Topic: Back In The Day, These Were Hard To Beat!

[bill440cars]

         early 60's Jawa 250cc ISDT (International Six Day Trials). I got the chance to ride one years ago and they had some pretty good power! Of course they were heavier back then. I thought they were pretty impressive to ride myself.


     

[Bodi]

Does that have the quick-change gearbox? Looks like the owner (like most I knew) tossed out the Buck Rogers carb cover...

[bwaller]

Is that the infamous twingle, Bill??

[bill440cars]

Does that have the quick-change gearbox? Looks like the owner (like most I knew) tossed out the Buck Rogers carb cover...

          No, no quick change gearbox on those. I'll tell you this much though, they came with extras like an innertube, a bottle capable of holding a charge of compressed air  (to refill the inner tube that you might have replaced), a dual ignition system (consisting of an an extra coil, and plug with a toggle switch to go from one to the other as needed) and I know there was more, but I can't think of the rest right now. It was either this one or the motocross model that came with a set of rings and more. A feature of most all of the Jawas from 125cc to 350cc and no matter wheather the street models, ISDT or Motocross, they all came with a mechanism that allowed you to shift gears without touching the clutch lever. All you did was back off of the throttle slightly, hit the shift lever and nail the throttle again. And it WAS NOT A CENTRIFUGAL CLUTCH either. Sorry, I just wanted to make that perfectly clear.      

[bill440cars]

Is that the infamous twingle, Bill??

           No, it's not a "Twingle". All of the 125cc, 175cc & 250cc Jawas were singles and came with 2 exhaust systems until about 1960 (I say about, because I don't remember exactly which year) or so. Haven't seen anyplace to get the details on the Jawa and CZ facts so that I could refresh my memory and add to what I know about them. Anyway, about 1960 or 61', the made changes to the line and they were called CZs (instead of Jawa) and had a single exhaust system with a rather large muffler (instead of the dual system with smaller mufflers that had "Fishtail like" fins on the endcaps.

                         Only "Factory Bike" I know of that might be called a twingle was the Sears 250 (by Puch) Now, there have been bikes with 2 cylinder motors, modified to run like a single and called "Twingles".

                                     Take care, Bill

[bwaller]

Well I think Jawa had a twingle, I worked on one once, and I seem to remember it was a 250, in street form, but I'm a little foggy about those days!  Bazaare bit of engineering.

[bill440cars]

Well I think Jawa had a twingle, I worked on one once, and I seem to remember it was a 250, in street form, but I'm a little foggy about those days!  Bazaare bit of engineering.

           Never heard of one. There WAS a 350 twin but it wasn't considered a "Twingle". Are we thinking of the same definition of a "Twingle" as being a motor with all the parts of a twin, but both cylinders firing at the same time? Here's a photo of a 69' 250 Jawa and it is typical of the ones built for some time before and after 69'. Street Jawas didn't change much for years. They DID have 2 separate exhaust systems (as did the 175 & 125cc singles), but that was as far as they went.

           

[bwaller]

I may be mistaken. Whatever it was had twin pistons and a single forked con-rod.

[754]

One piston smaller than they other, connected to the main rod, part way up.

Proper name is a Split Cycle 2 Stroke.. I think it was made by Puch, they also made  the Sears Allstate bike.

DKW used a piston as a form of Supercharger on some of the 2strokes.. I think it may have been called the Roarer... loudest racebike ever from what I heard..

[bill440cars]

I may be mistaken. Whatever it was had twin pistons and a single forked con-rod.

        Hey Bryan, here's a photo I found online of a 250 Allstate (Puch) like I was talking about. Maybe that was what you are thinking about.

       

[bwaller]

Split cycle huh? I remember being 18 and working all day on sohc fours and this machine came in for an electrical problem. It was definitely a change from the routine and I quess that's why it stayed with me.

That's probably the bike Bill, thanks.

[bill440cars]

Split cycle huh? I remember being 18 and working all day on sohc fours and this machine came in for an electrical problem. It was definitely a change from the routine and I quess that's why it stayed with me.

That's probably the bike Bill, thanks.

          Yeah, I can understand why you'd remember that one. Glad I could help get your thoughts straight.

                                    Take care, Bill