Don Stafford's " Alstar " 4V JAP head

[JAP 454]

A year or so ago, there was a thread about an OHC 4V JAP and during the discussion, the Don Stafford 4V head conversion was mentioned,
Quote from Pete 52,

“Great topic, now who is gunna pull a pic of the other conversion, I'm sure I saw it at Griffith one year-pushrod operated and rockers lubed with a grease nipple at the time (apparently to be oiled delivered later).”

I also had an email from the fellow that did the engineering on the conversion, but , unfortunately, I’ve lost that email.

I mentioned that, some years ago, I had seen an article, in a magazine about the head and today I found the magazine , Trail and Track , August 1976, Here’s part of the article and a couple of pix,







The development of the conversion was negated by the introduction , in that year, by the 4V pushrod Weslake

And also found this pic in the same magazine, Alstar TT 500



The Don Stafford "Alstar" frame was a copy of the Elstar, however, the Alstar used taper roller steering head bearings, I used an Alstar diamond in my Elstar after wrecking mine bigtime in a big prang in the final of the '75 ??  NSW Unlimited titles at Young.

Foss

[Curly3]

Interesting article, that one looks like the rockers are oil fed, unless the hose lead to a remote nipple near the steering head.
I wonder where it is now and if they still have the frame jig's?
Thanks Foss.

[Slider29]

 I've got the email Foss,  I'll send it back when someone shows me how
          Regards  Mark

[JAP 454]

Mark,
Just highlight the email, click on forward in the toolbar , an email pane will open,and then put in my email address inthe "to " line then hit  send.
I'd love to have a copy, I forgot I had forwarded it to you.

Slides , I think the email explains the bit about the rocker lubrication
Foss

[JAP 454]

Ok Guys, thanks to Mark and Richard , we now have the full yarn, here it is from the engineer who designed and made the Alstar 4V head.

You are pretty much on the money with the 4v Jap with grease nipples.
Don and I were in Hartwell club and he was a mate and a VERY good rider both road race and short circuit, I have always been interested in racing engines and thought the Jap could be better with a little help.

I designed and made the head for Don’s 84S and every time he rode it we either got a record or equalled it however we did not finish too many races as it kept breaking exhaust pushrods for no good reason that related to any design deficiencies that I could find.

By the end of that season the factory 4 valve engines were coming out and we did not pursue the Jap any more.
The very last time we had the engine apart I was looking at yet another broken exhaust pushrod looking for a reason when I saw an Allen head capscrew which held the magneto drive cover was polished on the end of the thread, what had happened was that screw which should have been in another part of the case and a shorter one for the case at the back of the pushrod.

There was clearance behind the pushrod except when the engine was at high revs ( and push rod load ) and the pushrod flexed sufficiently to rub on the too long screw and give it a stress failure point which it did.

The 4 V head interestingly had a second life.

I had a 900 SS Duke road bike at the time and Bob Brown used to do what Bob Brown did and one day while in his shop in Coburg I was looking at the Pantah Duke he raced and I thought that the bore size looked familiar and sure enough it was the same as the JAP, I showed Bob the head and by the end of the day he owned the patterns to the JAP head which he used as the basis for his 4 valve Duke.
Bob converted it to twin overhead cam configuration and did a very good job too.
Kevin Magee rode it with a fair amount of success.

I still have the head and will get around to putting it on a JAP when I can find one.
Don Stafford was also the agent for the Rokon competition dirt bikes on which I had my first and last dirt experience at Granite Park and scared myself shitless and decided I should stay as a happy C grade road racer.
I have no photographs of the engine and if you find one I would love to have a copy
Regards
Richard Bendell.

Many thanks for that interesting yarn, Richard, you have answered a few questions.

Foss

 

[Curly3]

That's what I based my comment's on Foss.
I thought maybe the original had 4 seperate grease nipples on the rocker cover.
The tails sticking out look more like oil tubes to me but the central feeder hose goes pretty high up the frame.

[JAP 454]

That's right Slides, in the body of the article , it describes a small oil tank feeding the pipes sticking out of the rocker-box, Richard , in his email , says it was right about the grease nipples, which I'm guessing was the prototype, I've sent an email to Richard, offering to photocopy the whole article and send to him as he hasn't got a photo of the engine, when he replies I will ask about the grease nipple rocker lubrication as both Pete and I remember them.
Anyway, all interesting and a bit of OZ DT history, must ask about the Alstar frame jig's !!!
Foss

[Stan S]

Is that the same Richard Bendall that was the brains behind Motec and also built the Daytona Kit cars that were the demise of Peter Brock?

Stan.