Dirt Bike History 101

[roadholder]

Trials bikes too...

[AndreasWeiss]

Originally Posted by PSchrauber

This is a cylinder from a "peewee" class sixdays bike, with 50ccm!

Here is the bike:


These bikes had around 10 - 12,5 HP, the engine runs best when above around 7.500 - 8.000 rpm.

No and never has this 50ccm engine 10-12,5hp at 7500-8000rpm.

This 50ccm Kreidler Van Veen has with the race kit 12-14hp at 13800rpm.
2 years later this kit was watercooled piston controlled an has 14,5hp.

[nachtflug]

Originally Posted by PSchrauber

Aahh, very good to know this little sometimes underrated brand has grow on you too!

we had a Puch dealer in town in the 1973 time era for a bit. He sold the blue and red 125 and 175's. I think they called the ones without the lights which were basically the MX model "Super Puch's" but that may have been an unofficial US nick name.

And they were pretty potent too.

Question on the dual carb 250's.

Were they sold as production bikes?

I thought those were factory rider bikes only.

[PSchrauber]

Originally Posted by PSchrauber

This is a cylinder from a "peewee" class sixdays bike, with 50ccm!

...

These bikes had around 10 - 12,5 HP, the engine runs best when above around 7.500 - 8.000 rpm.

Originally Posted by AndreasWeiss

No and never has this 50ccm engine 10-12,5hp at 7500-8000rpm.

This 50ccm Kreidler Van Veen has with the race kit 12-14hp at 13800rpm.
2 years later this kit was watercooled piston controlled an has 14,5hp.

...

Please Keep calm, stay cool and read more carefully without loosing the sentence.

I wrote the engine runs best when above around 7.500 -8.000 rpm. When you ride these peewee's under two/third throttel there is no power, that is what I tryed to explain. The throttle of an 50ccm is more like an on off switch than a power adjusting, the usful speed range is very small.

The technical spec's PUCH 50GS FRIGERIO:

lightweight aluminium cylinder with hardchrome coating
bore: 40mm
stroke: 39,7 mm
displacement: 49 ccm
compression 15
max. power 11 HP at 10500 rpm
carb: Bing 24 mm
ignition: breakerless transistored ignition, Motoplat 6V 35-5/18 W
weight: 76kg

The Kreidler van Veen is cool too, like the Frigerio brothers Mr. van Veen from Holland took serial German Kreidlers and made cool competition bikes of them. But he only reworked 50ccm engine and made one wankel motorcycle too using an Audi Ro 80 engine I believe.
His 50ccm engines for street races are famos, squeezing out 20 HP at 16.000 rpm out of 50ccm. His small company was not very long in service, from mid '70's to beginning '80's. The van Veen bikes, build in very low batches are mostly in attached hands in Holland and Germany.

The fame of the Kreidler van Veen is in commen more known by his street racers, that does not detract the MC version.

[PSchrauber]

Originally Posted by roadholder

Trials bikes too...

Thank's a lot as an trials rider which had his competition day's in the '80's I appreciate your picture posting a lot. Yes they made some wicked trials plonker too. IMHO the Puch trials bikes are assosiated with Walter Luft from Austria, he was an Worksbike rider for Puch too. He tuned them in weight, his personal bikes where very light.

Walter Luft today still riding on his Puch:


Interesting story together with Walter Luft:

He was too the practical brain for the KTM trials bike, in the mid 70's KTM made some trials prototypes.
Trial was booming in the mid 70's in Europe and KTM thaught they probably could make some
money with trial bikes too. So they started to develop a trials bike. KTM took Walter Luft and
Felix Krahnstöver under contract, Luft for Austria and Kranstöver for Germany.

The bike was made using the 420ccm gerarbox body and crank and was then fittet with a 250ccm airhead.
The frame and rest equipment was standard stuff from this era, Grimeca Hubs, Acront rims, Marccochi forks, ...

The bike looked cool and was competive too:


They showed teh bike too at the 1976 IFMA I believe, (not sure). But then it turned out,
-after a questionaire to their KTM dealers-,
that they would probably sell under 1000 units a year so they abandoned the development.

