MZ ES 250/1 1962 carburettor

[grimstone]

Hello here is another question I have and I thought is better to separate in another thread.
The mechanic who worked 15 years ago on the ES fitted a Romanian brand carb. The bike runs but with lots of smoke and since I whant to bring it close as possible to original I looked over a BVF 28,5 carb which I found for about 110 Euro in good looking exterior condition but do not know what is inside (seller says it is like new). My question now is should I go for this carb or source a Mikuni VM28-57 at 130E ? Mikuni , as I read, ar the best carbs out there.

Does someoane has any info on if this is the right one, will it take some headaches off (compared to original BVF )... etc.

I took the mikuni model over here:
https://www.motorrad-leuschner-d.de/b/mikuni-vergaser
Es250/2 or es250/1... I fo not think they changed a lot regarding engine

Any advice is gladly taken.

Thx,
Theodor

[grimstone]

Nooane???
I see some bing carbs that fit but I would love mikuni.

[Guesi]

Did you notice that all these Mikuni carbs are "push in" carbs ?
Means that the carb is pushed into the intake manifold.
Yours has to be a "push over" carb.
Means that the the carb is pushed over the intake manifold.

Here you find a NOS 28,5 carb.
https://www.guesi-motorradteile.de/inde ... 3/c/_/_/?_

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[grimstone]

Hola,
So I do not know if my current Romanian carb is the proper jetting.... I do not even know from what motorcycle it was sourced.
I just see that the bike starts ok and produces smoke, engine sound good

I think I will go for a original card or a Bing and after I will have to sorce a Mikumi and make some adaptations so it can fit ( I have some experience in these adaptations, for example I made a complete caliper on a 3d mill for my BMW F650Gs to adapt the forks from a Yamaha so.... pretty hardcore). My main question here is what jetting should I look for? What are the different numbers? Does anyoane know the diameters of the jets that I have to respect for this bike?

Crankcase seals: look good sine teh biek seems to have compression but that will be sorted when engine will go throu restoration process, as the entire bike will. I already prepare chromed rims and new spokes.

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[grimstone]

Pffff....
Tuff question than. The stock carb than. What should I look for ? for example BING 84/30/110A-01. What those numbers mean?
What is the stock BVF 28,5 have?

[grimstone]

found out. 30 is the diameter of the connnection with the intake manifold.
110 means probably the same, maybe a height...


Now I have to see what exact jets I need for the es 250/1 maybe the etz or ts 250 would be ok as a starting setup?

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[grimstone]

Guys from tkm-racing recommended this:
https://www.tkm-racing.com/artikel-12671.htm
But I have to se how I fit it.
Does someoane know if the intake manifold from ES250/2 clamp on intake manifold side will fir the ES250/1 or I will have to cut the clamp side from the ES 250/2 and weld it on the ES250/1 ?

[Guesi]

Sorry, but why don´t you take the simple way and get an original carb.
The Mikuni will not fit on your bike .
So I am out of this discussion now.
You don´t seem to read the things that are written and have it your own way.
That is no fault, but it makes no sense for me to tell you what is the simple and best solution if you don´t want to follow these opinions.
Nor Oil or carb comments do you accept.

Maybe you have to learn by your money that you spend useless...

[grimstone]

Sorry, but why don´t you take the simple way and get an original carb.
The Mikuni will not fit on your bike .
So I am out of this discussion now.
You don´t seem to read the things that are written and have it your own way.
That is no fault, but it makes no sense for me to tell you what is the simple and best solution if you don´t want to follow these opinions.
Nor Oil or carb comments do you accept.

Maybe you have to learn by your money that you spend useless...

Hola thx for the response. I am gladly taking into account any advice. My primary concern regarding BVF carburetor is the lack of spares for it and the Mikuni seems a more performant carb.
Anyway I am still analyzing the situation and that is why I am getting info from many sources. And again thx a lot for your advice and it is considered.

Regarding the oil.. I am now on GL80 APIGL4 so..... it seems that the clutch issue is not related to oil but to some wear inside because something is putting pressure on some gears there that are not disengaging when some back-force is present from the wheels

And yes my biggest defect is that I like things my way and I tend to get people mad but please don't be upset and just go on. I am what I am and at 40 year... things are very difficult to change ....

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[grimstone]

Not to the racetrack. That is destroying bikes. It will be restored and a Sunday drive mostly.

BHF vs Mikuni.... i find originals for mikuni , and of course is more precise but indeed a NOS BHF....

Tuff decision

[grimstone]

So I went all tge way for a mikuni after watching tons of vids about the internals of the mikuni. They are way better build and most of the internals are replaceble, like the valve seat. The jet can also be replaced without taking the float camber cover off. Also mikuni has 2 overflows one when the level in the chamber is too high and one in case the bike tips over, so very little chance of engine floodingTommorrow it will arrive. Also considered mikuni because of the price since it was almost the same as a NOS BVF.

Now I will have to see the how I do the fitting in the intake but I suspect I will go with a rubber connection.

Yep I know I did not listen and did things my way... hope I did not messed it up

In the tons of vids I watched I found a more precise explanation of the carb rattle: because of the play betwen the slide and the carb body when engine is running is creating pressurre pulses so at idle the rattle is more pronounced because of the slide offers more surface on whitch those pulses apply but when the slide is up the pulses do not affect it so much because of the smaller surface of the slide exposed.

I'll post pics of the carb and fitting.