engine

flyingcircus68 · Post by **flyingcircus68** » Fri Sep 06, 2002 8:11 pm

a big bore kit is available which bumps it up to 1029cc. It leaves the walls of the cylinders very thin so they distort a little under combustion pressures and therefore you will consume more oil than stock. Stay away from cometic head gaskets. Let me repeat that again. Save yourself lots of grief and stay away from the cometic big bore gasket. Buy the stock one and carefully open up the holes to match the increased bore diameter, then carefully spread out the outer layers and blow out the grinding dust. Check it over to make sure its clean and the mating engine surfaces also. The cometic company has two types of gaskets for the fzr and they both are crap. the annealed copper corrodes like mad due to the disimilar metals and is not compliant enough to expand and contract. the sandwich gasket they have kind of looks like the stock one except it is aluminum and the center layer is flat. the outer layers have a mildly embossed surface. It looks like it is aluminum. doesn't work to well either. I found that out the hard way. The stock is a steel sandwich gasket which is coated with a teflon layer. the outer layers are coated and flat, the inner layer is very distinctly emobossed. This has the spring back to work properly. The embossing on the cometic gasket is mild, the material is aluminum and will not spring back enough to keep a tight seal. It couldn't be too hard to copy the yammy gasket, I don't know why they can't get it right. As for the annealed copper, what were they thinking? copper is ok on air cooled motors where you don't care about a little leakage and there is no coolant to start corroding the magnesium alloy casting. That is it for me, I'm not chuck d., but I had some relevant info and opinon. flaver flav

ChuckD · Post by **ChuckD** » Sat Oct 19, 2002 12:50 pm

Sorry, I don't usually have a stock pile of pre 89 FZR1000 parts, just that pone that I sold recently. I believe that my colleuge has said it all though. Chuck D.

exupturbo · Post by **exupturbo** » Sat Oct 19, 2002 4:55 pm

I run with a cometic gasket on my 1040 turbo and the first one BLEW big time dumping all the coolant out the top of the header tank. I was too dumb to try filling out an OE gasket and just ordered another Wiesco/Cometic 1040 job. There is no where near enough room to wire ring the exup cylinder block without making it very weak, so I put the block on my CNC mill at work and machined the face down by 0.002" leaving a ring standing up around the cylinders about 0.050" in section. This allowed the gasket to bite down really hard around the combustion chamber, but did not give a problem with the close proximity of the water channels as would the wire ring technique. This operation is probably not need in 99% of big bore conversions, but as it cost me nothing but time, and it seemed worthwhile. No gasket failers since! 170@bhp wheel and rising. Mark

flyingcircus68 · Post by **flyingcircus68** » Sun Oct 20, 2002 9:13 pm

Wiseco o-ringed my cylinder with wire, after I complained multiple times about coolant pressurization. This worked a little while for me until the copper/magnesium alloy combination galvanically corroded enough to leak again. There is no way to prevent the dissimilar metals from acting like a battery. How long have you had your success?

exupturbo · Post by **exupturbo** » Mon Oct 21, 2002 2:48 pm

Mine has been running OK for about 14 months. I think detonation killed the first one,I did make especially sure to well oil the head stud threads and torque down the head in 10 ftlb stages, then I left it overnight and did it again. I fitted water injection at the same time to stop it detonating, how much is down to the injection or my mod I can't say. It just seemed like a good idea at the time. Mark

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