OzVMX Forum

Marque Remarks => Other Makes (CanAms, Coopers, etc) => Topic started by: TT on February 24, 2010, 08:11:36 am

Title: ATK history
Post by: TT on February 24, 2010, 08:11:36 am
Walter's advert got me thinking about the history of ATK and I asked a question there, but obviously I pissed him off by doing so, so I thought I'd ask here.  ::)
What was the configuration of the first ATK's? Did they start out with the Boyesen Link set up, or did that come later?
Any photos?
I don't own one and probably never will, but I just reckon it's an interesting part of moto history.  ;D
Title: Re: ATK history
Post by: Freakshow on February 24, 2010, 10:21:19 am
IS that the suspension link itself or the induction ?  or am i getting confused with what you asking.

i think the rotax donk is a very strange but very interesting set up, a differant looking motor to most and the belt drive thing has alway intregued me, shit fast on the flat track so they must be a good in power but wonder how they go in weight.

 RE the other : god forbit you ask a question or develope a thread into information, hes a cut and run, but rember IF you want " hazzlefree "you know were to go   :D
Title: Re: ATK history
Post by: TT on February 24, 2010, 11:16:46 am
I'm talking about the Boyesen Link rear suspension setup. I thought ATK were the first to use it, buy I'm not sure.
Title: Re: ATK history
Post by: firko on February 24, 2010, 12:25:26 pm
Here's an '84 model Tony. I think it's the earliest model but one and has the Horst Leitner suspension. I have a feeling the first model had twin shocks.
(http://img.villagephotos.com/p/2005-8/1062154/ATK54084.gif)
Title: Re: ATK history
Post by: LWC82PE on February 24, 2010, 12:42:11 pm
If any one has a photo of a twinshock ATK I would very much like to see it.
Title: Re: ATK history
Post by: TT on February 24, 2010, 12:43:00 pm
Thanks Mark.
Now I've seen it again, isn't that the A-Trak or Trax or something and how ATK got it's name? Designed by Horst Leitner instead of Eyvind Boyesen? sorry if the spelling's off a bit.  :-\
Am I confusing the two?  ???

From the LH side, that bike of Firko's could be mistaken for twin shock, I suppose.
Also, was the first ATK Rotax powered 4-stroke or Bombadier air cooled 2-stroke?
Title: Re: ATK history
Post by: LWC82PE on February 24, 2010, 01:01:36 pm
Isnt Bombardier a Rotax anyway, just re-badged?
Title: Re: ATK history
Post by: firko on February 24, 2010, 01:05:00 pm
OOps...I got my Belgians mixed with my Austrians.....Horst Leitner. I don't know where the Boyseen came from ???.
Title: Re: ATK history
Post by: TT on February 24, 2010, 01:21:48 pm
Sorry. It was me who introduced the Boyesen thing............ ::)
Title: Re: ATK history
Post by: paul on February 24, 2010, 01:32:32 pm
ATK
ATK is an off-road motorcycle manufacturer in Utah, USA, founded by an Austrian engineer, Horst Leitner, in 1980. The name "ATK" is the abreviation of the device which Leitner patented in order to eliminate chain torque for a better handling. The device was called Anti Tension Kettenantreib, from the German "chain drive".

Horst Leitner, the former 500GP racer, is well known as he designed the ATK 560, ATK 640, ATK 407 in the 80's and the Horst link design, considered an important suspension system, at the beginning of the 90's. The Horst Link is a set of rear pivots located on the chainstay just below and in front of the rear drop-out.

Horst sold ATK in the 90's and started AMP Research, which was the official supplier of car, truck and accessory products to original equipment manufacturers as Ford, Nissan, Mazda, Mitsubishi or Subaruso. This suspension design element was found on Horst's line of AMP bikes. In the late 90’s, the engineer sold the Horst link to Specialized Bicycles.

450 XC, one of the ATK bikes, has a 446cc engine which develops 46 HP at 11500 rpm. Released in 2006, it has fuel injection and electric start, Ohlins suspensions and off-road tires. The bike is not heavy at all, with only 242 lbs with only 2.6 gallons of fuel in the tank.

