Swingarm of "no gods"

[brent j]

Mark had his “swingarm of the Gods” well here’s the opposite, I’ve called it the “swingarm of No Gods”
Started with this

Then this

And ended up with this


Now for the questions/opinions

Would this swingarm be legal in pre 78?

Was it available prior to 1978 and can I provide documented proof?

Well the swingarm was available, it’s a 1976 XT500C swingarm and it’s had 4” added to it.
Consider, steel plate was available back then so were welding rods and welders.
Can I prove it existed? No, but how many of us modified swingarms and frames “back then”? I’ve never been one for photos, I probably modified 20-25 swingarms and a few less frames but can’t “prove” any of them (this is probably a blessing on some of the early efforts!) I did lengthen and brace several XT swingarms, mostly 2” but one was taken to 3”

If I turned up with this on my bike at a club meeting I wouldn’t expect too many problems but what if I turned up at the nationals? Are there any scrutineers form the Crystal Brook event or any other national who would have an opinion on this one.

[firko]

In my opinion your swingarm is totally legal Brent. Swingarms have been modified since man first raced motocross. As long as the shock mounts are still in the original place and the 9'' travel limit is followed all is kosher.

[brent j]

Thanks for the comments Firko, it will be limited to 9" when I make the shocks for it. The shock mounts on the swingarm are in the original position and so are the ones on the frame. With the extra length in the swingarm I actually have to reduce the travel of the shocks to be fitted to less than the originals.
 
The next thing it will need will be a set of YZ250/400D fork legs. The triples look the same into the late 70's, early 80's (and I've got those) and they are 38mm with an offset axle.
 
When I built the first 500 a bit over 10 years ago I aimed for pre 78 with what rules I understood at the time. It was built with 9" travel front and rear but the PE swingarm and the forks, although 38mm and 9", disqualify it as they are about 1980-81.
 
I'll build this bike pre78 legal if I can and make the other one (first one) an EVO bike with 11" front and 12" rear travel, the PE swingarm and forks fit into EVO rules.

[Marc.com]

Its got the early PDI executed in mild steel look about it  .... I like it though I would galvanize it for that post modern Deus ex Crapola industrial look. Looks a hell of a lot stronger than the original early TT swinger.

[crankpin]

I can't see the image 

[Davey Crocket]

Must be a heavy little jigger Brent

[brent j]

It does weigh a bit more than a std swingarm Davey but it won’t flex! I didn’t weight the original but I will weigh this one.
Whether I pass on the weight is a different matter though!!!!!!!!!!

I did consider weight but I was hoping to keep it simple and stay within the rules.

The way I ride the weight won’t slow me down…………………….

[lukeb1961]

once you get going with the drill and make it swiss-cheese, people will be lining up to get one :-)

[crash n bern]

once you get going with the drill and make it swiss-cheese, people will be lining up to get one :-)

I was going to say the same thing.  It needs holes.

[brent j]

You're making me think....................................

[mick25]

One from the kiwi gods brent 
Looks good should work better than the stardard jobs..
I picked up a white brothers TT500 swing up off marks swap meet today  I have a dr500 alloy swing arm 25mm shorter than the pe ones
the DR500 one runs the same size axle and swing arm bolt  its a easy hook up and makes around 1500mm wheel base to

plenty of options