Who is good a setting up MAPs

[reciprocity]

You can use the A/F tuning units the fuels mentioned without issue.

These units, with lamba sensors are being used by everyone in Canadian Superbike while running leaded fuels.

[dricked]

So provided my comp ratio isn't extremly high I should be ok with the self tune?

How can I measure my comp ratio without opening the motor?

[caboose483]

So provided my comp ratio isn't extremly high I should be ok with the self tune?

How can I measure my comp ratio without opening the motor?

Should be able to look up the specs for stock. If you know what your squish is you should be able to figure it out based on OEM comp ratio and bore/stroke.

[reciprocity]

So provided my comp ratio isn't extremly high I should be ok with the self tune?

How can I measure my comp ratio without opening the motor?

Contact your engine builder!

[dricked]

Should be able to look up the specs for stock. If you know what your squish is you should be able to figure it out based on OEM comp ratio and bore/stroke.

Contact your engine builder!

I bought the bike with the motor built so I have no clue what my squish is.

I'll see if I can contact the builder, hopefully he still has the specs.

[Brian P]

If the pistons are not stock, the squish clearance compared to stock won't help. You need to "cc" the combustion chambers with the pistons at TDC. I've done it with oil measured by a syringe into the spark plug hole with the engine held so that the spark plug hole is vertical, the tricky bit in your case will be seeing when the oil is level with the bottom of the spark plug hole (because the spark plugs are buried way down inside). If you can figure out a way to do that then you can do it this way. Just make sure you get the oil OUT of the cylinder before you crank the engine, to avoid hydro-lock. You can suck some of it back out with the syringe, then crank the engine over with the starter several revolutions before re-installing the spark plugs. The more you can get out with the syringe the less mess this second step will make Also, for this purpose you only really need to do one cylinder. The others ought to be close enough.

Compression ratio = (Single cylinder displaced volume) / (number of cc it took to fill the chamber at TDC on compression stroke) + 1

If it's 13-ish it ought to be okay on pump premium, if it's 14-ish probably not ...