Rupp Go Kart

[onionfmr]

Picked this up a couple of days ago. I've been looking for a vintage kart for a couple of years. Wife says I'm in my mid-60's going on 12 years old. I'm ok with that. Guy I bought it from thought it was a 1964 or 1965 Rupp Lancer GT. I realize the gas tank and obviously the engine aren't correct. Trying to figure out what it is. Any ideas?

Got it running today. Has some issues.

First issue is that the right front spindle arm is hitting the tire on turns, see pic. I put a straight edge on it and measured the front end. Everything appears to be equal and not bent. I'm guessing that either the spindle arm is bent, wrong wheel spacers or front tires are too wide? Any ideas. Left side tire is close, also.

Second problem is that the brake disc hub is loose on the axle. Can't find any set screws to tighten. Are these hubs pressed on the axle? Any ideas?

The third problem is that the kart hops a little on hard turns, left wheel. It is a two piece frame and the adjusters on each side are not equal. More threads showing on the adjusters on the right (opposite) side of the frame. Locking nuts were also loose. Any thoughts?

Where is a good place to get vintage Rupp parts or am I at the mercy of eBay?

Kart was surprisingly fast with the clone engine. I look forward to all comments, information and advice. Thanks

 

[itsid]

if it doesn't hit going straight it mustn't hit in turns..
if it does that's a tell tale sign of a shot bearing (wheel bearings mostly)
or bushing (knuckle on the tierod) or sometimes just missing air pressure on the tyre...

talking of the tyres.. width looks fine to me..
3.5-4" tread width on vintage style slicks is of course the best fit for a kart like that;
but the modern style slicks you have shouldn't cause such issue at all
(they're bulgier [is that a word?] but an 1/8" thicker spacer is all it needs, and again if it's not touching going straight it shouldn't touch in corners either)

can't tell for sure, but it appears to be a taper lock hub..
means the hub itself is actually two parts sliding in/out.. there should be six bolts inboard..
close to the axle.. tightening these should move the taper further in ..
but chances are the key is just worn out

'sid

 

[onionfmr]

Thanks sid for your reply. As usual, very informative! I'm going to try spacers on the front axles. No interference going straight, just rubs badly on turns.

I'll try tightening the rear disc brake hub bolts and see what happens.

I've never seen a Rupp kart with the chrome rear section. Anybody seen one?

Thanks

 

[itsid]

my bets are on the wheel bearings tbh..

chromed rear.. me neither!

'sid

PS please get rid of that chinese swear word ... that kart deserves better! (it needs a two stroke.. one as old as the kart itself!!)

 

[JTSpeedDemon]

I've always wanted to mess around with a vintage 2 stroke, for the cool factor and the epic RPMs stock. They're a bit pricey, though. Here's some listings to give you ideas.

Westbend 520: https://www.ebay.com/itm/Chrysler-W...213172?hash=item469f882fb4:g:RpUAAOSwCL9doKNA $300(auction) with free shipping

Westbend 820:https://www.ebay.com/itm/Vintage-We...550069?hash=item1ccfb0ba75:g:dwwAAOSwwWNclaiG $695 OBO, $75 shipping

McCulloch 91B1:https://www.ebay.com/itm/Mcculloch-...584372?hash=item42039edcb4:g:FE0AAOSwjU9c8bJJ $350 OBO, $62 shipping

McCulloch (CM250?):https://www.ebay.com/itm/Mcculloch-...382977?hash=item3b39a80481:g:pmsAAOSwyy5c9aaM $500, $45 shipping.

 

[Beach Bum]

The "Seller" of your Go Kart thought correct.....this ad shows the Lancer GT looks like yours, right down to the Torsion Chassis.


Is your Blue Engine possibly a modified Harbor Freight Grey Hound engine? If so, it's the predecessor to the Predator Engine Harbor Freight sells now.

Nice Go Kart you bought.

 

[Beach Bum]

Another Rupp Lancer Ad

 

[JTSpeedDemon]

Yup, it's a Rupp Lancer GT. (I meticulously compared your kart to the pics)

 

[onionfmr]

my bets are on the wheel bearings tbh..

chromed rear.. me neither!