Here is Walter Luft on the KTM at the Scottish Six Day's:

[Thumpermeister]

Originally Posted by PSchrauber

They showed teh bike too at the 1976 IFMA I believe, (not sure). But then it turned out,
-after a questionaire to their KTM dealers-,
that they would probably sell under 1000 units a year so they abandoned the development.

Here is Walter Luft on the KTM at the Scottish Six Day's:

Nice pic. I heard of prototype KTM trials bikes but didnt know the extent of their competition. Looks like they had something viable there.

[PSchrauber]

Originally Posted by nachtflug

we had a Puch dealer in town in the 1973 time era for a bit. He sold the blue and red 125 and 175's. I think they called the ones without the lights which were basically the MX model "Super Puch's" but that may have been an unofficial US nick name.

And they were pretty potent too.

Question on the dual carb 250's.

Were they sold as production bikes?

I thought those were factory rider bikes only.

As I know they where sold to public, but Frigerio Puch bikes where never a bargain, they did always cost much more than the bikes of the other brands. The bikes where manufactured in the old way, so the production run of each model was very low.

Highest output overall was, - as mentioned already-, under 2000 units in 1980, and this means of all bikes beginning from 50 ccm up to 347 / 440 ccm MC, enduro, cross and some street bikes in one year.

There where also a 175ccm version available. Here is another 250ccm:



And another 250ccm from a different view:


They are dream bikes, so if I would probably have the money and the occasion and still know how to pull the throttle ... how knows what the futur will bring.

[nachtflug]

Originally Posted by PSchrauber

He is a great ressource for anything belonging to dirt-bikes in the past 50 years. If you want to know something about old machines or events he should have an answer when it comes to enduro or ISDN or KTM.

can you ask him this? I remember ISDT eraly 1970's a picture in a magazine of a BMW with 2 rear wheels mounted side by side. Can't seem to find anyone who even remembers it let alone a picture. I believe it was a German rider.

[ThomasVolomitz]

Many Penton motorcycles were on display yesterday as were John and Jack Penton themselves.

[PSchrauber]

Originally Posted by nachtflug

can you ask him this? I remember ISDT eraly 1970's a picture in a magazine of a BMW with 2 rear wheels mounted side by side. Can't seem to find anyone who even remembers it let alone a picture. I believe it was a German rider.

Sound's cool, a twintire back, but haven't seen such a bike yet. I will ask the dirt-bike community in Germany if they know something about it. Most of german speaking ISDT riders are members there, we will see if I hopefully can get any information.

The BMW Enduros made for competition where handmade machines by BMW for their works riders like Herbert Schek. The bikes where cool, but very heavy, they had a lot of torque and in my opinion too much power.

If you are a really tall guy and have muscles like Arnold and a lot of experience then this might be option for you. For me. - only 1,76m and 66kg in weight-, this bike would be a torture.

But they do look cool:


Herbert Schek on Scheck BMW in 2005 I beleive, (not sure), there he is 72!


Klaus Eisleb on a Schek Replica BMW 980 1978:





Xaver Rasch on Scheck BMW R90/6 1975:


Herbert Scheck with his BMW in 2001:


Klaus Kempter with Scheck BMW from 1978:


Auda Ausslar on BMW, sixdays 1973:


Auda Ausslar again, at the accerleration section, just pulled a little bit to much on the throttle:



Fredl Schranz on Schek BMW 75/5 1975:


Herbert Gletter, Schek BMW 75/5 1972:


Alexander Schek-Popp on Schek BMW 1972:


"inspired" by these 2 cylinder bigbores some riders in Germany build their own monsters based on the 650ccm Yamaha parallel twin engine:



Another one beside a BMW, they always show up in flocks:


Cool bikes, these double cylinder monsters, but perilous for Joe average, still dangerous for a good driver even today.

Could be collectable if there would been sold but ae I know this happens very very seldom, there are some replicas around, but the efforts for a replica are very high, nothing of the interna is standard, erverything is weight reduced, optimized for higher performance (power and torque).

