Has anyone had experience with racing the Rupp RMX 125? I have a very good condition roller waiting for a Sachs. The sachs is on the way.
Main questions I have:
Are they a strong built frame?
Are there any obvious design weaknesses?
Any chance of finding fenders for this?
Thank you for any help.
Tom B.
I've seen the aluminum chassis on the Nitro's severely bend from hard landings off of big jumps. Does the RMX have slides or boggie wheels ? I also recommend carbide runners for the skis, and Kalamazoo cleats for the track.
Good luck, and have fun.
Bob W.
Alright Bwob,
I did start out racing snowmobiles up here in Minnesota dontchaknow, and saw my share of Rupp ski-buggies but we must have a few poggers out there that tried their hand at the Rupp MX bike RMX125/Sachs 6B.
Tom,
First let's find out what the frame is made of? Anyone have a brochure for the Rupp?
Ron Carbaugh
Kerrville, Texas
I actually raced one in I believe 1973 or 74. It was a rocket ship. A few items about the bike were made cheap but overall it had a lot of potential. Oh, I won my class in that H/S. I passed a local hot shot on a TS185 Suzuki with the 175cc MX kit on it like he was backing up down a straight.
Dwight
Dwight Rudder
7 time ISDT / E medalist
8 time National Enduro Class Champion.
Does this mean we are going to see Coupe get ripped by a Rupp?
Bob Brizzee
P.S. Tom thanks for advice scrapping shocks
Ahh yes the memories start to kick in...filed under archives. We had only (1) RMX here that we saw at the mx tracks in MN.
My concerns are around the frame strength as mentioned by Ron.
Dwight did the major parts hold up ok?
I want to build another 125 so I dont keep doing 6-8 motos in one day on the same 6 Days. It would be a real waste of resources to find out I should have gone with another high breather CMF.
A Rupp is a terrible thing to waste.[:p]
Bob B,
I do have some plans to make this motor rip. As my dad used to say in his snowmobile racing days "She's either gonna GO or blow". Man I have some good stories about him!:)
TB
PS Bwob,
Humor is always welcome here. Too many websites go in a real bad direction. Usually I am that one thats in every crowd:D
Tom,
So far I haven't found any information on the frame. These bikes really had such a short life due to no dealers that I can't find anyone that raced one for a season. If the frame is good to go the main thing is to keep the engine bolts tight...sounds elementry, but this even hurt a lot of Penton riders that didn't do normal maintence. You build the bike and if the frame isn't up to par I have a Penton 125 frame, swingarm and frontend I will give you to have a home for the new engine.
Your right about humor........you need to tell the story about holding the flashlight for your Dad working on the snowmoble.
Ron Carbaugh
Kerrville, Texas
I have one of their Expresso Coffe makers, oh wait, that's Krupp.[:p]
Actually, my limited knowledge of the Marque is that checking all gussets and tube unions on the frame is a good idea. If the welds aren't done for the full run of the joint, have them welded to make a complete bead at the joint. Check the steering head welds as well.
Heck, with your speed and jumping ability, I'd put in frame supports anyways.....and a small parachute to assist in braking after you take the checkers.
Tony
hmmmmm! Braking after the checker flag?? Everybody thinks Tom takes a victory lap. The reality is it takes him that long to slow down. What is a brake?
B.B.
Tom;
Don't be mislead that the "Rupp" is even close to Penton as far as being able to take a beating. If you had problems keeping Hondaz together (which I have been told) there is no way you will have any success with the Rupp. I would opt for the later cmfs 73-75.
Have Fun!
Doug
Hey, thank you guys for the input. I am worried about the RMX frame coming into it because this bike has two existing repair welds from back in the day. Thay are near the lower front motor mounts. Small welds yet they may tell the future.
Thank you,
TB
Hey Tom and Ron, if the Rupp is really a rocket ship, how about the Rupp motor in a CMF Penton frame? Just a thought following another post about "hybrids". Good luck with your project!
Hi Tom, I just saw this bike on Mark's MX Swapmeet page. It looks like the one you're restoring. You might contact him about information:
http://www.vintagemx.us/guestbook/Rupp.jpg
Rupp 125 MX
Robert Enders Jr was kind enough to send me some photos of this uncommon bike. Robert also told me about the bike, saying
" I purchased the bike new from a dealer in Linglestown (Harrisburg), Pa in either 1971 or 1972. I can't quite remember. I had only seen 2 other RMX's while I was racing and they were both 125's from the Allentown, Pa area. Rupp built this model in both a 100cc and 125cc version. For their day they were very fast and competitive with all the major Japanese bikes of it's era. It's a shame the company went out of business shortly thereafter. I think they had the right idea when they built this thing...combine the best the world had to offer into one simple well designed motorcycle. In a pure drag race, I could eat any Elsinore, YZ or RM that tried me.
This ain't no minibike!!!
Some specs:
Model Rupp RMX 125
Engine: Sachs 125/6B; 54mm bore and stroke; 10:1 compression ratio; 21.8 HP/8,800 RPM; Capacitive Discharge (Motoplat) ignition-breakerless w/ integral lighting coil; 6 speed constant mesh transmission. Large still air volume air box with washable foam element.