'sid

PS please get rid of that chinese swear word ... that kart deserves better! (it needs a two stroke.. one as old as the kart itself!!)

Thanks sid - I'll let you know what I find when I get into it on the right side wheel.

A little history. Seller told me he got it from his neighbor, original owner. Neighbor raced it mid to late 1960s. Blew up the engine in 1970. Brought the kart home, pulled off the engine, put the kart in his attic and it sat there until a year ago. Lost the engine and mounting bracket. Seller built it for his kid. Kid didn't care for it. So, after a lot of talking it came home with me . Priced seemed right, based on my research and the fact that I looked at an original similar Rupp kart for more than 3 1/2 times the price I paid.

Yes, I'm starting to look for original parts for it. My original plan was to put a built clone engine on it and just have fun. However, based on how original it is turning out to be, I'm seriously thinking about putting it back to original. I don't like the Dunlop tires on it. Looking for a little taller set of vintage style tires if I can find them. I want to sort the issues that I'm having before I start down any road.

---------- Post added at 03:46 PM ---------- Previous post was at 03:43 PM ----------

The "Seller" of your Go Kart thought correct.....this ad shows the Lancer GT looks like yours, right down to the Torsion Chassis.


Is your Blue Engine possibly a modified Harbor Freight Grey Hound engine? If so, it's the predecessor to the Predator Engine Harbor Freight sells now.

Nice Go Kart you bought.

Thanks for your comment on the kart.

Engine is a Central Machinery 212.

 

[JTSpeedDemon]

Central Machinery is a Greyhound engine.

 

[itsid]

Yup, it's a Rupp Lancer GT. (I meticulously compared your kart to the pics)

No... it is not!

it's no Rupp at all.. it's a pre-Rupp Lancer (1963)

At least I think so, since that'd be the single mentioning of
a chromed swing arm!

(find the typo in this ad )

And yes, I've seen the Nassau Panel of course (who couldn't?)
but those are detachables.. and more likely to be replaced than the swingarm
later in this kart's life IMHO..

The GT to my best knowledge never had a center bracing on the rear swing arm btw..
No torsion chassis not stiff rail..
(again.. not that I know at least)
Sooo 'if' it falls into the realms of Rupp Lancer naming conventions it'd be a LeMans or maybe a GrandPrix

'sid

 

[JTSpeedDemon]

*shrug*
Eh, I'm kinda used to being wrong.
This is your bi-weekly "sidslammed" moment.

Teehee, I didn't know Lancer was based in OIHO!
Yep, I found it.

 

[ezcome-ezgo]

I'm not too brite, I can't figure this one out.

 

[onionfmr]

No... it is not!

it's no Rupp at all.. it's a pre-Rupp Lancer (1963)

At least I think so, since that'd be the single mentioning of
a chromed swing arm!
View attachment 112851
(find the typo in this ad )

And yes, I've seen the Nassau Panel of course (who couldn't?)
but those are detachables.. and more likely to be replaced than the swingarm
later in this kart's life IMHO..

The GT to my best knowledge never had a center bracing on the rear swing arm btw..
No torsion chassis not stiff rail..
(again.. not that I know at least)
Sooo 'if' it falls into the realms of Rupp Lancer naming conventions it'd be a LeMans or maybe a GrandPrix

'sid

Thanks to all for your comments, especially sid. I've been doing some additional research on the kart. I've been txting with the seller, avid car guy, so, he's into vintage engine related stuff. I repeat, I'm obviously no expert on these karts. I'm trying to learn. Also, I didn't want to see a vintage piece of history like this turn into a 9 year old kid's yard kart. Seller told me that kart was originally setup for twin engines and that the center brace and bearing were there for support and to prove it. I don't know?

OK, I'm leaning to putting this kart back to original. Painful to my wallet. But, probably the right thing to do? There is a vintage go kart track approximately 10 miles form my house. Sadly, not a lot of local knowledge that I can find, yet! Maybe, I will be able. Looks like people come into town once a year for racing and that is it.

What I'm finding:

Looks like it should be running a McCulloch engine?
If single engine, engine should be mounted on right side of kart?
Needs a back of seat mounted tank?

