Mugello 225 v4 piston

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Noplastic
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Hi all, i'm searching for a piston to match my mugello kit, but i can't find the letter grade on the barrel, i only see a number: 322 on both sides. Does anyone know to which piston that nbr corresponds?

any help appreciated.
Noplastic
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I trhink i'll buy an "A"..any suggestion about the quality? BGM? Also i ride it with a standard indian crank gp 200, should i go for longstroke? Full circle or...? Any recommendation for the best set up of Mugello v4 225 are welcomed. Thanks
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Ok so i fit a bgm piston and a bgm full circle crank 58x110. Problem: to align the exhaust port at bdc i fit a 2mm base gasket and 1 mm head gasket. The result is that the piston hits against the head when the head is fully torqued (is that normal?? :shock: ). So i added a 0,3mm (squish is now 1,6mm) and the engine spins freely, but the compression must be too high cause when started i hear a loud pinging knocking sound coming from the top end.

Is there anyone who tryed the BGM mrb piston on Mugello v4? I'm a bit confused... :roll: anyone who can help me to set the right squish/compression values? In the pix the exhaust port aligned at bdc with the 2mm and the piston at tdc

thanx
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Piston at tdc.jpg
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Piston at bdc.jpg
Piston at bdc.jpg (7.13 KiB) Viewed 4752 times
belly
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I think your problem is the BGM piston has a higher crown than the original Meteor piston. Your head may need machining to match the new piston
Noplastic
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belly wrote:I think your problem is the BGM piston has a higher crown than the original Meteor piston. Your head may need machining to match the new piston

Could be, the dome looks quite peaky to me but looking in the scooter center webpage they say that their piston fits all Piston ported kits:

http://www.scooter-center.com/product/BGM2225PA

Original cast iron barrels TV 200, SX 200, dl/GP 200
SIL Stage 4
AF Rayspeed Rapido Road/Race
Mugello
Avanti kit

:evil: :evil: :evil: :( :( :(

machine the head in which way? How much? :? :? I wonder if i can ask a refund or something...
Noplastic
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Can i fit a RT head on top the Muggy barrel to sort this out? Is there anyone here who has had both kits and can make a comparison? What wouldbe the best option in my case? Any help appreciated.
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corrado
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I would have thought all you needed to do when changing from a 107 conrod to 110 conrod was to use a 3mm base packer to bring everything back in line. That's what I did with my Mugello 225.
Noplastic
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Hi thanks for reply. 2 questions:

1) Have you ever used the BGM MRB ( or MBD) piston with a Mugello keeping the Mugello head?
2) Do you recommend a 2mm base packer to align the exhaust port + 1 mm head gasket or 3mm base packer and no head gasket? Cause some say the exhaust port aligning the piston at bdc is absolutely irrelevant plus that by fitting an head gasket there's the risk to misalign the head with the cylinder bore.

Any opinions?
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wack 63
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Just doing a Mugello 200 with 58 stroke and the exhaust and transfers are around 1 mm higher than the piston at BDC with the kit base gasket so maybe the 225 is the same from the factory ? Do you have the head that sits in the bore?
shocky
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Ive just hwd a 110 rod on a 58mm crank andused a 3mm packer and 1.2mm head gasket my piston crown sits above the exhaust port by about 1.5 mm the tuner harry barlow said its fine as it is and tbh it goes like fcuk with a 22mm jettex and scoot rs pipe picks up well from 35 mph in 4th ifi pack the barrel anymore ill lose low down grunt which was whati wanted on my brief to harry top bloke top tune and very reasonable
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