Chassis: Double loop Chrome Moly tubing; 31 degree caster; overall length: 81.7"; overall width: 35"; overall height: 45"; wheel base: 54.5"; ground clearance: 9.5"; seat height: 32"; dry weight: 198 lbs.
Aluminum conical hubs w/ drum brakes; Akront alloy rims and Carlisle Aggressor tires; 3.00 x 21 on front; 3.50 x 18 on rear.
All Magura controls: levers and throttle.
Compare it to a Penton?? They sure are styled alike. The Rupp gas tank could be a sister to the Penton 6 days Enduro...same engine. I don't know...no one can seem to tell me if the Rupp design was a copy or if John Penton had something to do with it. I think both companies were on the same track when they built them. If the Rupp had a weak link it was the brakes and spokes. I ended up relacing both wheels with steel spokes and tying them with wire to keep them from breaking. Problem taken care of. Brakes still don't match the Japanese bikes (installed a compression release).
I never had the privilege to ride a Penton but I sure spent many hours on the Rupp. I must have liked, I still have it (at least today). I really hate to part with it...but I need the space in my shed for the newest projects. As you can see from the photos, I installed lights for trail riding after I (and the bike) retired from racing. Believe it or not I actually flat tracked this thing for almost 2 years. Just had to fit a 19" front wheel and a Penton down sweep expansion chamber. The bike was plenty fast, the rider wasn't near fast enough!!!
Rupp 125 MX 118 K jpeg file
Rupp 125 MX 107K jpeg file
This info was copy from //www.eurospares.com
Paul(socal)
Tom,
This answeres my question;
Chassis: Double loop Chrome Moly tubing; 31 degree caster; overall length: 81.7"; overall width: 35"; overall height: 45"; wheel base: 54.5"; ground clearance: 9.5"; seat height: 32"; dry weight: 198 lbs.
Ron Carbaugh
Kerrville, Texas
Tom,Do you know if the rupps petcocks work on the penton gas tanks?the tanks look about the same.just wondering.Thanks,Ric
ric emmal
Mick,
Thanks for that link! I think my bike is in better shape than the photo but if I know Mark, the bike is cherry now.
Rick, I will look into the petcock Q?
Pakala,
Fantastic info..now we are getting somewhere. Ron: You've got mail.
Couldn't resist reading up on this post, when I saw the Rupp reference. Never owned one myself, but there was several tearing around the old neighborhood, back in the day. Also, feel kind of a kinship, as they were produced right over in Mansfield. I've even met guys who worked in the mfg plant. Taking a big step to one side, Tony's reference to "parachute braking after the checkers" reminds me of a funny situation, which occured some years back at a GNCC held near Lisbon, Ohio. Freddie Andrews won, and after taking the checkers, came to a full stop at the scoring barrels. I was videotaping the event, and kept the camera on Fred as he confirmed his finishing position with the checker. Suddenly however, he and his bike lurched forward, so I zoomed back out and saw that two riders, fighting for position right down to the last few inches had run smack into the back of Fred's bike, and were now throwing punches at one another, while they were still on their bikes. Fred remained on his bike as well, and had turned in the saddle to observe the fracas, while officials moved in to separate the combatants. Those two guys were disqualified, as racing after the flag is a big, safety no-no, plus for displaying such unsportsmanlike conduct. It was a pretty funny scene, all things considered.
Ted Guthrie
Salem, Ohio
Ted,
One thing is for sure; there is something about having these early motorcycles that turns back the hands of time to when life was simpler. :)If only we knew. I would have had a camera in my hands at all times. I still vividly remember our #1 rider (Tom Severson) on his Monark GS wheelying through the deep whoops way ahead of 2nd place. I had super 8mm footage of it but lost it in a family move[V].
Tom B
Couldn't resist reading up on this post, when I saw the Rupp reference. Never owned one myself, but there was several tearing around the old neighborhood, back in the day. Also, feel kind of a kinship, as they were produced right over in Mansfield. I've even met guys who worked in the mfg plant. Taking a big step to one side, Tony's reference to "parachute braking after the checkers" reminds me of a funny situation, which occured some years back at a GNCC held near Lisbon, Ohio. Freddie Andrews won, and after taking the checkers, came to a full stop at the scoring barrels. I was videotaping the event, and kept the camera on Fred as he confirmed his finishing position with the checker. Suddenly however, he and his bike lurched forward, so I zoomed back out and saw that two riders, fighting for position right down to the last few inches had run smack into the back of Fred's bike, and were now throwing punches at one another, while they were still on their bikes. Fred remained on his bike as well, and had turned in the saddle to observe the fracas, while officials moved in to separate the combatants. Those two guys were disqualified, as racing after the flag is a big, safety no-no, plus for displaying such unsportsmanlike conduct. It was a pretty funny scene, all things considered.
Ted Guthrie
Salem, Ohio
Ted,
One thing is for sure; there is something about having these early motorcycles that turns back the hands of time to when life was simpler. :)If only we knew. I would have had a camera in my hands at all times. I still vividly remember our #1 rider (Tom Severson) on his Monark GS wheelying through the deep whoops way ahead of 2nd place. I had super 8mm footage of it but lost it in a family move[V].
Tom B