Hi, all just pulled motor down to find out i had broken the crank what i would like to no what is required to stroke a crank thanks . The crank i got is a large jnl with nos 1505 stamp on it

you will need a set of 521 cooper S rods, get your crank crack tested { cross fingers} hope its ok then get it offset ground to suit the cooper S rods. i think you end up with 83.8mm stroke if you use std bearings.

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120bhp with 450kg just fun waiting to happen

We were prob. drunk when we set it up last and thought this will be a good idea

I got mine to 84.33 stroke with std bearings- mind you, it was standard to start with.
Could/should have got even more by grinding it a bit further undersize...

Note- you will need to machine about 1/32" off the width of the S rods to fit the crank..

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

how far under size do you go crank is at 30 under now needs machining again

I am building a motor for an ausmini member at the moment, with a stroker crank. The crank was 1.750 -.060", it has now been offset ground to 1.625 -.030". Stroke increase was about 2.0mm.
Bearings are still available at -.040", and the owner has a set of -.060" squirelled away, in case.

Although the crank was already -.060" and obviously had done a lot of work, it was NOT cracked.. it's the 1st thing I check when I get a crank.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

best to start with a std crank,,, that way you get the most out of it

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Very true- however if you do own a worn one it's still worth doing, rather than leaving the stroke at standard..
How's the stock of -.080" bearings going these days, Matt?

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Always make sure you get the crank Nitrided when stroking. Not cheap but worth doing.

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DID I MENTION THAT I AM THE BEST SUPPLIER FOR MINI ELECTRICAL PARTS AND REPAIRS?
"Let us remove your "SHORTS"

only problem is you run a good chance of it coming out looking like a banana

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1970 Cooper S ex-Bathurst & ATCC
1964 Austin Cooper S ex-Group C race car
1967 Morris Cooper S ex-Group B
1962 Mini Speed sports sedan
1968-71 ex-Peter Manton Shell car

Mine was -.010" and I ended up with 1cc less than Kevs at the end of all the offset grinding.

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the world is a book, and those who do not travel read only a page
66 Mini Minor sponsored by http://www.lifeonthehedge.com.au/ The Dog Harness Specialists
It was a pleasure ausmini. I'll miss all you misfits and reprobates

I'm building a stroker (for a road car) at the moment with a `scatter crank'..
When the owner passed it on to me it was already at -.060", and we wondered why. Spiro then offset ground it to [S size -.030"] but found #4 crankpin had already been restroked in the past, probably because it had damaged a crankpin somehow.
Anyway, long story short, this crank has been stroked 2mm on 3 cylinders and by 3mm on #4. I decked #4 piston more to keep deck height of all 4 the same.
We'll keep you posted on how it runs..

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

OOooo,,, i don`t like thems ones, i had customers with "Thingts" like that before... not a very even "Banging" going on inside,,, not a very well balanced thing at all

YUK

but hey... if it`s only a little out then it`ll "sort-of" be like a low comp in one pot,,,sort-of

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Don't worry Matt, it's only going in a Morris 1100. What's a few extra vibes...you probably won't feel em in that, they have real engine mounts.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

hee hee,,, yeah like a late model jap car, soft & goo-y,, no worries tho, they go & go & go,,, & not going to be reved so not really an issue,,, seen em plenty of times before, soooo may crank grinders make a boo-boo with differing strokes, happens all the time , especially on the old machines where it`s all left to the opperator to make em all the same length (& angle i might add ) just don`t like em is all

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.