Just like its close relative, the 450XC, the MX version has a 446cc, liquid cooled, single cylinder engine which unleashes 46HP at 11500 rpm. ATK company dressed it up with Ohlins suspension, electric start and aluminium twin spare frame.

After the ATK 700 appeared a lot of trial addicted bikers considered that the XR650R from Honda is no longer the baddest dirt bike in the world. The XR650R has won every Baja 1000, 500 and San Felipe 250 it has ever entered.

In 2003, ATK purchased the remaining inventory of Cannondale Motorsports, which made it possible to add ATVs to their product line. A year later, ATK took first place in the Grand National Cross Country Championship and two Canadian National championships.

Currently, ATK is the only remaining off-road motorcycle manufacturer in the United States.
Title: Re: ATK history
Post by: LWC82PE on February 24, 2010, 01:37:52 pm
http://www.americandirtbike.com/
Title: Re: ATK history
Post by: Canam370 on February 24, 2010, 02:05:55 pm
Yep, Canam first used the Rotax 4 stroke in the Sonic in 1982. Twinshock.

The Sonic on local ebay awhile ago wasn't very flash at all and the seller had a cubic dollar reserve :(
Title: Re: ATK history
Post by: ba-02-xr on February 24, 2010, 02:33:49 pm
Currently, ATK is the only remaining off-road motorcycle manufacturer in the United States

What about Cobra motorcycles?
Title: Re: ATK history
Post by: motomaniac on February 24, 2010, 04:38:05 pm
Walter's advert got me thinking about the history of ATK and I asked a question there, but obviously I pissed him off by doing so, so I thought I'd ask here.  ::)
What was the configuration of the first ATK's? Did they start out with the Boyesen Link set up, or did that come later?
Any photos?
I don't own one and probably never will, but I just reckon it's an interesting part of moto history.  ;D

No bike has ever been manufactured with a Boyesen link ,they have only been retro fitted to various  models and tested.The biggest success was when Bob Hannah decided to use a modified RM250 at the USGP and won on it.That was 86 I think.
Title: Re: ATK history
Post by: motomaniac on February 24, 2010, 04:42:01 pm
OOps...I got my Belgians mixed with my Austrians.....Horst Leitner. I don't know where the Boyseen came from ???.

Eyvind Boyesen was born in Norway ( maybe Denmark)
Title: Re: ATK history
Post by: paul on February 24, 2010, 04:44:14 pm
http://www.bikepoint.com.au/all-bikes/private/details.aspx?Cr=0&R=3148852&keywords=&trecs=1&__Ns=p_RankSort_Int32|1||p_Make_String|0||p_Model_String|0||p_YearMade_Int32|1||p_PriceSort_Decimal|1&__sid=12700DC416BB&__Nne=15&__Qpb=true&seot=1&__N=1432 604 1430 1429 1428 4294964316&silo=1400
Title: Re: ATK history
Post by: paul on February 24, 2010, 04:47:00 pm
http://www.americandirtbike.com/newpage1.htm
Title: Re: ATK history
Post by: paul on February 24, 2010, 04:58:12 pm
some off those look realy cool .i might hunt one down my self . the plastics look yamahaish on some models
Title: Re: ATK history
Post by: cyclegod on February 24, 2010, 05:00:29 pm
some off those look realy cool .i might hunt one down my self . the plastics look yamahaish on some models

Early ones used a TT600 tank and seat, and some models used yammie fenders too
Title: Re: ATK history
Post by: Marc.com on February 24, 2010, 05:15:52 pm
Goldfields Motorcycles used to peddle them back in the day. I had 89 406 for a while, was cutting edge except for the motor which had the power characteristics of a farm tractor.  The only problem it had was a KTM 350 would wipe the floor with it. Final 250 I saw sat around for a while, was sold to Robbie Twyerold for $800 and he got it going really fast which given his background in air colled Yamaha motors and riding ability is not surprising.
Title: Re: ATK history
Post by: TT on February 24, 2010, 05:17:15 pm
Yeah, thanks fellas. I obviously got confused between the Boyesen Link and Horst's little project.......... too much red wine under the bridge I reckon..........  ::)
Title: Re: ATK history
Post by: LWC82PE on February 24, 2010, 06:03:27 pm
Tanks i do not think are TT600, all the ones ive seen looking quite a bit different but I can see similarities. Maybe someone can prove me wrong though.


