Author Topic: RM 125 cylinder  (Read 1674 times)

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Offline Nipper

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RM 125 cylinder
« on: November 30, 2012, 04:59:32 PM »
I have a rm 125 b cylinder that is now at 56mm this is 2mm over the original and it is not looking pretty down there.
I am thinking of getting it resleeved so as to start with a standard piston. Is this the best way to go ,or should I just look for another barrel? Any thoughts .Cheers Nipper


Offline Canam370

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Re: RM 125 cylinder
« Reply #2 on: November 30, 2012, 05:45:51 PM »
I have a 125B engine with electrics I'll part with- no piston but the bore looks OK and the bore measures 54mm. PM if interested for details.
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Re: RM 125 cylinder
« Reply #3 on: November 30, 2012, 05:53:43 PM »
I'll swoop on it if he is not interested.

Offline Lozza

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Re: RM 125 cylinder
« Reply #4 on: November 30, 2012, 07:53:12 PM »
I have a rm 125 b cylinder that is now at 56mm this is 2mm over the original and it is not looking pretty down there.
I am thinking of getting it resleeved so as to start with a standard piston. Is this the best way to go ,or should I just look for another barrel? Any thoughts .Cheers Nipper

You can Nicasil over cast iron would cost the same as the NOS cylinder.
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Offline bigk

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Re: RM 125 cylinder
« Reply #5 on: November 30, 2012, 10:34:01 PM »
Use an Elsinore piston. 56-58mm should be plenty of cylinder to bore that far.. You'll have to do something about the increased compression unless you can get some better then pump fuel.
K

Offline Bamford#69

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Re: RM 125 cylinder
« Reply #6 on: December 01, 2012, 12:42:28 PM »
Hi,
If  you use an Elsinore piston 56-58mm, remember GCR rule 12.4.5.1 page 92, Engine Capacity Tolerances, Classic Motocross 5% permitted excess (bore/engine size).
cheers

Offline firko

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Re: RM 125 cylinder
« Reply #7 on: December 01, 2012, 05:39:54 PM »
Quote
If  you use an Elsinore piston 56-58mm, remember GCR rule 12.4.5.1 page 92, Engine Capacity Tolerances, Classic Motocross 5% permitted excess (bore/engine size).
;D ;D ;D ::)
« Last Edit: December 01, 2012, 05:42:06 PM by firko »
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Offline vandy010

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Re: RM 125 cylinder
« Reply #8 on: December 01, 2012, 06:07:25 PM »
Quote
If  you use an Elsinore piston 56-58mm, remember GCR rule 12.4.5.1 page 92, Engine Capacity Tolerances, Classic Motocross 5% permitted excess (bore/engine size).
;D ;D ;D ::)
^^^
what he said ;D ;D ;D ::)
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Offline Nipper

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Re: RM 125 cylinder
« Reply #9 on: December 02, 2012, 02:03:34 PM »
Thanks guys for your input with the rm cylinder it has been great. Canam370 has come to the rescue with a spare parts motor to help fix the situation. Cheers Nipper.