Valves for Velocette MAC

**ellipsis** · 15th January 2016, 11:04

I dropped a valve on my Velo and am in need of an exhaust and inlet valve for a MAC. Standard valves I believe.
Like an old wise fisherman once told me , fish your feet before before heading off in a boat. Maybe someone knows of something around here,before I start on the extensive net search?

**Grumph** · 15th January 2016, 11:14

If you can piece together some specs from the wreckage: stem dia, head dia. rough overall length, I'll see what i can adapt.

Bring the damaged piston to the pre 82 cup meeting too please.

**ellipsis** · 15th January 2016, 11:45

Will do. The tough old bird despite the valve bouncing around and smashing shit out of the piston and banging the head a bit is relatively cool. I have the stem and head in two bits.

**Grumph** · 15th January 2016, 13:44

Originally Posted by ellipsis

Will do. The tough old bird despite the valve bouncing around and smashing shit out of the piston and banging the head a bit is relatively cool. I have the stem and head in two bits.

This is where I'm supposed to say "call that damage ? Now this is damage" and post a pic which would embarass us both...so I won't.

**sidecar bob** · 15th January 2016, 13:50

PM Swarfie, I think one of his did the same thing recently.
He will have the answers & probably the parts too. Fairly clever chap he is.

**nodrog:Me** · 15th January 2016, 16:07

Originally Posted by ellipsis

I dropped a valve on my Velo and am in need of an exhaust and inlet valve for a MAC. Standard valves I believe.
Like an old wise fisherman once told me , fish your feet before before heading off in a boat. Maybe someone knows of something around here,before I start on the extensive net search?

http://www.outdoorspares.com/Genuine...ne-Inlet-Valve

**Grumph** · 15th January 2016, 18:50

Originally Posted by sidecar bob

PM Swarfie, I think one of his did the same thing recently.
He will have the answers & probably the parts too. Fairly clever chap he is.

I'll endorse this though I think you may have spoken to him at Levels anyway. It gets you plumbed in to the NI velo clique who will have the right ideas on what to use. Do not ever use original parts in it....by the time they were making them their machinery was worn out. Modern parts are better made from better materials.

**J.A.W.** · 15th January 2016, 19:57

Originally Posted by Grumph

This is where I'm supposed to say "call that damage ? Now this is damage" and post a pic which would embarass us both...so I won't.

Jeeze, can those ancient Pomgolian pussers even rev hard enough to do 'real damage'..

The only 'classic' 4T Honda I owned was a Yoshimura modified XL 250 ( ported head/hot cam/big bore slipper hi-comp piston/stiff valve springs/big Miki carb/trick 'supertrapp' pipe, & slotted into a CR chassis.. it was a bit of a precursor of the current 4T 250 MX..

It had a bad habit of breaking the stock cam-followers which weren't up to the high speeds/heavy duty forces involved, but I finally sold it when it punched a valve head through the Yoshi piston @ ~ 12-14K rpm.. & wrecked the head..

I kept that piston as an object d' art/object lesson to run 2Ts - for years, 'til I accepted an offer to buy it - from a Yoshi collector..

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**rudolph** · 1st February 2016, 16:17

I have a 1949 BSA witch has a Chevrolet exhaust and a Ford inlet valve, I had the keeper slots moved down and the stem shortened by a guy at my old work, things for thees old bikes can be made for very cheep

I got the valves from the scrap bin at an engine reconditioner.

**ellipsis** · 1st February 2016, 16:36

...all sussed now... thanks to Grumph, swarfie, Sidecar Bob, and me, deciding which way I would go...now I've gone...thanks...anyone have a 5TA (68.5 mm) piston to sell me?...so I don't have to leave my chair...

**rudolph** · 1st February 2016, 17:13

Originally Posted by ellipsis

...all sussed now... thanks to Grumph, swarfie, Sidecar Bob, and me, deciding which way I would go...now I've gone...thanks...anyone have a 5TA (68.5 mm) piston to sell me?...so I don't have to leave my chair...

have you tried classic cycles in upperhut?

**ellipsis** · 1st February 2016, 17:20

Originally Posted by rudolph

have you tried classic cycles in upperhut?

I'm hoping to not have to go offshore, but I will if I have to...thanks...

**Grumph** · 1st February 2016, 18:23

Originally Posted by ellipsis

...all sussed now... thanks to Grumph, swarfie, Sidecar Bob, and me, deciding which way I would go...now I've gone...thanks...anyone have a 5TA (68.5 mm) piston to sell me?...so I don't have to leave my chair...

tried Alan Bland yet ?

**ellipsis** · 1st February 2016, 18:39

...got caught in a large set of viral road cones that hindered my progress towards his area, then got spat out and ended going somewhere completely elsewhere...it was 30+ so I squawked at other drivers and went to the Tai Tap for a beer...will try another approach road soon...6 weeks for CHS to do the valves, head, guides etc...that timeline suits my empty pocket...