Newbie question Robron Rocket Roadster

[opsman64]

Hello! New to the forum and karts in general. Recently purchased this frame as a project with my grandson ... I understand most of what you're looking at but absolutely can't understand how the rear axe attaches, any input or pictures would be much appreciated.

Thanks in advance

PMW

 

[Hellion]

Nice find. It looks like the rear axle hangers have been cut off. I can even see the place where they were welded on. Probably just some angle bracket pieces were used. Find some old Robron photos to go off of.

 

[opsman64]

Nice find. It looks like the rear axle hangers have been cut off. I can even see the place where they were welded on. Probably just some angle bracket pieces were used. Find some old Robron photos to go off of.

No welds. No holes. Maybe never never completed?

 

[Hellion]

No welds. No holes. Maybe never never completed?

That is a possibility. I heard the company was in flux for a while.
I see smooth bare metal that a previous owner may have touched with a flap disc sander, maybe

 

[Hellion]

The kart in this thread has the typical diamond shaped bearing hangers that bisect the frame, but yours could be a different type.

Robron go kart info WANTED

I picked up this little go kart last weekend. It's way to small for me, but I just couldn't pass it up. It came with a 5hp Briggs engine that I doubt was original to the kart. The guy said it runs... pfft, maybe at one time, but as soon as I took the cap off the tank, I could tell it was a LONG...

www.diygokarts.com

 

[Whitetrashrocker]

Bearing Hanger

The Bearing Hanger is a high-quality, durable hanger designed for use with bearings. It is made from sturdy materials that ensure long-lasting performance and reliability. This hanger is ideal for use in a variety of applications, including industrial equipment, machinery, and automotive parts...

www.gopowersports.com

 

[Hellion]

Looks like it could have been a “dead axle” basic model…

New here...what is this RobRon?

Here is my second kart project. It is a RobRon which has Manco aluminum split rims and a black vinyl seat cover. It had a 5 h.p. Briggs with a bad cylinder/piston which I am likely to replace with a Honda clone. I have read a little about the history of Rupp and RobRon karts and am very...

www.diygokarts.com

Which can be good. If so, I’d restore it back to OEM. The first racing karts were single wheel drive, aka dead axle.

 

[Hellion]

How much did you pay for it? Robron is sort of collector grade due to its association with the exalted Rupp.
It’s your choice if you want to butcher it, chop it up, add suspension, add a full roll cage, paint it neon green…

In fact wouldn’t you be better served with a late model buggy-kart with a full roll cage, lights, electric start, seat belts, f-n-r transaxle and so forth for your grandson? Plenty of those to be found on craigslist or FB marketplace that “ran when parked” and can be had for a song…

 

[opsman64]

With the serial number tag it was pretty easy to research the brand which automatically pulls you into the Rupp acquisition. At that point I knew I wouldn't be able to 'hurt' it. I am into 67-69 Plymouth Barracudas so I have a little background in collectables.

At this point I will hang it on a wall ... create an OEM parts list and start trying to locate everything that is missing. I will find something less collectable to build with my grandson (or do both).

I really appreciate the information. Obviously not sure how their serial number sequencing worked (all models in chronological order or?) but one of the photos you sent has a serial number 26 digits higher than the one I have so I'd think that eliminate the never finished hypothesis.

 

[Whitetrashrocker]

Lets see that A body!

 

[opsman64]

Lets see that A body!

She is not a looker ... she is a COMPLETE 1967 383 Formula S Fastback Barracuda. Great paperwork trail including a pristine build sheet!

 

[Whitetrashrocker]

'70 512 stroker.

 

[opsman64]

'70 512 stroker. View attachment 163969

Awesome brother!

 

[Hellion]

She is not a looker ... she is a COMPLETE 1967 383 Formula S Fastback Barracuda. ...

That’s okay, watching various YT channels or David Freiburger has given me new appreciation for aged mean machines that are “runners” with all their “patina” (starting to hate that word) intact. Plenty of “restorations” out there that, while well done, lack any flavor of the way they used to be. Oftentimes the new paint and new vinyl and what-not is way way way better than the materials of the time period.

'70 512 stroker. View attachment 163969

His Mopar is parked on the street, don’t let him fool you.

 

[opsman64]

Wheels & tires (TINO tires in name only)

 

[Hellion]

Wheels & tires (TINO tires in name only)

Azusa Tri-Stars. Good choice for a wheel/rim that is still in production and would be period-correct if not OEM for the kart. The six spoke “Manco” rims are only available used & where you can find them. They really need to re-pop those...

 

[Hellion]

I’m convinced your kart was a dead axle/one-wheel-peel kart. If it was a live axle kart it would have had the bearing hangers integrated into the frame (Rupp style), the live axle would pass through the midst and the kart frame would be level or parallel to the ground as a result. Adding W.T.R.’s under frame bearing hangers would alter the stance and make it “jacked up” in the back.

All this to say that the bottom two wheels in your pic are incorrect for the application. They are live axle wheels with a keyway, no bearings and won’t work.

Have no fear, a dead axle kart will run circles around a live axle kart because it can turn and there’s less rolling resistance. A live axle kart just wants to go in a straight line for the not so obvious reasons of live axle dynamics.

Edited to add: you can run “tires in name only” for quite a while because the tire's integrity depends a lot or mostly on the inner tube.

 

[opsman64]

I’m convinced your kart was a dead axle/one-wheel-peel kart. If it was a live axle kart it would have had the bearing hangers integrated into the frame (Rupp style), the live axle would pass through the midst and the kart frame would be level or parallel to the ground as a result. Adding W.T.R.’s under frame bearing hangers would alter the stance and make it “jacked up” in the back.

All this to say that the bottom two wheels in your pic are incorrect for the application. They are live axle wheels with a keyway, no bearings and won’t work.

Have no fear, a dead axle kart will run circles around a live axle kart because it can turn and there’s less rolling resistance. A live axle kart just wants to go in a straight line for the not so obvious reasons of live axle dynamics.

Edited to add: you can run “tires in name only” for quite a while because the tires integrity depends a lot or mostly on the inner tube.

So I believe I understand. The left rear wheel (sitting in the seat) would have a brake drum and chain sprocket mounted directly to the wheel. My next question is what do the rear wheels attach to ... there still needs to be some sort of axel and I can't tell from pictures how this was accomplished. What I see from pictures taken from above looks like square 1X1 tubing?

 

[Denny]

Welcome! Nice project!

 

[Hellion]

What I see from pictures taken from above looks like square 1X1 tubing?

Yes, it appears to be an axle “box” with round (often 5/8” diameter) stubs sticking out both sides, although I am not entirely sure how this was constructed in the factory. Might be a solid axle all the way through... but excess weight is the enemy.

Sometimes the axles are round tubing and sometimes fully integrated as frame members. You know, butted and welded into the rest of the frame members (on other kart brands). In one of those threads I posted, it seems Robron constructed the frame first, then the dead axle was welded to the frame.