View Full Version : TRy this again..... ATC 70 homemade rear sususpension......... PICS!!
Dirtcrasher
01-23-2010, 10:28 PM
The lathe has been so very uncooperative lately, but today I received a wedge type tool post holder which got me re-excited! :D
I'm mocking this all up on a bad frame which someone repaired HORRIBLY..... I have a new top tube about twice the thickness so it will get a huge make-over within time.
Tomorrow I will fab up the top mount and see if any angle works. My original intent waas to use a type of shock without a bladder and the Blaster shock was #1 on my list, but they are FAR too long. The 7o needs a shock about 10 - 11"s or so.
Tomorrow will tell me much more and if I'm happy, I'll chop up my running/rolling ATC70 for this mod. We'll know by then end of the day!
Suggestions and comments are welcomed :beer, none of this stuff is easy and it takes a TON of timeto get it right. It took a long time to get where I'm at right now.
Enjoy:
http://i257.photobucket.com/albums/hh220/Dirtcrasher/101_0176.jpg
http://i257.photobucket.com/albums/hh220/Dirtcrasher/101_0177.jpg
http://i257.photobucket.com/albums/hh220/Dirtcrasher/101_0178.jpg
http://i257.photobucket.com/albums/hh220/Dirtcrasher/101_0180.jpg
I can make the drum brake work, but I want a disc brake on this puppy (hopefuul by BRAPPS). If I cannot cut my own key-way, I'll have to see what fits those splines. 200X is to dig and my spare drum is hiding from me, IT KNOWS!!!!!!!!!!!!!!!!
I'll be back at it tomorrow... I'd key it, but then I need a broach to make it all work (more$$$$$$) Wish I could mate a disc to ANYTHING that fits the drum splines??!!
Take it easy guys..................
jeffatc250r
01-23-2010, 10:36 PM
Nice! Mini-cruisin in comfort. Always seems with this kinda work you end up spending more time thinking than actually working. Whats the dia on the axle where the splines are?
Vealmonkey
01-23-2010, 10:37 PM
DC, on the old atc90 disc brake kits, all that was done was to machine and old drum down until it is flat and then it was drilled for the mounting holes but the drum hub still attached in the original way. Does that make sense? The old kits also used a cable operated go kart master cylinder assembly.
Brockey
01-23-2010, 10:48 PM
I think this is awesome. For those who dont have a suspended 70 and are crafty that is sparking ideas. Not me tho, I want one but would only ruin my 70 trying.
Keep up the good work.
Dirtcrasher
01-23-2010, 10:58 PM
Thanks VEAL!!, - and everyone else too!! Maybe when I find my drum (tomorrow - we'll see) ......lol, I can just machine it?!
Jeff, I'll measure it up tomorrow - but nothing I had fit! I bet the SX ssplines are about that size, and I have no problem chopping them up! , thats why I was looking for the tiny front 81/82 250R discs and I have PLENTY of decent calipers and the ability to make mounts.
The big deal is, is the angle decent? does the shock work AOK with this model?? I can mess with that angle tomorrow, I got tired today after 13hr's in the shop..............
Who knows........ I'm no engineer, I come from a family of them but they're no fun to be around :lol: But,all I can do is TRY! I'm pissed I can't finish the 450R rearend in time but the 350X is just so reliable that I better leave well enough alone for now............................................... ......I get too overwhekmed.
I have an idea and plan to make 83/85 200X fporks chopped down for the front end - and still safe!! :D
Thanks guys!! :)
PS - BTW, That swingarm goes up a few inches, it was late, I was tired and I couldn't get it all line up height wise. We'll do that tomorrow. Still a sharp angle on an 11" shock though (eye to eye), there is no much room to suspend these things, they bare just too small. In time, I just have to make my own frames.................
jeffatc250r
01-23-2010, 11:02 PM
Thanks VEAL!!, maybe when I find my drum......lol, I can just machine it?!
Jeff, 'll measure it up tomorrow, thats why I was looking for the tiny front 81/82 250R discs and I have PLENTY of decent calipers and the ability to make mounts.
