Author Topic: Identify a brand new piston >> M21 piston for sale  (Read 258 times)

Offline Topdad

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Anyone identify a brand new std piston part numbe AE2364 CHEERS
" rules are made for the guidance of wise men and the blind obediance of fools"
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Online RDfella

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Re: Identify a brand new piston
« Reply #1 on: 01.08. 2019 20:48 »
Lowest piston number in my '84 AE catalogue is 8481 (Caterpillar tractor)
'49 B31, '49 M21, '53 DOT, '58 Flash, '00 Firestorm, Weslake sprint bike.

Offline muskrat

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Re: Identify a brand new piston
« Reply #2 on: 01.08. 2019 21:14 »
G'day Bob.
This is the only thing I could find. Looks like a BSA single size.
Cheers
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
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Online ironhead

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Re: Identify a brand new piston
« Reply #3 on: 01.08. 2019 23:25 »
G'day Bob.
This is the only thing I could find. Looks like a BSA single size.
Cheers

That one looks like it would be for an M21 ( bore size & compression height )
SA

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Re: Identify a brand new piston
« Reply #4 on: 02.08. 2019 09:19 »
Sure looks like M21 from figures in Hepolite book - they give part no AE12659
'49 B31, '49 M21, '53 DOT, '58 Flash, '00 Firestorm, Weslake sprint bike.

Offline Topdad

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Re: Identify a brand new piston
« Reply #5 on: 02.08. 2019 12:19 »
Thank you gentleman , any one want a piston for an M21 *whistle* *good3*
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Online duTch

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Re: Identify a brand new piston >> M21 piston for sale
« Reply #6 on: 02.08. 2019 12:38 »

 
Quote
Sure looks like M21 from figures in Hepolite book - they give part no AE12659

 Can't see how you derive that number from the number Bob gave (part numbe AE2364 )  *conf2*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
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Re: Identify a brand new piston >> M21 piston for sale
« Reply #7 on: 02.08. 2019 20:03 »
Dutch - that's the AE number for an M21 piston as catalogued.
'49 B31, '49 M21, '53 DOT, '58 Flash, '00 Firestorm, Weslake sprint bike.

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Re: Identify a brand new piston >> M21 piston for sale
« Reply #8 on: 02.08. 2019 22:04 »

 
Quote
Dutch - that's the AE number for an M21 piston as catalogued.

 Yes I gathered that, but Bob didn't mention M21- just a completely different number (part numbe AE2364 )

 nb- I really don't care- just curious
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online ironhead

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Re: Identify a brand new piston >> M21 piston for sale
« Reply #9 on: 02.08. 2019 23:47 »

 
Quote
Dutch - that's the AE number for an M21 piston as catalogued.

 Yes I gathered that, but Bob didn't mention M21- just a completely different number (part numbe AE2364 )

 nb- I really don't care- just curious

Yes you are right Dutch, The M21 is from Musky's list. The only way to ID the mysterious part now is for Bob to measure
: O/D ( piston skirt)
: Gudgeon pin Diameter
: Distance from center of pin to the top face of the piston (not any compression bump)
: total length.
Then go through the listings & see if anything matches up. ( could be off anything)
SA

Online ironhead

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Re: Identify a brand new piston
« Reply #10 on: 02.08. 2019 23:50 »
Thank you gentleman , any one want a piston for an M21 *whistle* *good3*

Bob you may need to get the verniers out & do some measuring.
SA

Offline berger

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Re: Identify a brand new piston >> M21 piston for sale
« Reply #11 on: 03.08. 2019 00:56 »
i'm sure it will fit somewhere in my old diff *countdown* *fight*

Online ironhead

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Re: Identify a brand new piston >> M21 piston for sale
« Reply #12 on: 03.08. 2019 02:19 »
Looks like there's plenty of room after getting rid of all those pesky teeth things *whistle*
SA

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Re: Identify a brand new piston >> M21 piston for sale
« Reply #13 on: 03.08. 2019 02:20 »
 
Quote
....Bob you may need to get the verniers out & do some measuring.

 And a pitcher......  *beer*  *smile*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online RDfella

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Re: Identify a brand new piston >> M21 piston for sale
« Reply #14 on: 03.08. 2019 09:49 »
Dutch - can’t see why it confused you, it was just straightforward detective work.
Someone lists a part number. I look it up in my AE catalogue and it doesn’t exist. Then Musky produces a BSA chart listing that number. Ironhead (not Bob) then suggests it’s for an M21. So I look up BSA M21 in the catalogue, cross-reference the dimensions and give the AE number listed. That’s how it was ‘derived’. Maybe the original number was superceded? (my earliest catalogue is ’73). Was only trying to be helpful, but it seems some don’t appreciate that.
'49 B31, '49 M21, '53 DOT, '58 Flash, '00 Firestorm, Weslake sprint bike.