hi how do you all lower the compression for an r1 motor. do you put the gasket on the bottom of the cylinder. or a thinker head gasket. and what boost can you run with this set up.
thanks adam

you could buy a decompresion plate how much lower you need it are you on for a turbo conversion

what about forged pistons to lower the compresion

here you go http://www.je-pistons.co.uk/product_info.php?cPath=618_8030_8049_8053&products_id=1631132

ANOTHER engine idea?

Forged pistons are nice but not the cheapest and depend on someone making them for the R1. An aliminium decompression plate from someone like Ferriday engineering is a good option and not hugely expensive (and they can make for any engine given a DXF).
Putting (or even making) a thick gasket to go between the two bits of a two part block is not only cheap but low-tech (the block shouldn't be pressurised after all).
The advantage of going for Forged pistons is that they'll likely be designed to maintain some squish which you often lose with decompression head gaskets or extra block gaskets.

Then again, when I went to TTS and was talking to them about decomressing my ST1100 before adding the blower they recommended doubling up on OEM head gaskets for a moderate decompression.

If you haven't read Bell's book on forced induction tuning (recommended) and you're trying to work out what boost to run with what compression have a look under my photo archive for a graph showing boost vs compression ratio (CR).

[Edited on 29/11/07 by BenB]

ALLOY BARREL SPACER TO CORRECT DECK HIEGHTS VARIOUS SIZES £45.00 http://www.mbcustoms.co.uk/30322/info.php?p=7&pno=0 hope that helps malc will sort it out for you he is a star

You can only use a barrel spacer if you have a seperate barrel though chaps

The R1 (like the carbed blade) is a 2 part block*, not a 3 part block like the busa etc, so the barrels are cast as part of the top half of engine casing.

That narrows the options down to thick head gaskets or a change of pistons.

Chris

*not sure about later engines but this is true for up to 2003 engines.

go with the pistons dude you know it makes sence or chance melt down but its up to you lol

[Edited on 29/11/07 by imp paul]

Judging by the number of different engine's oadamo has asked about in recent months on Locostbuilders, I think by the time he actually decides the only choice he'll have will be between a hydrogen cell and a nuclear fusion reactor