j.a.p ohc parts

[k2000x]

yep jim its the same motor as the blue hagon...how can you tell year model for hagon frames

[jimg1au]

HI
its a 1978 dohc 4 valve jap.only made for 1 year
most engine parts i think are the same as 84s but dont know anything about the cam gear

[k2000x]

cameron racing engines in uk make new parts there sending me price list and product list

[pancho]

in the olden days when i used to read any mag that had any thing about fast machinery the current gospel of the american hot rod mags was "if it won't go CHROME IT", so i'm with jim on this, but no need for chrome just polish it then put it in the lounge room. cheers wally.

[52]

I'm with you Jim, did a bloke named Tony Lacey win an Aussie title at Seymore on one? Dunno bout Firko's Jawa obsession, just cause it came from Europe don't mean it's the duck's guts.

[Curly3]

G'day Pete, that would have been or 1979 or 80, I rode at that meeting myself on a KX 250 A5, didn't do any good. I didn't realize Tony was riding a 4V JAP though.

[52]

Yeah Curly I'm sure it was a 4-valver, not sure bout ohc I think they were pushrod operated, will check with Norris (79).I rode there as well (Hagon Yamaha)- Chris Watson won 250 (I think).Track was rough.

[firko]

? Dunno bout Firko's Jawa obsession, just cause it came from Europe don't mean it's the duck's guts.

Not really a Jawa obsession Pete, I couldn't give a hoot either way. I'm just relating what most experts think of the 4v ohc JAP. The pushrod JAPs however were great old things. I'm pretty sure Lenny Norris used a 4b JAP and not a cammer but I'll cop it if I'm wrong.

As it is right now, I have more Japanese bikes in the collection than Euros. No bias either way from this old fella if that's what youre alluding to.

[52]

Thought I'd get your hackles up Mark. Len never used a 4-valve JAP but he has a good memory.Having owned 2 JAPs and a Jawa during the 70's, the JAP is my pick of the 2 motors on short circut.

[52]

Just a little note bout the JAP, got the info from Len Norris.Tony Lacey won the unlimited title in 79 @ Seymore using an 84C (factory 548cc JAP) with a Frazer tuned factory ohc top-end running a blue magnum carb, in Len's opinion it was just too late in the day for J.A. Preswick, Weslake already on the scene, but the mighty JAP still performed that day,Hurrah! Len's first JAP was an 84S short-stroke,his next one was a 4B long-stroke,quickly updated to 600cc for the unlimited class while he rode Kevin McDonald's bikes in the 500 class.They were the days, my last JAP (probably one of the last new one's sold in Aust. with electronic ign etc)got bored to 548 in an effort to keep the 4-valvers in sight, the weapon of the time had to be 588cc Weslake,they just gated so well.Good luck with the rebuild Hoony you probably have a piece of history there, its no boat anchor.

[firko]

Len's opinion it was just too late in the day for J.A. Preswick

That's what I reckoned earlier. They were too little too late. Tony Laceys win would have been one of the few on a a global sense. The engine was built as a speedway motor and in that discipline they were way off the pace. Even though I've slammed the 4V JAP, I reckon it's a great collectors item and something unique for the occasional race or parade but I think K2000X wants a race bike not a show pony. The JAP would be a expensive to rebuild and maintain for a few skids at the vintage races. A 4B or 84s would be fine but a cammer? too rare and hard to find bits for. I still reckon that a Jawa, Godden or even a Wessy would be better both financially and on the track. It's kinda like my V12 Jag. They go OK, look and sound amazing but in the real world, a simple Chev V8 will usually whoop it every time for a fraction of the rebuild costs.     
 Below Hagon 4V JAP photos courtesy of Gus.

[firko]

Speaking of JAPS...I heard from Mike Greenaway in Townsville who tells me he's building a Cheney with a Cooper JAP engine. Apparently the engine is an aluminium barrelled version of the 4b made by Cooper Racing Cars for their little formula 3 cars from the 50's. Now that's a rare JAP.

[jimg1au]

firko
is that brian martins 4v he got his from frazers

[firko]

No idea Jim but the Kevin Fraser sticker might point it in that direction.

[Curly3]

Not to be a pedant but I thought it was J.A.Prestwich.
I think I have a recolection that Fraze himself rode a 4V JAP right towards the end of his long and great career. Gus who, Firko?
I agree with Jim & Firko, straight to the pool room with this GEM.