Race chassis

[dark art]

The NS-1 has a steel frame, as someone has mentioned, and the rear suspension has no linkage, so is not progressive. The spring is progressive-wound, but that's not the same thing. It's also quite long with a wheelbase of 1285 - 1315 depending on chain adjustment.
And yes, they are readily available in Japan, if you're very rich. They're highly sought-after.
I have an old one, and it will be my next bucket project, with quite a few mods. I use those same wheels on my NS50F and NS90F buckets, BTW, and although they are pretty much the same design as RS125 wheels, they weigh a ton. Roughly.

Mine is a Spain assembled model and is around 1350 or 1360 if memory doesn´t fail, with rear axle on center adjustement. The whole bike is heavy, around 95kg all stock except the pipe and lack or mirrors, I believe they can be made to wheigh lower 70´s with some work, including custom sub-frame.
A list of parts wheights for those interested:
front wheel w/o disc 4.3 kg
back wheel w/o disc and sprocket 4.6 kg
swing arm 4.3 kg
rear suspension unit ~255mm 1.9 kg
bare frame including welded subframe and rear footstands 14kg.

They are readily available in Spain as nsr75rr and Portugal as nsr 50rr, quite cheap, altough euro conversion and transportation may be difficult for New Zealand.

The bike feel is on the very stable side, good for road, not so good for short tracks and the rear suspension is quite bad. Fitting a good quality damper and change the unit upper mount for more inclination and higher rising rate shouldn´t be hard.

[husaberg]

The NS-1 has a steel frame, as someone has mentioned, and the rear suspension has no linkage, so is not progressive. The spring is progressive-wound, but that's not the same thing. It's also quite long with a wheelbase of 1285 - 1315 depending on chain adjustment.
And yes, they are readily available in Japan, if you're very rich. They're highly sought-after.
I have an old one, and it will be my next bucket project, with quite a few mods. I use those same wheels on my NS50F and NS90F buckets, BTW, and although they are pretty much the same design as RS125 wheels, they weigh a ton. Roughly.

Mine is a Spain assembled model and is around 1350 or 1360 if memory doesn´t fail, with rear axle on center adjustement. The whole bike is heavy, around 95kg all stock except the pipe and lack or mirrors, I believe they can be made to wheigh lower 70´s with some work, including custom sub-frame.
A list of parts wheights for those interested:
front wheel w/o disc 4.3 kg
back wheel w/o disc and sprocket 4.6 kg
swing arm 4.3 kg
rear suspension unit ~255mm 1.9 kg
bare frame including welded subframe and rear footstands 14kg.

They are readily available in Spain as nsr75rr and Portugal as nsr 50rr, quite cheap, altough euro conversion and transportation may be difficult for New Zealand.

The bike feel is on the very stable side, good for road, not so good for short tracks and the rear suspension is quite bad. Fitting a good quality damper and change the unit upper mount for more inclination and higher rising rate shouldn´t be hard.

The Moriwoki MH 80 uses the NS1 frame.
http://micapeak.com/ysr/mh.html

It was brought up earlier in the thread somewhere.

[Frits Overmars]

Mine is a Spain assembled model and is around 1350 or 1360 if memory doesn´t fail.
The whole bike is heavy... I believe they can be made to weigh lower 70´s with some work

'some work' as in removing the engine and wheels? .

The bike feel is on the very stable side.....

I'll bet it is, with a wheelbase slightly longer than the bike below.

[dark art]

The Moriwoki MH 80 uses the NS1 frame.

I remember read about those bikes a few years ago and one of the bigger problems was vibration, even with the cr80 engine rubber mounted.

In bike´s defence, the wheelbase is more around 1300 than 1360 like I stated on previous post, this time i did measured, not from memery

There seems to be two versions of NS1 frames



Mine is dual seat version, would love to get a single seat, though

Back to real racing frame stuff

[Michael Moore]

For anyone who might find it interesting

https://patentimages.storage.googlea.../US4139072.pdf

is the US patent document for Tony Dawson's "Scitsu" bolted-up plate frame.

cheers,
Michael

[husaberg]

For anyone who might find it interesting

https://patentimages.storage.googlea.../US4139072.pdf

is the US patent document for Tony Dawson's "Scitsu" bolted-up plate frame.

