Swingarm for 70 axle?

[1979ATC110]

Is there a swingarm that the stock ATC70 bearing carrier will fit in, or is there another swinger and carrier that the stock axle and bearings fit? TRX90 swingarm and carrier is the only one I know of so far.

[Vealmonkey]

There is no stock swingarm that I know of. You might be able to change rear bearings that would fit an atc70 axle into another swingarm, but you would have to find that out through your local bearing house. You may be better off to find what would fit a 110 axle or a newer quad axle like the trx90 though. Heck, you would probably be better off just using the whole trx90 swinger. And if you could find one, why not cut the front end off a trx90 and make a new front frame section for it?

[1979ATC110]

Thanks Pat, I thought with all the suspension 70's around in the U.S. you guys would have worked this out.
TRX90's are really rare here, haven't seen a spares swingarm available anywhere. I've seen some people with TRX90's upgrade them to TRX300 swingarms so could go that way but then they seem to be just as rare...

[Vealmonkey]

Well, there is sort of a new suspension 70 in the works, but it is coming along leisurely. I'm not sure exactly what the plans are for the swingarm. There has been talk of a more modern bearing carrier being used. I don't remember seeing any nos 70 axles for sale, so they are getting tougher to come by. We need to tap into a source of something newer, wider and more heavy duty. Heck, I've seen NOS 110 axles and have picked up a couple, but they are a little heavier duty than a 70 axle. No source for Heavy Duty 110 axles either. Availability is really forcing the hand of what people are starting to design. I have a rear swinger that was designed for a pitbike, but it is steel, but it uses a 110 rear bearing carrier. If you could copy it in aluminum, then it shouldn't be that much of a problem. It's down in the basement on one of the shelves. I don't think I ever posted a picture of it.

[1979ATC110]

I'd like to see a picture of that - I prefer them in steel. I'm thinking if I cant find a swinger to use, I'll cut the carrier out of my 70 and use that to get something welded up.
I'm going to have to use a pit bike frame as there are absolutely no A+ or PK frames this side of the pond. I want to keep the stock axle, and I can source a set of shocks easy enough so that leaves the swingarm and a set of triples.
This is my 70 at the moment, it has a CT110 engine, which with the shiny leather seat and worn foot rests makes it almost impossible to stay on :-)

http://www.vftshop.com/images/others/70.jpg

I measures the thickness of my 110 and 70 axles yesterday and was surprised to see the 70 was thicker...

Is there any reason the A-frame type swing arm setup isn't used very often? This is one of the only few I've seen

http://www.vftshop.com/images/others/Image022.jpg

[Vealmonkey]

The only problem with the steel they used for the swinger, it was just too heavy. If you want to stay light, you need to go aluminum. If you had somone to fabricate you a swingarm using steel tubing or square steel, that should be lighter, but this was basically just a piece of u shaped steel channel. The place that is working on my frame is HRE and also my buddy blue27. We just couldn't bear cutting up a perfectly good suspension 70 to put my laydown 200x engine in. I've seen the piece of chromoly to be bent. The last piece of chromoly kinked at the bend. Once the main backbone is bent, then the rest of the frame should go quickly. I'm not sure what has been decided about the swingarm though. I'll keep informed or maybe blue27 will post some pics as it progresses. I'm not in any hurry to get this done.