Author Topic: Montessa 250 VR  (Read 1657 times)

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Offline 2 shocks

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Montessa 250 VR
« on: December 29, 2017, 01:21:04 PM »
Would anybody know the original needle jet and needle size for a 1974 - 75 Montessa VR 250, Bing Carby

Thanks

Ken Baker

Offline Hoony

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Re: Montessa 250 VR
« Reply #1 on: December 29, 2017, 10:13:11 PM »
Contact Ross Nimmo on Facebook Ken, he's your Monty man
Long time Honda Fan, but all bike nut in general, Big Bore 2 stroke fan.    http://www.youtube.com/watch?v=XJoKP6MawYI
1985 Honda CR500RF "Big Red"
1986 Honda CR250RG
2005 KTM 300EXC "The GruntMeister" ( I love that engine)

Offline bigk

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Re: Montessa 250 VR
« Reply #2 on: December 30, 2017, 09:00:46 AM »
Contact Jared bates at Southwest Montesa, a wealth of knowledge & a real nice, helpful guy.
K

Offline cappra

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Re: Montessa 250 VR
« Reply #3 on: January 03, 2018, 06:35:35 AM »
Ken,
Bing 11500- 34mm

Main jet- 155/160
Low speed jet (pilot)- 50
Needle jet- 2.85
Needle- 46-281/46-283

Offline 2 shocks

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Re: Montessa 250 VR
« Reply #4 on: January 11, 2018, 08:25:04 AM »
thanks to hoony mick hughes and cappra problem solved

Offline Nebo

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Re: Montessa 250 VR
« Reply #5 on: January 27, 2018, 12:03:51 PM »
    Would not use this jetting with Modern Fuel.

    It will Seize.

Offline 2 shocks

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Re: Montessa 250 VR
« Reply #6 on: January 27, 2018, 09:38:50 PM »
What would you recommend ?

Offline Nebo

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Re: Montessa 250 VR
« Reply #7 on: January 29, 2018, 02:46:00 PM »
  To be Safe  . Go 165/170 main jet.

   Run BP Premium Unleaded 98 Octane. 
 
   32. 1 Mix.  Castrol TTS or Motel 800.

    NGK B9EGV  spark Plug.
   
     Timing should be 2.5/3 mm BTDC.

     Give it run and check for sound of Detonation / Pinging.

     Do a plug reading with a new Spark Plug.
     
     


Offline Slakewell

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Re: Montessa 250 VR
« Reply #8 on: January 29, 2018, 02:52:34 PM »
With no reed valve motors and Bings, You may need to modify the slide cut away to get that nice crisp off the bottom pull. 
Current bikes. KTM MC 250 77 Husky CR 360 77, Husky 82 420 Auto Bitsa XR 200 project. Dont need a pickle just need to ride my motorcickle

Offline 2 shocks

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Re: Montessa 250 VR
« Reply #9 on: January 29, 2018, 04:23:03 PM »
al
good info thanks