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Low Compression Engine

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rpeters
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Low Compression Engine

#1 PostAuthor: rpeters » Tue Feb 25, 2020 7:16 am

Looking for advice here!, i have a Z1000 MK engine with 1197 displacement and 7.8:1 MTC flat top turbo pistons. Question is can I use this for non-turbo with larger carbs and what are the consequences in running with the lower compression or is it not advisable and better to replace the pistons?

Any guidance much appreciated

Rob
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Julian_Boolean
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Re: Low Compression Engine

#2 PostAuthor: Julian_Boolean » Tue Feb 25, 2020 8:54 am

The low compression will make it slow and feel a bit unresponsive, it'll probably run on paraffin though.
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zed1015
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Re: Low Compression Engine

#3 PostAuthor: zed1015 » Tue Feb 25, 2020 10:25 am

Shame it wasn't 1075cc.
I would have swapped for my new 10.25-1 block and pistons.
That said. It's going to feel a bit "off" with the drop in compression if going carbs.
I would either build it proper with the correct pistons or give the head a skim.
1mm off will get you around 9.5 -1.

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Re: Low Compression Engine

#4 PostAuthor: Ultim8pc » Tue Feb 25, 2020 10:37 am

My initial thoughts were to skim the barrels too.
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rpeters
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Re: Low Compression Engine

#5 PostAuthor: rpeters » Wed Feb 26, 2020 6:44 am

so maybe, i should change the pistons, what size and any suggestions on make?...then what Carburettor recommendation please?

Rob
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Re: Low Compression Engine

#6 PostAuthor: zed1015 » Wed Feb 26, 2020 9:26 am

All depends on what the goal is.
I prefer to keep it simple for the road and go 1045/1075cc Wiseco or MTC.
Common size, stock block and will produce enough trouble free reliable power without the increased risk of oil leaks, overheating or wear issues a big block gives.
Stock 26/28 work fine and won't need any bigger than 33mm slide carbs at the max.


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