cheers,
Michael

Thanks Michael, that frame design is featured the second pic in this thread.
Great to see some further info.
http://www.kiwibiker.co.nz/forums/sh...post1130221028

I just thought I would post these pictures of a couple of bikes I raced back when I was faster.
The Scitsu in the picture was not my one but I did ride it a few times, it is 2 aluminium plates bolted together with aluminium spacers in between, this one had a Kawasaki bottom end with an RG500 pot on it, my one had a Rotax in it and is owned at this time by Neil Hodsons dad, I know this as I got a request for some original photo's so he could restore it. The handling on the Scitsu was a little problematic at first with the front end tending to chatter through fast turns, this was resolved by altering the angle on the rear suspension. The bike was a little on the heavy side and there was talk of making one out of Honey comb but I don't think this ever happened. Tony Dawson and Nick Carpenter were the builders, Tony was also the Astrolite man I think.

Tony Dawson wheel stuff is here
http://www.kiwibiker.co.nz/forums/sh...post1130221967

I had this Dave brought them up on a previous thread they belong here more then the 2 stroke thread.

interesting stuff bellow the breasts as well 3 vs 5 spokes alloy vs carbon fibre why the original Astralights were stopped, solid vs spoked etc

[Michael Moore]

I'd be interested to learn what thickness plate and fastener sizes were used on the Kawasaki Scitsu. I've been interested in the concept since it came out.

I gathered up a bunch of photos of different bikes with plate and/or sheet frames and put them in a folder on my website:

http://www.eurospares.com/graphics/c...OrSheetFrames/

Scitsu, Foale (both Tony and his son Tom), Fior, Segale honeycomb, Tesi, Offenstadt, etc. The frames are Scitsu style, full monocoque, large fuel-bearing side spars, and even plywood monocoques.

cheers,
Michael

[Grumph]

Thanks for linking that Michael. Performance Bike mag, UK, did a write up on a readers special which used what was probably a Dawson built frame for a TZ.
It ran an LC engine and was road legal. I'll see if I can find the copy I have here and send it to Husa to scan and post.

Having built several boats, a sheet frame using ply has great appeal.

[husaberg]

I'd be interested to learn what thickness plate and fastener sizes were used on the Kawasaki Scitsu. I've been interested in the concept since it came out.

I gathered up a bunch of photos of different bikes with plate and/or sheet frames and put them in a folder on my website:

http://www.eurospares.com/graphics/c...OrSheetFrames/

Scitsu, Foale (both Tony and his son Tom), Fior, Segale honeycomb, Tesi, Offenstadt, etc. The frames are Scitsu style, full monocoque, large fuel-bearing side spars, and even plywood monocoques.

cheers,
Michael

Michael there is a few others on this forum chuck-em in there as well.

[Michael Moore]

Are they all in this thread or scattered around? I think I'm current on "I'd better save that photo" operations for this thread but I don't know which others might be likely suspects to have chassis photos. The photos I put in that folder are a subset of what I have, for example there are a number of other monocoque RR bikes, but I was mainly looking for a few representative photos to compare to the Scitsu-ish photos.

cheers,
Michael

[husaberg]

Are they all in this thread or scattered around? I think I'm current on "I'd better save that photo" operations for this thread but I don't know which others might be likely suspects to have chassis photos. The photos I put in that folder are a subset of what I have, for example there are a number of other monocoque RR bikes, but I was mainly looking for a few representative photos to compare to the Scitsu-ish photos.

cheers,
Michael

Yes Use the thread tools (up the top left) to search the pics.
I have had a good look arround your site. some of what i added to this thread are even from there.
But there are many others you don't have on your page.
Remember click three tmes on Image

[Michael Moore]

I wasn't aware there was an image search like that, it is very convenient. I ran it on the entire buckets forum and I'm 25% of the way through all of them.

I didn't see any photos of the 50cc Jawa Gimo so I've attached some.

cheers,
Michael

[F5 Dave]

Wow. They, certainly didn't care much for front end traction did they?

[Grumph]

Wow. They, certainly didn't care much for front end traction did they?

Not as bad as it looks, Dave. The "tank" is a dummy with fuel in the top tube. That front end won't be light either.
I'd pick that with rider prone, it'll be close to 50/50 weight distribution.

[F5 Dave]

The cut off tail section makes the seat look like its right back I'll grant thee.

The engine is what first grabbed my attention for positioning.