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ALLES RUND UM´S THEMA OLDIE-RESTAURATION => Bauteile & Co => Thema gestartet von: † Will am 11 Dezember 2010, 11:04:47

Titel: Carburettor for R25
Beitrag von: † Will am 11 Dezember 2010, 11:04:47
Hello everyone,
My R25/3 machine is fitted with an R25 engine. The carburettor body is from an R25/2 with a mixture of jets from other carburettors. Restorers  ::) ::)
My question is what should I fit for a better performance ?
A new R25 carburettor or fit the correct jets for the R25/2 body.

When I visited Uli's in Frankfurt he thought the machine was running very weak when he looked at the photo of the exhaust pipe which is very blue.
Also the machine has very little power with a max speed of about 65kph on level roads. :verlegen:
Many thanks in anticipation of your help.
Titel: Re: Carburettor for R25
Beitrag von: rolf am 11 Dezember 2010, 11:26:41
Hallo,
you have a 1/22/44?
Tell me which jets, needle etc. you use....65 kph is very (!) bad.
Rolf
Titel: Re: Carburettor for R25
Beitrag von: † Will am 11 Dezember 2010, 12:57:59
Zitat von: rolf am 11 Dezember 2010, 11:26:41
Hallo,
you have a 1/22/44?
Tell me which jets, needle etc. you use....65 kph is very (!) bad.
Rolf
Hi Rolf, thank you for your quick reply.
The body is 1/22/44.
Needle jet is 1208.
Jet needle is 921
Clip position 1
Idle jet is 45
Main jet is 100

The machine is very good condition apart from the poor performance. I have a new exhaust pipe and silencer to fit when the carburation is correct.

Regards,
Will
Titel: Re: Carburettor for R25
Beitrag von: rolf am 11 Dezember 2010, 23:25:43
First try:
idle jet 35
main jet 110

The spring, which hold the Jet needle, is it an "U" shape?...when you look on it?
Titel: Re: Carburettor for R25
Beitrag von: † Will am 11 Dezember 2010, 23:39:14
Zitat von: rolf am 11 Dezember 2010, 23:25:43
First try:
idle jet 35
main jet 110

The spring, which hold the Jet needle, is it an "U" shape?...when you look on it?
Hi Rolf,
Yes the clip is 'U' shaped.
I'll try your suggestion and change the jets.
Thanks.
Will
Titel: Re: Carburettor for R25
Beitrag von: rolf am 12 Dezember 2010, 12:43:15
And then report if the "top-speed"  ;D changed, ok?
Rolf
PS the U shaped ....so I can hope you have the right "Gasschieber".
Titel: Re: Carburettor for R25
Beitrag von: Rawost am 12 Dezember 2010, 15:57:04
Zitat von: rolf am 12 Dezember 2010, 12:43:15
"Gasschieber".

Gasschieber=Throttle Slide ?
Titel: Re: Carburettor for R25
Beitrag von: bullet am 12 Dezember 2010, 20:41:38
Zitat von: Rawost am 12 Dezember 2010, 15:57:04
Gasschieber=Throttle Slide ?

Yep.

Hans Günter