Here is an article I just scanned.

It was scanned an uploaded as larger images but i think this forum automatically re-sizes the images. I think you can still just read the article but if anyone needs a larger copy you will have to email me.


(http://public.blu.livefilestore.com/y1p5lbblPIhkUSq3syx-9GsYoqW678NuSz-Q8tsl-rkIPpQcrRYHhjT72x2XtXeYFQUodUsaRoKNtRGqnTAxo1vCA/atk00150.jpg)

(http://public.blu.livefilestore.com/y1pTwWjUhI_mXljs8gWaK_zf8wVhjqaiUyZNodFmeeLVD9izErkNFS6-TbnJVG32Mc9KRZi97dTvrKryIvFrXOuPg/atk00250.jpg)

(http://public.blu.livefilestore.com/y1pSrDftSBgBiGsxc-f2yoLQK2qEs-2rXn_S0N4dRRRMRSibHt-9RrM5LZVTm_GDv-nPExpCpUOWCfRahInqIlfSA/atk00350.jpg)

(http://public.blu.livefilestore.com/y1pKbGpHVtg8-9S06HuqE007C1tandBCSDhsT5Z5d5AzrRvIFITISQHe0xb-HwZmHNmU_NWLRqSHAxBeJ_0hqEolA/atk00450.JPG)
Title: Re: ATK history
Post by: evo550 on February 24, 2010, 08:39:58 pm
The tank and seat from the first 560's are yz 490 K/L units.
I have never seen a twin shock version, the pic Firko posted was the first production version, I have an article of a pre production version, but it was still a single, linkless shock.
Not sure why Walter got upset and locked the listing. ??? ???
Title: Re: ATK history
Post by: Tim754 on February 24, 2010, 08:42:18 pm
 ATK Yep one shocker and mounted on one side of the swing arm. Who needs intricate fiddly bloody shitfull linkages!!! Brilliant!!! Sorry about the chain tensioner system and the disk brake rotor on the counter shaft........... ;)
Title: Re: ATK history
Post by: LWC82PE on February 24, 2010, 08:44:27 pm
what would the tank in my article be? The cap looks like Acerbis to me, but its a bit hard to tell with out seeing any closer. I can see the front fender is Acerbis and probably the rear too. I wonder what plastics Mainland and Richter products made for the bike?
Title: Re: ATK history
Post by: GMC on February 24, 2010, 09:36:47 pm
Drakie had one of the 250 2 strokes, must have been around late eighties?
I did some work on it for him as the pipe was touching on the plastics, the tank i think, so I had to tweak it a bit for some clearance.
He had me weld a few nuts on behind tabs for the guards etc. as everything was nuts & bolts which can be a bit a pain when working on them.
Think I tweaked a few other bits as well but can't remember now

Seemed to me that their must have been huge forces on the top idler sprocket of the chain system when under acceleration.

Didn't like the fact that the hose to the brake resevoir sat inbetween fins.

I noticed it had a few KTM parts on it. Muffler hanger bracket for one, as KTM was cast into it.


Overall I thought it wasn't a bad thing for something that sat outside the square.
I would have liked one of the 400's, interesting to read the 400 wasn't that good a motor.
Title: Re: ATK history
Post by: motomaniac on February 24, 2010, 09:41:45 pm
Hey Geoff did you ever go to see Horst at his factory in 85. Some of us did but I cant remember who.
Title: Re: ATK history
Post by: GMC on February 24, 2010, 09:57:55 pm
Can't remember visiting ATK, some of the memories are getting a bit vague though.
Seemed to do so much in those 2 months.
I think you & Trunky did a few different things to the rest of us, which is why I can't find any photo's of you from back then.
Do remember visiting DMC & Pro Circuit among others.
Remember seeing metre square boxes of pipe stampings at Pro Circuit that guys were welding together.

