2mm Squish on my Imola..Running fine..Change it?

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Bofs
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Just stripped my Imola engine for a winter check-up and discovered it has a squish of 2mm!! Picked this engine up in a deal, it had 500 miles on it so I stuck it into my Series 1 and ran it all last year, it`s been faultless, pulls really well and tops out at 75mph GPS. Set-up is Imola(late version) 30mm PHBH, Fresco expansion(works really well), static electronic at 17 degrees.

It had a 0.5mm base gasket and a 0.3mm head gasket on un-matched Spanish casings. So my head tells me to lose the gaskets taking it down to 1.2mm or so (which is what I usually do with my engines) and port the casings to match the kit. My heart says put it back together as it was :roll: if it`s not broke,don`t fix it.

Anyone else run similar big squishes? And will there be an appreciable improvement in changing it?
Muffspeed....no muff too tuff
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1957 Zundapp Betta 500 Auto
1966 Motovespa Sprint 210 Polossi
1960 Lambretta Cutdown 205 Project
johnduke
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Hi, just my opinion but if its running that well ,why mess . :D Johnduke
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Bofs
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Yeh JD you`re probably right but there is always that extra horse or two to be sniffed out :twisted:
Muffspeed....no muff too tuff
Bad Samaritans SC

1957 Zundapp Betta 500 Auto
1966 Motovespa Sprint 210 Polossi
1960 Lambretta Cutdown 205 Project
Adam_Winstone
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Leave it alone
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Bofs
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Yeh maybe for the best Adam, it`s a stonking engine as is.
Muffspeed....no muff too tuff
Bad Samaritans SC

1957 Zundapp Betta 500 Auto
1966 Motovespa Sprint 210 Polossi
1960 Lambretta Cutdown 205 Project
Padge
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my imola has a drop in head so no head gasket, with no base gasket I get 1.2mm squish (which is how I run it) 1500 thrashed miles, never missed a beat (GPS'd @ 82mph) and embarrasses a lot of my mates on TS1's, rapido's, GT's, RT's etc
personally I would try and build it with no gaskets and see what its like, after all it ain't a big issue to stick some gaskets back on if you ain't happy with it is it ?
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Bofs
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What`s the rest of your set-up Padge?
Muffspeed....no muff too tuff
Bad Samaritans SC

1957 Zundapp Betta 500 Auto
1966 Motovespa Sprint 210 Polossi
1960 Lambretta Cutdown 205 Project
Padge
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186 Imola ultimate (ports cleaned up and casings matched) 30mm PHBH, franspeed supertourer, 5 plate readspead clutch, Augusto 7000 (23 static retarding to 16 degrees), mid weight flywheel , sx200 box 14/46 with GT tensioner (pull down) (5.1 final drive) my settings are in carb set up on here, pulls like a train till around 5,000-5,500 rpm then all hell breaks lose lol. I really need to get it on a dyno coz I would love to know what power its putting out as I also have a quick 210 malossi vespa putting out 21bhp and my imola leaves it standing. even my mates 24bhp TS1struggles to keep up
nellyboyo
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I`ve had 86mph on the GPS off my imola ultimate ( bloody terrifying fair play ) .
28mm keihin and NK pipe . timing set to 16 deg.
Its a pain to ride around town a bit though
Padge
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nellyboyo wrote:Its a pain to ride around town a bit though
I find exactly the opposite, smooth as anything and pulls like a train from tickover and a few people that have riden it describe it as nuts/violent when it really hits the power (and many wont believe it's only 186cc). I've tried a few exhausts ( taffy replica, pm, jl3 etc) and the supertourer has been by far the best
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