Bet the water was flowing pretty good this year over the dam!You've read my mind, Jerry !
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Jim's Speed Twin Build
- Thread starter Jim
- Start date
Yamaha XS650 NVT Special
Yamaha Motor N.V. in Amsterdam carried out a lot of special projects as far back as the early 1970's. One of these was the commission of asking NVT (Norton Villiers Triumph) in Andover, U.K. to research for a better handling XS650.
At that time we got into contact with Mr. Bob Trigg, one of NVT's engineers and one of the men behind the well-known Norton Commando "Isolastic" engine mounting system. All the following pictures are taken at the very "rural" grounds... of NVT in Andover, U.K.
More and more old pictures are found and here you see the first proposed NVT prototype frame for the "Isolastic" type Yamaha/NVT XS650. So the XS650 lovers can start to copy it ! Sorry guys, I do not have the measurements.... !
The very first prototype machine was this one. For the Yamaha model, the exhaust downpipes were connected to the silencers with aircraft-type "flex" tubing. In the background you see Bob Trigg (he looks like he is hiding away from his concept!). Behind the bike are Mr. Matsuda, Yamaha's Product Planner and Paul Butler (now IRTA Chief), who at that time, was Product Planning Manager at Yamaha Amsterdam.
Here is young Ludy-San, looking quite serious on the bike (I rode it on the Andover circuit and it went like a dream!), together with Matsuda-San and Bob Trigg, who later-on stayed working for Yamaha as a consultant for many, many years.
Yamaha Motor N.V. in Amsterdam carried out a lot of special projects as far back as the early 1970's. One of these was the commission of asking NVT (Norton Villiers Triumph) in Andover, U.K. to research for a better handling XS650.
At that time we got into contact with Mr. Bob Trigg, one of NVT's engineers and one of the men behind the well-known Norton Commando "Isolastic" engine mounting system. All the following pictures are taken at the very "rural" grounds... of NVT in Andover, U.K.
More and more old pictures are found and here you see the first proposed NVT prototype frame for the "Isolastic" type Yamaha/NVT XS650. So the XS650 lovers can start to copy it ! Sorry guys, I do not have the measurements.... !
The very first prototype machine was this one. For the Yamaha model, the exhaust downpipes were connected to the silencers with aircraft-type "flex" tubing. In the background you see Bob Trigg (he looks like he is hiding away from his concept!). Behind the bike are Mr. Matsuda, Yamaha's Product Planner and Paul Butler (now IRTA Chief), who at that time, was Product Planning Manager at Yamaha Amsterdam.
Here is young Ludy-San, looking quite serious on the bike (I rode it on the Andover circuit and it went like a dream!), together with Matsuda-San and Bob Trigg, who later-on stayed working for Yamaha as a consultant for many, many years.
Yeah... that's pretty much the plan I had in mind. I fab'd the front mount but that's pretty much as far as I got. I've had some new ideas rattlin' around with the other marbles since then. Was actually thinkin' the other day about dustin' it off and seeing how I could make it work on this bike. One thing I don't like about my front mount is it doesn't tie the two down tubes together as rigidly as I'd like. Got an idea for that though.
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This is very cool, I can’t wait to see what you do with this!
You better get copyright on those pics afore I steal them and show em off to the Norton guyz!
That's awesome. um strike that, OUTSTANDING!
I'm saving those to my iso-ascot folder.
That's awesome. um strike that, OUTSTANDING!
I'm saving those to my iso-ascot folder.
I'm a "open source" kinda guy. Feel free to use 'em to build a better mousetrap.
Remind me, is that a Lord or Dynafocal ie aircraft engine mount?
When I made that all I had was a Hobart wire welder and an angle grinder. Now I have a plasma cutter, TIG, 20T press, lathe... a lot more cool toys. When I revisit the isolastics, Im'a start from scratch.
Never considered that.... all the vibe planes focused on the C/G.... hmmm...
Sorry, got sidetracked with the marbles.... 
Ahem.... neither. It's a mount I got from Speedway Motors.... just a generic rubber engine mount.... like 10 bucks a piece maybe?
Ahem.... neither. It's a mount I got from Speedway Motors.... just a generic rubber engine mount.... like 10 bucks a piece maybe?
Good read. Thanks Doug.
Like how you have done your front mount. Cant wait to see how you do the others. Good stuff.
Fair enough on the open source but those that will use it to lure unsuspecting people to their sites using your pics can do a lot of damage. All you need to do is a copyright and for personal use only. That way its harder for the the unscrupulous.
The late, great Tony Hall bought the Ascot TT design and produced the frames. IIRC in the mid 1990s they sold for a little north of $1,200 US, plus shipping across the pond. The NVT folks did things right; they tipped the motor forward about 15* so that the heavy OHC head was moved down and forward a tad. The result was much more linear steering. And no, testing showed no lubrication problems resulting from the change. I wanted one in a serious way, but by the time my budget permitted, Mr. Hall was gone and the frames were no longer to be had.
Yeah, I love the whole look of that modified XS650, with the motor tipped forward like that. I can only imagine how all that work would’ve transformed a humble 650!
That bike is simply gorgeous and I think Yamaha would have sold huge numbers of them if only they'd grasped that opportunity. A sad loss.
Good luck, Jim - hope you can pull it off!
Good luck, Jim - hope you can pull it off!
Thanks Cliff. I re-shimmed enough Norton's back in the day to know what I don't want to do.
I've got a titled and hacked frame that's lookin' at me with big eyes.... "pick me" it sez.
Gotta admit the forward tilt of the Ascot is appealing. Hmmm.....
Point taken.
