What the???

well, it certainly is colorful I guess...

email (option): cas.vanderwoude@gmail.com

its a start to bring it back to life

email (option): roger.beck@node6.com

Or this perhaps?

231599136574

email (option): fozzie001@hotmail.com

This bike keeps changing hands..Last year it was in Devon...before that near London....

At one time the asking price was £15,000!!....I think at that point someone had been sniffing the Methanol rather than putting it in the fuel tank...

At least currently it is nearer a realistic price...

I'd actually like to see this thing in action as I don't really believe the power or estimated top speed claims that have been made at various times, all without any documented back up such as dyno tests etc.

Nevertheless, I stand to be corrected if I'm wrong...

It seems odd to me that none of the owners who say it's such a great bike want to keep it...or have run it in anger... ....Ian

email (option): ian@wright52.plus.com

Yes, this bike keeps appearing on eBay,
And every time it looks more tired... (-:

I think I asked before, but I do not think that there was a definite answer...

Is there any benefit of moving the spark plug to the center of the head,
Above the piston, as done to this bike here, or is it just better for methanol?...

Noam.

email (option): noam10@gmail.com

"Nowt so query as fowk" - said in a Yorkshire accent.

Cannot really comment at the two Ebay offerings, as my first road bike was an arrow engine into a D3 bantam frame - with some Honda tank or other - probably looked a lot worse than these ...

RE central spark-plug - the theory goes, that the shorter the flame front - or distance the flame has to travel, in a combustion chamber, the less advance needed and hence more power (spherical combustion chambers etc....).

One thing I do read about SV's is that most conventional tuning doesn't work - HD did extensive dyno testing on their 750 SV's for USA dirt-track, and the basically found they simply had to try absolutely ANYTHING and see what happened - the cam timing is a case in point ...... WILD!!!

One major problem is fuel/air flowing straight out the exhaust port during valve overlap @ TDC - mainly caused I suspect, by the central inlet feeding the two cylinders. All made worse by the large squish areas and concentrating the combustion area over the valve.
In this case the plug gave more power when placed in the center of triangle formed by the squish band and the inlet/exhaust valve.

The road race KR HD SV's had separate updraft inlets to each cylinder (+damn great air filter's to stop goffers from being sucked in) - I've never seen any internal pix of these engines, but the spark-plugs look as if they are nearer the valves, than the dirt-trackers ...?

Simply, you are only guessing until you cut, weld, grind and try.

email (option): ginantonik@tiscali.co.uk

['Simply, you are only guessing until you cut, weld, grind and try.']...

I couldn't agree more...If there was ever a 'black art' it's tuning sidevalves.... ..

Tuning information is available from the past but there is virtually nothing from the current time...

H.D and other information can help with mapping out the basic principles but when it comes to applying the ideas to specific engines it is largely guesswork, and if you think you might have come up with something different you're on your own!...

Be prepared to expend considerable amounts of time, effort and money without any guarantee of a good result...Ian

email (option): ian@wright52.plus.com

Sums up tuning/racing in general really ..

No one could understand why our Greeves/Arrow/Triumph650/BMW1050 and finally our YR5/TR3/TZ 350 yams were so damn fast (86bhp at back helps) - hours and hours of setting up carbs, pipe lengths, etc. + 26 year meetings a year, was why .... !
+ 45 years of racing..
And the number of times we were told 'how to make it faster' - usually by the people we beat!

And they are still telling us (as in yesterday) how to make a CCM or B50 faster ......

email (option): ginantonik@tiscali.co.uk

Interesting.

Thanks !

Noam.

email (option): noam10@gmail.com