RD50M 2EO

[paufin]

Hello members.
Please, can anyone tell me if a mikuni vm20 will fit a 1977 yamaha rd50m 2EO?
Normally, it is fitted with a Teikei y14p.
Also, it has had an engine rebore to 60cc.
Is it possible to be rebored to 70-80cc ?
I purchased this moped / mokick from France.
It comes with pedals.
I would be grateful for any advice.
Thank you.

 

[MatTy]

Hi there,

I wouldn't exceed 16 mm size carb because 50cc or 60 cc in your case probably won't create enough vacuum for 20 mm carb. Just my 2 cents.

I went for a genuine 17 mm Mikuni many years ago combined with a 16 mm joint comp. since that was the smallest genuine Mikuni carb that was still in production back then. Today there are only 16 mm Mikuni reproductions available. But many people say they are pretty much ok.

Also I wouln't rebore a 50cc to 70 or 80cc.

I think it would be more important to get rid of those darn pedals ! :wink:

Cheers!

MatTy

 

[paufin]

Hi Mat Ty.
Thank you for the advice
I agree with you about the pesky pedals!
Maybe you can tell me where to buy this carburettor and also genuine yamaha cylinder and piston 60cc (43mm)
Thanks again friend

 

[MatTy]

G'arvo paufin,

hehe yeah... we have many complicated and partly very weird 50cc laws here in Germany but
fortunately we never had the "mandadory pedal law" here. Thank goodness!

IMO the best way would be to try to find a used genuine 16 mm Mikuni carb. The reason for that is simple. For Mikuni carbs you have good chances to find spare and fine-tuning parts. For the reproduction Mikuni carbs you will only find the jets. In your case (RD) a reproduction Mikuni would be also ok I guess since they are optimised for street models. So the chances are good that the jets directly fit your application. But if you ever need anything else than jets then you would have a problem.

But finding a genuine Mikuni will take time. In both cases I would recommend to check ebay every day. Not only ebay.ie ...also .co.uk, .com, .com.au and so on.

The same goes for the cylinder. In case of the cylinder it will be even harder to find one since 60 cc was only available in some countries. But don't ask me which ones.

I think it would be way easier to go for a 50 cc Yamaha cylinder. But take care... there were different cylinders with different HP ratings ! The good thing is, that the UK models for example tendencially had more powerful cylinders than we had here in Germany. The cylinder with 49cc-A identifier for example had about 4 HP and should run at least +40 mph on a RD.

Whatever you try to find, you will need patience. But if you find the desired part it will feel like christmas and easter on the same day !

Regards good luck! :rider:

MatTy

 

[paufin]

Hello MatTy
Once again, I thank you sincerely, for taking the time to answer my questions.
Your suggestions are very helpful.
I have been trying to get the right parts for a long time, with no success
I appreciate the advice and I will resume my search with added optimism
Kind regards and best wishes
Paufin<br /><br />-- 21.10.2017 16:28 --<br /><br />

 

[MatTy]

You're welcome! hehe

Yeah... you should search internationally. Otherwise it will take ages.

Just for example... I ordered my handle bar in California, handle bar pad in France, speedometer ring and keyfob in Thailand, fork decals in England, tyre valve caps in Australia, contact breaker assy in the Netherlands and so on. It didn't take that much time to find the parts. The semi-single seat I found in a village pretty near my home town... ...but it took 8 years !

Here in Europe it's very likely to find parts in the Netherlands since they are the #1 classic moped gearheads.

Nice RD :top:


Kind regards

MatTy

 

[paufin]

Cheers MatTy
I will follow your example and I will let you know how I fair out !

PauFin

 

[MatTy]

Good morning!

I forgot a very helpful detail. Try to find you one of those (yellow) Yamaha parts lists for your moped model. It is important that the list is for your specific model year! Otherwise you can't rely 100% that the part fits because Yamaha changed many things over the years.

Anyway, once you have the parts list, you will be able to search for parts with part numbers and not only by description. I am pretty sure that you will find way more parts if you use the part numbers.

The best is to try it both ways... first searching by desription and then again by part number.

Also it's a good idea to shorten out the part numbers.
For example:

(Head Lamp) Body Assy
353-84130-01-36

Shorten it out by only using the first two parts of the number >>> 353-84130

My expirience is that you will have way more hits while using google.

Just for general information... the first part of the number (353) is the model code, the second (84130) is the basic (part) code, the third (0) is the design code, the forth (1) is the design change code and fifth (36) is the color code.

Important! Don't generally ignore the other parts of the part numbers. Just for the search. Always check if it is the correct part !

Bye and good luck :rider:

MatTy

 

[paufin]

Good morning Sir.
There were so many different model codes relating to Europe.
I'm certain mine is 2E1 (France)
I think this is the parts list you mention:
Thanks again MatTy <br /><br />-- 22.10.2017 10:50 --<br /><br />

 

[MatTy]

Howdy!

yeah... that thingy will help you pretty much. Though you would have to become friends with french language... if that is ok !? Hehe :mrgreen:

The model codes are "just" numbers. More important is which parts are hidden behind these different codes. Especially when it comes to performance. Put the right parts together and you'll have a "gazelle" but if you randomly put the wrong parts together it will make you the ultimate snail racer. :wink:

My pleasure! rost:

See you later!

MatTy

 

[paufin]

Greetings maestro 8)
I learnt French in school,but that was over 30 years ago and it wasn't my favourite subject! !!!!
On e-bay, there is an English version available but not the same model code??
I will send you the image and see what you think.
You are a mine of information!
I think you have a lot of experience of the rd50.
According to Wikipedia, the 353 model had the best power and top speed and was known as an rd50 dx .
Perhaps this was before the restrictions came into force !
:help: Haha :x<br /><br />-- 22.10.2017 13:03 --<br /><br />Good morning Sir.
There were so many different model codes relating to Europe.
I'm certain mine is 2E1 (France)
I think this is the parts list you mention:
Thanks again MatTy

 

[MatTy]

Hey Paufin,

okies... I thought so. hehe :lol:

The model code or model year should fit. So the french list would be the better choice for you.
As you can see, to own a model from another country doesn't make things easier.

I am not really that much into RD's since I have a TY. But many things are similar or the same.

As far as I know, the RD 50 DX has a totally different cylinder that wouldn't fit onto your crank
case. Another member here told me that some days ago. If I remember right he said that the DX
cylinder has the identifier 420.

I think the most interesting 50cc cylinders for your application would be the ones with the identifiers 353, 49cc-A and 49cc-B. As already mentioned the 49cc-A was often used on UK models. So I guess that one would be to find the easiest for you in Ireland. The 353 is more powerful but I guess very hard to find.

Here in Germany the RD 50 M had the 2L4 cylinder and that one is pretty weak.

But always keep in mind that a cylinder with good top speed capabilities most likely will lack of torque! It will run well on country roads at top speed but in the city it's not so much fun. You should consider that.

I wish I knew the exact strengths and weaknesses of all those cylinders. I also try to find that out but that is not an easy task.

These fast moped models like the RD 50 DX also had to do with drivers license regulations here in Germany. If you got your license until 1981 then you had the permission to drive motorcycles up to 125 cc with your car license. If you got it in 1982 or later then you only had the permission to drive 50 cc - 50 kmh motorcycles.

Kind regards

MatTy