Two into One

[AlanJ]

Hi Guys,
Every time I go into the garage, especially as I have finished the Saxon 301(except MOT) I keep passing the spare engine in the middle of the floor and
thinking, wouldn't it be nice if that 251 was a 502 because I have a spare bike to fit it too, and it would be a very interesting project. A Saxon Tour with a 500
twin TS, not a bad thought is it? As you know I have an engineering background so that will help somewhat, and the fact that I have put my thoughts on this
forum will ensure I give it a good go. So that's what's buzzing around up top at the moment. There is the obvious problem though, I'm sure you are all with me
I only have half of the project, one engine, I need another ETZ 251 engine. It does not have to be a runner in super nick and it doesn't have to have electrics.
Obviously, I am expecting to buy this engine. Also if there is anybody reading this that has already succeeded in doing this, then please pm me.
It is my intention, as I only have a pedestal drill, to use a small 2 man engineering Co near me to do any machining and I will do my very best to document the
process as I go. By the way, it has to be a 251 not a 250 because I want the possibility to use injected oil if I can. Anyway, Guys stay safe.
wish you well Alan.

[dickl]

Have a look on Youtube "MZ 500 twin" for some ideas

[AlanJ]

Hi,
Thanks for that, one of the guys (Thomas Scott) did a write-up about how he completed his conversion in the MZ Riders Magazine, very interesting.
Stay safe Alan.

[breakwellmz]

https://www.youtube.com/watch?v=mUyMVp8lMWg

[Puffs]

Alan,
I don't want to sound negative, as offhand it sounds like an interesting idea.

But it has been done before, several times, and frankly, I personally wouldn't really have a need for a relatively wide & heavy 2T 500 twin, with just 40hp, which would be difficult to register and insure. Particularly if you consider that by making the engine much heavier, the frame is likely weak, and the suspension might leave something to be desired too. To me it sounds like a very big project with just a very dim light at the end of the tunnel, but once again, to each his own. I'd rather use that spare engine to make a sexy old school twin shock MX bike, but I appreciate that after a certain age (and that includes mine) you won't be getting much joy from using that. But that way it would probably have more value, and to me the process would be more rewarding. But that's just my view.

As a 500 twin: would you make it a 0° twin (pistons in unison) or a 180° twin? If you go ahead with it: good luck & looking forward to see your journey!

[Blurredman]

If you're a member of the MZ Rider's Club, then you'll have found an article recently about a member doing the same.

[AlanJ]

Hi Gents,
First of all, thanks for your input, honest, the number of times I have mentioned being inside the box and I have just done that very thing.
I have the engine and I'm in that box but I should have come outside and looked at all the various problems which in fact aren't anything to do with the engine.
Looking at that video, what a great job the guy did on that 502, it made me realize I did not have the right bike to add a 500 engine too, to add another
disc to the front wheel of a cast Saxon wheel would not be possible, I feel. That's just some of it, then there is the insurance as Puffs pointed out, again
I did not check up on that, stupid. Thanks guys for bringing me back to reality, I guess this is just one of those things that must stay in the head.
Stay safe Alan.

[AlanJ]

Hi Guys,
The amount of times this happens to me, I have written quite a large reply, just about to submit, and it just disappears. I will try again.
Yes M I am a member and that was a good article in the mag. Sitting here thinking about what I had previously posted, and of course your remarks, it made me
realize that if I was to continue with this project, I don't need another engine, I need another bike, an ETZ 251 complete. Now as I already have 5 bikes
(what do you need all those bikes for) I would have a hell of a time with a 6th. what I have to do, to do an engine project is to start with something big like
a basket car project and then slow it all down to maybe an engine and that doesn't seem so bad. My other half says when I go I will definitely need my
sunglasses.
Stay safe Alan.

[Guesi]

This is one way to do it.....

[AlanJ]

Hi Guesi,
Thanks for this post it's more than interesting. Am I right that it is showing a 180 degree ignition and an extension for the final drive? And if so, do
you know if the 180 is prefered over the parallel ignition? Excuse me asking but where did that sectional drw come from?
stay safe Alan.

[Guesi]

I cannot remember where I got this drawing....

Most of the guys who built such an engine used a TRABANT car crankshaft. And this crankshaft has a 180 degree .

But on this engine 2 crankshafts of an ETZ 250 were used. They made it also with 180 degrees. This might be due to vibrations.
As the 2 stroke works on every piston on top turn it is better that every 180 degree comes an ignition instead of parallel twin with 1 ignition on both cyclinders at the same time.

Here is another picture.

[breakwellmz]

Remember the Suzuki GT500 engine, wasn`t that based around one of their 250 singles (DT?)

[breakwellmz]

This is one way to do it.....

The attachment SCAN0001.JPG is no longer available

[DAVID THOMPSON]

that Suzuki GT500 was nice
bit of a gas hog and running in traffic it was bad to control the slow speed idle surge

there are still several in use in my area in good weather they are SHED Queens now
Dave

[AlanJ]

Hi Guesi,
Thanks for all the additional info. The reason I was especially interested in the sectional drawing and where it came from was because in my
early working time with Ford Motor Co I was a draughs person with the chassis group, often doing similar drawings to that one. The interesting thing with this drw is how did the two cranks join. Buy the way, thanks to the other guys input.
stay safe Alan.