My plan is to run a single engine. Wallet and wife can't handle dual engines! I have access from my house to a large asphalt area. Asphalt is not completely flat. However, better than conditions at local kart track. These modern tires are only 9.5" tall. Looks like originally these karts ran tires that were 10" to 11" tall. I'm thinking about going to a taller tire that is 11" or 12" tall? Narrower in the front, will help with spindle arm clearance and taller will help with ground clearance. Thoughts on this concept? I have a local guy that wants to buy the existing tires at a price that will make it a wash for me to get new tires.

Look forward to seeing comments. Thanks.

 

[itsid]

starting from the back..
ChengShin still makes vintage slicks.. (4.10 -3.5 x 5)
IMHO that's what you might want to install.
there are also NOS vintage slicks sometimes on ebay..
and vintagespeedtires.com refurbishes such and sells them IIRC

McCulloch or WestBend are likely the most popular engines back then..
if you fancy a WB820 over a Mc10 then there's nothing wrong with that.
And yes, seat mounted tank is the period correct choice to make.
(nice chromed Rupp tank replicas show up on ebay every now and again)

if you just populate the left or the right mount isn't important, whatever you feel works best for you.
some later karts even had floating tabs so you can move a single engine to the center..
that's unfortunately not the case for yours, so you have to make a decision there
essentially a narrow turn (slow) can be easier with the engine close to the outer rear wheel (to easier lift the inner)
but frankly that's only to consider if you intent to race at the limit,
with karting icons of the past it's more a friendly competition just to keep em alive and well for as long as possible.
I'd judge by the track in general (clockwise-> engine left, ccw -> engine right)
[the one you visit the most is perfectly fine to go by]
just so you have it overall in the right spot without having to iterate over all the slow turns on a track.

And for the center bracing.. sure it's to stiffen the rear
But all Rupp race karts I came across were set up to take a second engine..
and frankly that center bracing must have been a one or two year thing..
I cannot remember seeing that much on vintage rupps (two or three times so far perhaps)

'sid

 

[onionfmr]

I'm continuing on this project. Looking at Mcculloch engines. Here's a pic. of the existing clone mount. I can't find anything like this for a Mcculloch engine? Anybody seen one of these? Ideas and comments, please. Thanks.

 

[itsid]

that's not how the original enigne mounts ought to look like..
So if you want an "original" engine.. get an original mount instead

replicas show up on ebay every now and again..
(originals too.. but as for the tank....)
tank (plastic )
https://www.ebay.com/itm/Vintage-NO...nk-Rupp-Fox-McCulloch-Bug-Margay/254342838980
seen better days steel:
https://www.ebay.com/itm/vintage-bug-or-rupp-go-kart-gas-tank/274029688195

you get the idea

when in doubt contact robron
you'll most likely find all you need from him

'sid

 

[onionfmr]

that's not how the original enigne mounts ought to look like..
So if you want an "original" engine.. get an original mount instead
View attachment 112879
replicas show up on ebay every now and again..
(originals too.. but as for the tank....)
tank (plastic )
https://www.ebay.com/itm/Vintage-NO...nk-Rupp-Fox-McCulloch-Bug-Margay/254342838980
seen better days steel:
https://www.ebay.com/itm/vintage-bug-or-rupp-go-kart-gas-tank/274029688195

you get the idea

when in doubt contact robron
you'll most likely find all you need from him

'sid

Thanks again sid for your help. I sent an email to robron and I'll see if I hear back. I've sent a couple of emails out to vintage kart part sellers on eBay and I'm waiting for replies.

I want to raise the ground clearance of the kart some. From what I'm reading, tire height should be between 10" and 11". Current tires are 9.5" tall. I want to strike while the iron is hot with then guy that wants to buy the current tires. I'm contemplating running 10" tall tires on the front and 11" tall tires on the rears. Same rims. Thoughts on trying this concept.

 

[JTSpeedDemon]

1" taller in the back is what my kart runs, and I like the stance.

 

[onionfmr]

1" taller in the back is what my kart runs, and I like the stance.

Thanks for the information. I like the idea of more ground clearance and a better stance. Back in the day, we used to do that with microds that we ran.

I'm thinking of going with vintage tires, 3 1/2" wide on the front and 4 or 4 1/2" wide on the back. The narrower front tires should also help me with the tire rubbing problem on the front right spindle arm.