Older 2 stroke fans, anyone remember these tuners?

[BroadsRS6]

Stan Stephens. Beeline Racing. Terry Beckett. Nigel Porter (Sondel Sport). Granby Yamaha.

This was more dad's era than mine but Stan nevertheless put me onto someone who tuned my current little Cagiva.
At 76 Stan is still quite active though with 'things 2-stroke'!

[Rob 131 Sport]

I recall the name ‘Bob Farnham’ as regards 2 Stroke Tuning. There was a book on this and on the Front Cover was National 250/350 Racer Ian Jones. Not sure who tuned his bike / prepped engines.

[Steve Bass]

Stan's shop was down the road from my home. We used to get our 240/400 barrels ported by him until we decided "how hard can it be??" and attempted to emulate the man's efforts with mixed results!!
Learned a lot from him in general chatting and explaining why my bike had let go(again)

[Tango13]

Rob 131 Sport said:

I recall the name ‘Bob Farnham’ as regards 2 Stroke Tuning. There was a book on this and on the Front Cover was National 250/350 Racer Ian Jones. Not sure who tuned his bike / prepped engines.

Bob built my 'FrankenTrumpet' 955/1050 engine a few years back, he was telling me he did his engineering apprenticeship at Mollins the cigarette machine company.

[twizellb]

I can remember Denco.

[rigga]

Stan is still going, will tune, but only on engines he rebuilds I recall, very much downsized from the heyday of two strokes obviously ,his book, "The mechanic who got lucky "is a good read

Had a Honda Cr125 tuned by Terry Beckett, fantastic thing after he'd adjusted the port timing, unfortunately passed away a couple of year's ago now.

Granby are still great for crank rebuilds

[J__Wood]

I had a Stan Stephens X7 back in the early/mid 80s.
Used it for hill climbs and twisty sprints, peaky little blighter.
Always made Hartland Quay/Point just after the start where a low wall keeps you totally safe from the drop off the cliff massive fun as its headlight searched out the sky.

[dibblecorse]

Clive Padgett is another, not as focussed but has built and run multiple 2 stroke race bikes.

Stan Stephens was a legend where I grew up in SE London

[lazybike]

Bill White at Beeline tuned my LC when I was racing, he built some fast sprint bikes, Stan did my KR1S, I did have an ex "works" LC engine from Stan, but it wasn't exactly legal for production racing..

[Tango13]

dibblecorse said:

Clive Padgett is another, not as focussed but has built and run multiple 2 stroke race bikes.

Stan Stephens was a legend where I grew up in SE London

Iirc Clive Padgett was the only person to get a win with an RG500 in F1.

[LukeBrown66]

Graham File used to be a whizz on KR1's.

[rigga]

Tango13 said:

dibblecorse said:

Clive Padgett is another, not as focussed but has built and run multiple 2 stroke race bikes.

Stan Stephens was a legend where I grew up in SE London

Iirc Clive Padgett was the only person to get a win with an RG500 in F1.

Also, I recall Padgetts were so highly regarded by Honda, they were the only people outside of Japan, who could secure special kit parts for their race bikes.

[Rob 131 Sport]

Whilst I get the basics of tuning, increased port sizes, forced induction, change of carb jetting etc, if someone could provide some step by step detail on how a KR1S was tuned.

[Steve Bass]

Rob 131 Sport said:

Whilst I get the basics of tuning, increased port sizes, forced induction, change of carb jetting etc, if someone could provide some step by step detail on how a KR1S was tuned.

Like any other 2 stroke.

Porting and port timing, head and base gaskets, minimising pumping losses, bigger carbs, less restricted airbox, decent expansion chambers.....

[Tango13]

Steve Bass said:

Rob 131 Sport said:

Whilst I get the basics of tuning, increased port sizes, forced induction, change of carb jetting etc, if someone could provide some step by step detail on how a KR1S was tuned.

Like any other 2 stroke.

Porting and port timing, head and base gaskets, minimising pumping losses, bigger carbs, less restricted airbox, decent expansion chambers.....

And then very carefully put together with total attention to detail!

Things like using lead solder to ensure the squish is even around the combustion chamber or shimming the spark plug to ensure the electrode is pointing in the right direction...

[Steve Bass]

Tango13 said:

Steve Bass said:

Rob 131 Sport said:

Whilst I get the basics of tuning, increased port sizes, forced induction, change of carb jetting etc, if someone could provide some step by step detail on how a KR1S was tuned.

Like any other 2 stroke.

Porting and port timing, head and base gaskets, minimising pumping losses, bigger carbs, less restricted airbox, decent expansion chambers.....

And then very carefully put together with total attention to detail!

Things like using lead solder to ensure the squish is even around the combustion chamber or shimming the spark plug to ensure the electrode is pointing in the right direction..

Indeed. It took no end of faffing to get each cylinder on my RS motor to the same squish and port height.....

[ddom]

BroadsRS6 said:

Stan Stephens. Beeline Racing. Terry Beckett. Nigel Porter (Sondel Sport). Granby Yamaha.

This was more dad's era than mine but Stan nevertheless put me onto someone who tuned my current little Cagiva.
At 76 Stan is still quite active though with 'things 2-stroke'!

Stan, fell out with him, never rated his work for regular customers, shafted me on a 350 build. It was supposed to be S3 but was weak. Turns out it wasn't honed properly. Bob Farnham sorted it, and also cleaned up the ports, made a huge difference. Best for me was Graham File, a true gent. His kit copy on my old TZ was absolutely brilliant, made a 96 bike able to match some of the fast lads on mega bucks A Kit stuff. I'll dig out the pictures, made Stan look very ropey.

[LukeBrown66]

ddom this is often the case with tuners in all walks of life, they have their special customers who they spend hours with, and often run of the mill paying guys get short shrift, happens with cars aswell as you might imagine.

[Steve Bass]

Also, 2T tuning is often a game of compromises.

You can chase outright peak power but often at the cost of losing midrange making the motor 'feel' fast when it comes on the pipe but dog slow when it's not. In the real world, especially on the road, this can often be slower than a less powerful engine but one that has a better spread of power. Especially relevant with non power valve equipped motors....
Carbs for example... whilst a 35mm carb will support higher peak bhp than a 28mm, it's often at the cost of lower gas velocity out of the powerband making the bike slower. The 28 gives better throttle response and performance across the rpm range but sacrifice absolute peak bhp.
Different expansion pipes with different dimensions affect the power band differently. Long tapered primaries with a longer, narrower belly, vs shorter primary with a fatter belly all produce different power characteristics....

So decent tuning comes down to the owners particular wants and wishes. Decent performance or absolute peak power bragging rights.....

Edited by Steve Bass on Friday 11th June 16:01

[graham22]

J__Wood said:

I had a Stan Stephens X7 back in the early/mid 80s.
Used it for hill climbs and twisty sprints, peaky little blighter.
Always made Hartland Quay/Point just after the start where a low wall keeps you totally safe from the drop off the cliff massive fun as its headlight searched out the sky.

Never worried about the cliff, the first blind right bend before tge paddock was the challenge.

Was your X7 tge one with both pipes exiting I the same side - or something tells me that might have been Barry Gartsides??