name this one

[Marc.com]

could be replica of Franks replica, wow makes you wonder why Honda didn't do that in the  first place

[lukeb1961]

wonder why Honda didn't do that in the  first place

my guess would be patent/royalty questions. Didn't Yamaha hold the patent (ex Tilkens) at the time?

[DR]

could ask Suzuki the same question Luke but either way they all went on to built world championship winning bikes

[JohnnyO]

If it was a replica or special monoshock frame it wouldn't have the top shock mounts on it would it...

[Lozza]

Japanese are funny with patents, the Yamaha monoshock looks exactly the same as what's on a old Phil Irving designed VINCENT . I wouldn't have paid Tilkens 1 cent as he didn't invent the cantilever monoshock but only reinvented it. Like Honda and the single sided swing arm that they paid fortunes for, when the Ducati 916 emerged with a single sided arm, Honda's patent lawyers couldn't get to Ducati HQ fast enough.Claudio Castellegoni invites them down to talk about it, ushers them in, coffee and amoretto's, half way through the lawyers 'we're going to take you to the cleaners' speil, he jumps up opens the blinds and says "Look at the beautiful view from my office", just so happened there was an old 50's Guzzi with a single sided arm spoiling the view. Single sided arms appeared on lots of bikes after that.

[L.Ron.Pursang]

Tilkens offered the monoshock system to Suzuki which they tested before rejecting it. He then offered it to Yamaha and the rest is history. The photo probably comes from Suzukis test period with the system.

Lozza, Tilkens did indeed copy the triangulated swingarm idea from Vincent but that was only part of the deal. Tilkens single gas shock was a radical departure from the Vincent twin shock concept and is the meat of Tilkens invention. Kramer, Cheney and KSI are more like the Vincent idea than the Yamaha monoshock system.

[vmx42]

Hey Firko,
From memory Tilkens actually built his prototypes around the CZ platform and he used a Citroen car shock absorber.

The entire monoshock thing really wasn't that radical [much more of an evolutionary adaptation of previous systems] and required more compromises than really necessary in a great design. It took Yamaha years to really make it work, but by then it was obsolete. But it certainly gave the bikes a unique look and gave the marketing men something to talk about.

That should get the Yamaha guys typing.
VMX42

P.S. just for the record [before they string me up] my favorite Works Bike is Hannahs 0W40. Does that get me off the hook??

[L.Ron.Pursang]

Absolutely right Jeff. I've got a photo of one of the CZ prototypes here somewhere in my disorganised "other shit" photo file. I'll try and dig it out.

[Marc.com]

Tilkens single gas shock was a radical departure from the Vincent twin shock concept and is the meat of Tilkens invention. Kramer, Cheney and KSI are more like the Vincent idea than the Yamaha monoshock system.

hardly call switching it up to one shock a radical departure. Tilkens didn't invent shit that hadn't been tried before. BTW if Honda were that worried about intellectual property issues they might like to compensate Triumph for the oval piston twin conrod design in the NR750.

welcome back Firko, nice to have your rather extensive knowledge back in the house.

[L.Ron.Pursang]

Marc..It's not so much a radical departure but different enough to be seperated from the twin shock Vincent design. I agree that the monoshock wasn't any better than any of the more advanced twin shock designs but it was a step into the future (using technology from the past). Thanks, it's nice being back.

[Lozza]

Nobody paid much attention to Yamaha's patent,I can only find Hakan Andersen's 73 YZ 250 as the first monoshock , HERE Nico Bakker is making cantilever/damper in spine frames. Maybe tzeggy can post some pics of aftermarket monoshock TR/TD/TZ frames(Exactweld??) which all seemed to have monoshocks.

[L.Ron.Pursang]

Rather than posting the photo of Lucien Tilkens CZ prototype here's the link to it on........
www.mxworksbike.com/Tilkens_mono.htm

[Nathan S]

Monoshock wins because of the larger valve piston area (to put it into really simple terms). Not sure if the seperated oil/gas set-up was at all common in the pre-Yamaha-monoshock days either - but it is also another win.

We can discuss the merits and originality of the original Monoshock's execution (particularly the placement in the frame), but it was a step foward purely because it used superior technology in the shock absorber itself.

(As an aside, the geometry of KTM's PDS is broadly similar to that of most twin shock Evo bikes - despite the torsional loads it puts on the swing arm, meaning that extra weight that has to be built into the swing arm, they still chose to use one shock with a 46mm piston - just like Yamaha/Tilkeins did 25 years earlier.)

[L.Ron.Pursang]

In my opinion Horst Leitner, the developer of the KTM single sided linkless suspension was an even greater inovater than Tilkins. His ATK bikes used an almost identical suspension setup to that of the KTM back in 1985. He's a pretty smart cookie as the following shows.
http://www.motocrossactionmag.com/ME2/dirmod.asp?sid=&nm=&type=news&mod=News&mid=9A02E3B96F2A415ABC72CB5F516B4C10&tier=3&nid=DEECF290064245968723324C25A0976A

[Marc.com]

In my opinion Horst Leitner, the developer of the KTM single sided linkless suspension was an even greater innovator than Tilkins.

hmm so Horst forgot to bolt on one shock and invented counter shaft mounted front brake that work like hell, not to mention using 4 sprockets where 2 were doing the job, having been near a 406 the parts that didn't work were the rear brake and A Trak. America has a Hall of Fame for everything. BTW I think the later single sided chassis wrapped around the 604 was much under rated and a really good thing.

Sorry Firko i am not convinced about a major hall of fame worthy leap forward happening at ATK.... however it did happen.... at Hamamatsu cho when the 'Full Floater' rolled out the door and made everything that had gone before it look like a joke. Old Tanaka san in Suzuki's chassis department probably got and extra 10 000 Yen in his bonus and will never be a Hall of Famer, but Honda are still borrowing the floater for their GP bikes to this day. true rising rate and the shock being compressed from both ends....whiskers that's radical.