Original Size for Tires?

[Inactive]

Hi!

I own an UMM ALter 2,5 build in 1986, 4-Speed-Shift.
My Tires have the size: 235/75/R15.
For this size I have permission to drive in Germany.
But the cars engine ist very noisy at top speed, maybe 5500 up/m.
And the speed meter shows me a top-speed at 150 km/H. (Maybe real 120 km/h)
Is this normal?
Is this the right size?
What about the 205 R16 Tires? - Can I drive them, too?

Thanks & Regards!
Sebastian

My Aleter is one of 3 UMM known in Germany:
UMM Alter, short wheel base, hardtop, 2.5D, 4Speed, build in 1986.
Colour: Dark Blue

 

[Pedro Bettencourt]

Hi Sebastien!

The standard size of tires for the UMM is 206R16. Most of them came out of the factory with this set. In some cases, UMM would give to the client the opportunity to choose the set, either 206R16 or 235/75/R15. There is still another size; the 750R16. This one is used mainly with offroad tires, such as military, FIRESTONE SAT or GENERAL SAG.

In conclusion, you can, or should be at least, allowed to drive with both these sets. The R15 set would be more stable, while the R16 would give top speed. If I am not correct, someone will correct me.

With best regards,

Pedro Bettencourt

Terceira - Açores

 

[Inactive]

Hi.

Ok, then there are different types of rims, too?!
My one look like yours on the foto. But they are 15 Zoll instead of 16Zoll.

Greetings!
Sebastian

My Alter is one of 3 UMM known in Germany:
UMM Alter, short wheel base, hardtop, 2.5D, 4Speed, build in 1986.
Colour: Dark Blue

 

[nunumm]

Yes... UMM uses both R15 or R16...
Here it´s possible to bye a declaration at UMM with diferent tyres sizes, and then we go with that paper to oficialize the documents and then we have permission to drive with all the tyres that UMM refer to in the document.
Coust 25€ a document with 6 diferent sizes autorizations... In my case i have 14 tyre sizes permission... the 2 original, and plus 6 and 6 more.
If you want, it´s possible for me in Portugal to bye that permission and then send it for you in a letter.
We need the chassis number, year, and name of the owner... and a copy of the documents to send by mail to the UMM.
But first see if they allow you to do that in germany, with the permit paper from UMM in Portugal.

Cumps UMMistas
Nuno

 

[Inactive]

Thanks Nuno!
I will check this. But first i have to finish the car...


My Alter is one of 3 UMM known in Germany:
UMM Alter, short wheel base, hardtop, 2.5D, 4Speed, build in 1986.
Colour: Dark Blue