Thread: Stroked crank

There is a local company that can stroke most cranks. Won't get into the details but they can turn my 86mm into anything up to 94mm.

Now, what would be a better build.

a 90mmx90mm

or

a 88mmx94mm

the 90mm bore is expensive because of the sleeves, so preferably I'd like to stick to max 88mm bore, but I need to understand all the pro's and cons of such a build please.

price? plz

94 will need some block shaving to work.

lulz if you think boring will be expensive compared to everything you need to do to run a stroker

You will need to do some serious grinding on the motor, you will need custom rods, and possibly pistons depending on how this is built.

I would go with the biggest bore. It is cheaper, and you can rev more easily.

THat's just it. The crank work is not expensive. It's the same price for any stroke, so I can do anything from 87 up to 94.

I was also thinking of a square block like 90mm x 90mm but I want to hear what the pro's and cons are of going long or oversquare.

The crank work works out to $350 before cryo treating. And about $600 total. They also do the necessary changes to the rods you want to use. Which brings me to the next question, what rods will I need if I go say 90mm or 92mm?

I realize the block may need some work as well to clear this crank, but engineering here is relatively well priced.

how exactly do they stroke the crank?? heres a place near me that will make a stroked crank from scratch to your specs.. but to take an existing crank and stroke it that would mean cutting and welding which on a crank is that even possible???

Wedliing and regriding


Not the best for long term.

They weld the shaft journals then regrind them. Normally this is done if a bearing chews part of the crank journal and to save money on buying a new crank.

Yeah I know it's not the 'ultimate', but for the money it's a fair compromise. Cause when we talk long term, what exactly are we saying, 40,000kms? I'm at a stage now where I don't think I'd expect any build to last that long, because we're always looking to upgrade and try new things.

Couple of guys I spoke to mentioned they've used this companies cranks in local racing spinning them to 10k+ rpm with no issues.