ago.