I have an idea and plan to make 83/85 200X fporks chopped down foir the front end - and still safe!! :D
Steve, Ive got a set of mid eighties yz80 forks. They fit snug as a bug in 200x tripples and are quite a bit shorter than th X forks from what i recall. Not sure what would entail making a mount for the brake caliper, never really looked to close or thought about it. If ya want em, theyre yours.
code200k
01-23-2010, 11:30 PM
nice work D.C. if this works out you planning on doing these for some spare coin or just yourself?
KASEY
01-23-2010, 11:43 PM
thats exactly what i did on my first suspended 70,,, it never did what i wanted so i opted for a complete frame, on the disc,, there is a very simple solution,,, take a stock drum turm the weld off then press it into a stock 85 250r disc hub and weld it, BOOM done!! thats what i did on this 70,, and i used a cr80 caliper and bracket
http://i14.tinypic.com/4l71wl3.jpg
Dirtcrasher
01-24-2010, 01:16 AM
Hey guys, this will all take sometime to get squared all perfectv, and hopefulley it merely works decent!! THats all I ask!! YES, PLZ bring the forks by, we can only learn by fknfg things up! :)
Rough spline ID = 1.09"s OD + 1.15 "s - close enougt so see what fits!
I found the rear drum. The prick is shaped like a bell too!! But at 4"'s on center it's gome meat to play with . It looks like plain arse steel that I can weld another plat to to accept a disc rotor - IMHO!!
Look at the bell on this hub!!!:
http://i257.photobucket.com/albums/hh220/Dirtcrasher/101_0187.jpg
http://i257.photobucket.com/albums/hh220/Dirtcrasher/101_0190.jpg
http://i257.photobucket.com/albums/hh220/Dirtcrasher/101_0192.jpg
Thanks for all the help/thoughts/etc/etc..... !!
harryredtrike
01-24-2010, 01:29 AM
lookin good dc.im sure youll figure it out
Vealmonkey
01-24-2010, 04:04 AM
You have to machne the sides of the drum off at first then see what you have left. You can then figure out if you want to machine more of the drum off and make you a plate to fit on there or whatever you want to do. And some people do it the way kasey had done his. It just all depends on what you want to do. But there are options that aren't so hard.
blue27
01-24-2010, 02:51 PM
I did what Kasey did on mine, just machined the entire drum off and it slides right into a 250R/250x/350x hub, then weld it on. Note that the 250R hub and disc are smaller then the 250-350x stuff so that is what I would use. On the Mini Tiger I used a 350x set up (larger rotor) just cause thats what was laying around the shop.
Jason Hall
01-24-2010, 03:08 PM
I would like to make one suggestion. Running the shock all the way back at the axle carrier will make you need a VERY lightly sprung shock? You have no leverage behind the shock to make compressing It very easy. I know there Isn't alot of room, but If you ran a shorter shock as a no link, and moved It forward on the swinger It would have Lots more travel, and have quite a bit softer ride.
SWIGIN
01-24-2010, 06:27 PM
If I'm hearing you right, your saying you like the feel of that shock but it is to long?
I suppose this is a little known fact but most shock company's only make a few shock shaft lengths. My 20'' eye to eye front R PEP long travel shocks use a 3'' blocker inside to limit how far the rod extends from the shock body. You can simply machine a new aluminum spacer and give that shock whatever eye to eye measurement you want.
There is always the gheto way of rethreading the rod end and threading the mount back on but then there is no going back.
oh yeah......no pics of the tool holder?!?!?!?!
Dirtcrasher
01-17-2014, 04:03 AM
God, this just reminds me how long I've been out of the game :(
Hope your OK pat and hope to talk with you soon.
Steve
DC
Dirtcrasher
01-17-2014, 04:07 AM
I would like to make one suggestion. Running the shock all the way back at the axle carrier will make you need a VERY lightly sprung shock? You have no leverage behind the shock to make compressing It very easy. I know there Isn't alot of room, but If you ran a shorter shock as a no link, and moved It forward on the swinger It would have Lots more travel, and have quite a bit softer ride.
Thank you Jason, I just found it to be a good place. And for the use it gets, I'll learn and make another one. I always appreciate you input!!!!!
Thanks bud, I agree and I'll see if I can move the forwards a bit. Too many irons in the fire right now.
Steve
DC
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