collapse

www.dimecitycycles.com


www.restocycle.com

www.CITYLIMITMOTO.com

www.jadusmotorcycleparts.com

www.bisonmotorsports.com

www.speedmotoco.com

www.cognitomoto.com

www.townmoto.com

www.sparckmoto.com

www.Moto-Madness.com

www.pistonsociety.com

www.steeltowngarage.com

GET DTT UPDATES ON FACEBOOK AND TWITTER

Author Topic: 1972 DS7 The Row Boat  (Read 58052 times)

Offline clem

  • DTT BOTM WINNER
  • *
  • Posts: 1402
  • static fluff
Re: 1972 DS7 The Long Road
« Reply #30 on: Feb 15, 2013, 19:58:20 »
Well its friday night and the wife is going eat with her girlfriends, the kids are at the mother in laws and I've got a couple of newcastles that a bud left in the fridge. Going to be up late;)
Got these in the mail and the fiberglass material for the seat.

They don't seem like an easy fit but we'll make them work.
"After every war there are soldiers who refuse to surrender. To this day there are still thousands who cling to their 30+ year old motorcycles, thinking that the war is still on, refusing to concede that the four-strokes have won"

1972 DS7 http://www.dotheton.com/forum/index.php?topic=45886.msg505995#msg505995
1983 CB550sc bobber http://www.dotheton.com/forum/index.php?topic=30599.30

Offline Redbird

  • DTT SUPPORTER
  • *
  • DTT BOTM WINNER
  • *
  • Posts: 4262
  • Dolor est Magister Optimus
Re: 1972 DS7 The Long Road
« Reply #31 on: Feb 15, 2013, 21:30:12 »
Mine weren't too bad. Coupla added mounts is all. The shifter attaches to the rearset on mine though.

You'll want to use the brake light switch for the rearsets. And consider making the brake linkage attach to the stock pivot, instead of directly like I did. The geometry works out better in the long run ;)

I'm a little booked up this weekend and next with my son leaving. But after that, I'd be happy to take a ride down and give ya a hand.
When you are Dead, you don't know that you are Dead. It is difficult only for Others.

It is the same when you are Stupid.


Offline clem

  • DTT BOTM WINNER
  • *
  • Posts: 1402
  • static fluff
Re: 1972 DS7 The Long Road
« Reply #33 on: Feb 15, 2013, 23:25:53 »
I got the rearsets figured out. I had a brake linkage from a crf50 laying around and it worked out perfectly. I need to fab the brackets for the top bolt on the rearset. I am just going to weld it from thenrear framw rail to the middle one and tap holes in three places so that they are adjustable. They will just pivot on the lower bolt.

I will have to modify the shift lever to work on the bike by cutting the little arm that the linkage connects too and flip it up at about a 90 degree angle from the pedal. I'll also have to drill out the rearset for the shifter to mount to.

The kickstart misses the brake pedal too.
« Last Edit: Mar 13, 2013, 20:29:40 by clem »
"After every war there are soldiers who refuse to surrender. To this day there are still thousands who cling to their 30+ year old motorcycles, thinking that the war is still on, refusing to concede that the four-strokes have won"

1972 DS7 http://www.dotheton.com/forum/index.php?topic=45886.msg505995#msg505995
1983 CB550sc bobber http://www.dotheton.com/forum/index.php?topic=30599.30

Offline clem

  • DTT BOTM WINNER
  • *
  • Posts: 1402
  • static fluff
Re: 1972 DS7 The Long Road
« Reply #34 on: Feb 15, 2013, 23:31:35 »
I want to give Redbird some credit here on the rearsets, it's straight out of his build thread. Thanks Redbird I read your build a few times already, heck, I even read it on two stroke world just for fun ;) Hopefully our schedules can work out soon.
And Brad, you da man.
Man This bike is rusty.
"After every war there are soldiers who refuse to surrender. To this day there are still thousands who cling to their 30+ year old motorcycles, thinking that the war is still on, refusing to concede that the four-strokes have won"

1972 DS7 http://www.dotheton.com/forum/index.php?topic=45886.msg505995#msg505995
1983 CB550sc bobber http://www.dotheton.com/forum/index.php?topic=30599.30

Offline jpmobius

  • DTT BOTM WINNER
  • *
  • Posts: 1058
  • where does this go?
Re: 1972 DS7 The Long Road
« Reply #35 on: Feb 16, 2013, 10:32:38 »
Hi clem, really enjoying your build.  I'm signed up.  I have a real appreciation for anyone sorting out their own rear sets.  I think you have to do it yourself to appreciate that there is a lot more to it than it might seem at first.  I wanted to mention one of the problems with pull rod mechanical systems in case you haven't sorted it through.

