JAP 4 Valve Advert

[kdx 175]

you know were i can find photo of alf land speed record jap

[JAP 454]

Now wouldn't the Scott be great to hear at full noise lapping the Headquarters !!, Me Dad has a thing about Scotts, a Flying Squirrel I think.
Foss

[JAP 454]

you know were i can find photo of alf land speed record jap

KDX, I can't find anything on his LSR bike , but here's his blown V twin dragster



And here's the man himself


Foss

[Slider29]

Foss, that 4v JAP Longtracker is bloody beautiful. I reckon that the
carby is an AMAL Concentric MK2 40mm. What do you think? I'm sure we're
seeing the same thing here.
cheers  Mark

[JAP 454]

Yeah, Mark it's a MK 2 concentric alright, a bloody big one too, Doncha reckon Alvin would like the Scott ??, big two stroke an' the colour ??
Foss

[Slider29]

Yeah Foss, Alvin will get movement when he sees the Scott.  It sure is a cool lookin' bike.

[mustanggrahame]

I've got a 1926 Flying Squirrel. It has telescopic forks like the speedway one but extra bracing on the front. Also has a full frame with the tank being the top tube of the frame. 3 speed gearbox.
I did have a pre war JAP, but thought I would never get to use it so sold it about 10 years ago. My first introduction to early speedway stuff was firing up an early 30's 4 valve Rudge in a cobblestone lane way in Geelong. I was 18 and had only really raced MX. It was an eye opener how hard this very old bike went. It made me think about the old stuff in a new light.
Cheers, Grahame

[JAP 454]

It's coincidence that you mention a Rudge Speedway bike, Grahame, ( I've seen and heard a video of a Rudge skidder being fired up, a really rorty sound !!)
Here's a pic , from the JAP engine page, courtesy of Bennie, Dutch on this forum , of a Jap fitted with, in some's opinion, a Rudge 4V head.
Check out the 2 into 1 exhaust.
Is there any more info on this engine , Dutch ?


Foss

[pancho]

 That's interesting!

[JAP 454]

Slider29 pointed me at this pic of the Erna V twin Wessie Longtracker, imagine turning the wick up on this !!



Oh, and while you're at it, have a look at this link, Speedway, Longtrack, MX Sidecars, Dragbikes, road racers, all Wessie powered

http://www.diagnosis2012.co.uk/weslakes.html
Foss

[Dutch]

That JAP engine is made by German tuner Siegfried Priehs from Rodenkirchen.
Yes the JAP engine is fitted with a Rudge 4V head, and the bike was very succesfull ridden by Rider Hans von Weyhe in the early seventies.
Tuner Priehs also made later his own speedway / engines (a Dohc 4V and a Sohc 4V) under the name SPR.

[Dutch]

Here some extra info on that Dohc 4V grasstracker, 
This frame is made by KeithJarvis (England)
The counter-shaft and the swinging-arm are co-located, so there is constant chain tension.

[JAP 454]

Thanks for the info, Dutch,
Foss

[Slider29]

The BLACK ERNA V twin Weslake,..... 1000 cc, 120 HP, 0 to 170 kph in 6/7 sec
I don't think that I would like to pilot that missile.

[JAP 454]

Yep, that would tend to pucker the orifice somewhat , wouldn't it ??
Foss