Even when you ride a original or a very goor replica remember that still you have to carry along with you about 40kg more than with a standard bigbore 500cm singlecylinder fourstroke!

[nachtflug]

Originally Posted by PSchrauber

Sound's cool, a twintire back, but haven't seen such a bike yet. I will ask the dirt-bike community in Germany if they know something about it. Most of german speaking ISDT riders are members there, we will see if I hopefully can get any information.

thanks. I'm starting to wonder if my memory has failed but I'm SURE that it was an ISDT bike and I'm SURE it was a German rider.

I'll be shocked if someone in Germany doesn't recall it.

[A_Vasiliev]

Originally Posted by PSchrauber

This is very cool. I'd ride it around like a moped

[PSchrauber]

Originally Posted by nachtflug

thanks. I'm starting to wonder if my memory has failed but I'm SURE that it was an ISDT bike and I'm SURE it was a German rider.

I'll be shocked if someone in Germany doesn't recall it.

Here the Result:

Eingangsposting:
BMW GS mit Zwillingsreifen hinten, gab es so etwas einmal zum Anfang der siebziger Jahre?

Topic:
BMW gs with dual tires rear, gave it something once in the beginning of the seventies?

Frage:
Hallo, ich habe mal eine Frage an die Gemeinde:
Gab es einmal eine zwillngsbereifte BMW GS, also mit zwei Reifen am Hinterrad, in etwa im Zeitraum zwischen 1970 und 1980?
Ich bin mir selbst nicht so sicher und glaube es persönlich eigentlich nicht, ein Bekannter von mir meint jedoch, dass es so etwas wohl gegeben haben müsste.
Da ich mich mit den BMW Motorrädern auch nicht so genau auskenne, frage ich auf diesem Wege hier die Spezialisten im Forum.

Question:
Hello, I has times a question to the municipality:

There was once a twintire BMW GS, thus with two tires at the rear wheel, in the period between1970 and90? I am not sure and have some doubts, an acquaintance of me mean however that it probably must have given such a thing.
Since I am also not versed so exactly with BMW, I ask the specialists in the forum in this way here.

Antwort:
Bei Gespannen gab es das sicher, ich glaube bei Solo Motorrädern hab ich so ein Bild auch schon einmal gesehen , war aber auf jedenfall eine Bastelei und nix gescheites.

...

Vor allem fährst du in jeder Kurve nur auf einem Reifen nämlich dem Inneren.
Da der ja einen gewissen Abstand von der Fahrzeugmitte hat bildet sich da ein schöner Hebel für alle auftretenden Kräfte. Ich stell mir das zumindest gewöhnungsbedürftig vor....

Answer:
With sidecars there did exists some, I believed with solo motorcycles I have seen a picture once, it was however in any case a makeshift solution and nothing clever.

...

Above all doubts you drive in each curve only on the inner side of one of the two tires. The tire have a certain distance from the middle / center of the motorcycle and therefor this forms a beautiful lever for all arising forces. I could imagine that this behavior will take a long time getting used to it ...

So I hope you are pleased, there might be a picture, but it is not such a good idea to use double tires on a motorcycle. And there should exist a photo too.

As it is not real good idea the interest in this topic was very low and pic's did not show up.

Complete story in German, posted in offroadforum:
http://www.offroadforen.de/vb/showth...fang-der-70-er

À leur satisfaction !!

[roadholder]

Originally Posted by PSchrauber

The bike looked cool and was competive too:


They showed teh bike too at the 1976 IFMA I believe, (not sure). But then it turned out after a questionaire to their KTM dealers that they would probably sell under 1000 units a year so they abandoned the development.

Interesting.
No doubt the "fizzling" of the 1970's trials boom at about that time weighed into their plans. Too bad.

[PSchrauber]

Originally Posted by roadholder

Interesting.
No doubt the "fizzling" of the 1970's trials boom at about that time weighed into their plans. Too bad.

Bad that they had a trials project or bad that the bikes never saw serial production.