You have reminded me though I have a picture of an ATK in the pits at the Hangtown National.
I will have to dig it out for a closer look, I think it was a 4 stroke.

Think there was something about it too. They had to remove the counter shaft brake as the US rules said it had to have a rear brake which was interpreted that the brake had to be on the back wheel.
Title: Re: ATK history
Post by: holeshot buddy on February 24, 2010, 10:56:44 pm
i had a 96 atk 605 there are some pictures on the other website
they used ktm plastics
very trick bikes c&j frame  billet triples and brake lever
talon hubs excel rims white power front and rear
nissan brakes answer taper bars magura etc etc all standard
the motors are unreal chrome bore roller cam and rockers
the top end weighs nothing huge dellorto carb
they get 90hp out of them in the us  for flatrack
and you could get fuel injection as well back then
and the japs are only just doing it now ::)

nice bikes wish i kept mine :'(
Title: Re: ATK history
Post by: Mick D on February 25, 2010, 12:22:18 am
WHOO-UP there Boys, WHOO-UP ???
         Being a VMX site I would consider the best ATK would be the best pre-85 one. So lets not forget the best open class pre-85 ATK thumper ever made!

       
                  ATK-XR500
(http://i677.photobucket.com/albums/vv132/mc125mick/ImageDeposit_dot_com_FREE_Hostin-2.jpg?t=1267017535)
(http://i677.photobucket.com/albums/vv132/mc125mick/ImageDeposit_dot_com_FREE_Hostin-1.jpg?t=1267017686)
Title: Re: ATK history
Post by: motomaniac on February 25, 2010, 04:58:04 pm
pretty sure that this is Hannah testing the boyesen link at boyesens test track

http://www.youtube.com/watch?v=3ic1FnxhLkA&feature=related
Title: Re: ATK history
Post by: Marc.com on February 26, 2010, 12:35:16 pm
Overall I thought it wasn't a bad thing for something that sat outside the square.
I would have liked one of the 400's, interesting to read the 400 wasn't that good a motor.

not sure that Rotax motor in the 406 was a bad motor, it was just old air grinder and in a low state of trail bike tune, sort of felt like a DT400. Probably OK in early 80s but by late 80s you had some serious bikes like the KTM350 (best dirt bike ever) that made better power and went light years faster.
Title: Re: ATK history
Post by: firko on February 26, 2010, 01:25:53 pm
I've gotta differ with Marc on the 406 engine. While it was indeed down a bit on horsepower and technology compared to the Nipponese product of the era, with a bit of fiddling with the ports and an ultra lite aircraft spec rotary valve the bike turned into a formidable weapon. A mate of mine in the USA raced desert on one and won a lot of races on it. He sometimes did a wheel change and rode flat track with it too. I actually bought the bike (an '89 model) but sold it before I had a chance to ship it home (for a sweet little 100% profit to a Swedish guy). I rode the bike and compared to the CR500 that my mate had replaced it with it wasn't near as fast but it handled far better and turned like a Maico. In a 2 hour GP race (a 10k lap motocross/desert race sorta thing) the race times were within a minute of each other.
I later bought a 605 enduro model but once again, sold it before it was shipped home. I'm now thinking of a 250 electric start model from around 00-02. They're as cheap as shite and fast enough for this arthritc old pensioner.
Title: Re: ATK history
Post by: viper42 on February 27, 2010, 09:43:51 pm
Hi Firko,
Just to clarify one part of your statement, Atk(rotax) 406 engines are reed valve not Rotary valve.Certainly what you have stated is correct for the 250 model.

Viper 42
Title: Re: ATK history
Post by: crash n bern on March 01, 2010, 06:01:03 pm
Firko, I've been trying to find one of these electric start atk 250's.  Can only find kickers.
http://dirtbike.off-road.com/dirtbike/article/articleDetail.jsp?id=266067