The problem lies in the fact that, if the pull rod pivot (at the pedal belcrank) and the swing arm pivot are not coincident , the required rod length distance changes as the suspension moves through it's travel.  If the pull rod pivot is both very close to the swing arm pivot AND very close to being on a line drawn between the swing arm pivot and the brake arm/pull rod pivot, AND the swing arm rotation is small, the problem is insignificant.  Move even a little bit too far away, and the problem becomes noticeable.

The up shot is, if the above criteria is not considered, there will be oscillation in the brake pedal as the bike goes over bumps and the suspension moves.  This occurs in the factory set up, but it is so small it is not noticeable (at least by me)

You can observe this very easily.  support your motorcycle on the center stand, remove the shocks, and move the suspension through its travel.  You will see the brake lever move.  If you run a very tight pedal set up, that is the "up" pedal stop is adjusted for a low pedal and the brake rod adjustment is set for a very short "throw", it could be possible to engage the brake with large suspension deflections.  You can observe this also by clamping your pedal in one place while the suspension is at ride height, and then moving the suspension through its travel.  You will see the brake arm move.  Whether this is a problem or even dangerous depends on all the variables.

I really hate an oscillating pedal, and performance riding with one is out of the question.  I have built quite a few rear sets and if I have to keep the mechanical drum I use a cable system if I can't either keep the factory pivot or dream up a new one with very close geometry.  Cables have their own issues, but are super flexible in geometry possibilities.  Pull rod systems are really rugged and reliable, even elegant in their simplicity but you can not escape the kinematics required to make them work properly.

Keep up the good work - DS-7's are a BLAST!!

Mobius


On a long enough timeline, the survival rate for everyone drops to zero.

RD350 Yamaha build  http://www.dotheton.com/forum/index.php?topic=66498.0

Offline Redbird

  • DTT SUPPORTER
  • *
  • DTT BOTM WINNER
  • *
  • Posts: 4262
  • Dolor est Magister Optimus
Re: 1972 DS7 The Long Road
« Reply #36 on: Feb 16, 2013, 18:05:14 »
jp nailed it. That's why I mentioned using the factory pivot. When I had my linkage run with the drum lever pulling from the underside the oscilation was noticable. Barely, but noticable. I moved it to a top pull when I changed my shocks, and now it's annoying. And as jp mentioned, in deep suspension travel, it will engauge the brake. Slightly, but enough that I can feel it.
When you are Dead, you don't know that you are Dead. It is difficult only for Others.

It is the same when you are Stupid.

Offline Swagger

  • DTT SUPPORTER
  • *
  • Posts: 5513
  • Putting boot to ass since 1967!
Re: 1972 DS7 The Long Road
« Reply #37 on: Mar 06, 2013, 14:25:54 »
I like cable brakes for just that reason but......I somehow think it won't be an issue for you any longer.....nudge....nudge....
.....there's no way that little rice cooker is going 100m/h when the work need to get up to those speeds includes a big fuck off fairing shaped like a giant cock. ~Staffy

Weiner tetanus is nothing to scoff at. ~JustinLonghorn

Offline clem

  • DTT BOTM WINNER
  • *
  • Posts: 1402
  • static fluff
Re: 1972 DS7 The Long Road
« Reply #38 on: Mar 13, 2013, 20:45:23 »
Well this thing slid back to page 5 so I know that I've been slacking. So here is where I stand:

I got the brackets made for the rearsets and set them up for three positions. They wound up getting tapped to accept a bolt.

Mocked up:


I bought a front end off of a 2001 ZX-6E but I need to press the stem out and replace it with the DS7 stem. I haven't measured them out but hopefully it will fit in the new lower triple. I'm also thinking of building a press for this from some 3" channel. Any thoughts on that one?


I really had no clue how much work goes into a fiberglass seat. Three weekends and still not happy. Sanding is not my friend but I don't want a crap job when it's done so we will become very close.
"After every war there are soldiers who refuse to surrender. To this day there are still thousands who cling to their 30+ year old motorcycles, thinking that the war is still on, refusing to concede that the four-strokes have won"

1972 DS7 http://www.dotheton.com/forum/index.php?topic=45886.msg505995#msg505995
1983 CB550sc bobber http://www.dotheton.com/forum/index.php?topic=30599.30

Offline VonYinzer

  • DTT SUPPORTER
  • *
  • Posts: 18359
Re: 1972 DS7 The Long Road
« Reply #39 on: Mar 13, 2013, 20:48:48 »
Looks good fella. Keep at it.
Like a river that don't know where it's flowin'
I took a wrong turn and just kept goin'