Katana Owners Club U.K.

A big bore kit available for the 750 pop-up engine? And how many models shared the same 750 engine?

Yes i believe there is a wiseco kit, could be around 844cc, but not sure off the top of my head.. the engine is the same as the GSX750 ef/es/efe, all the monoshocked aircooled GSX750 versions were the same basic engine, there are a few differences with the popup, but nothing that'll effect the top end. If yours is a jap spec bike then some GSX cams would perk up the top end a bit too.

I have been searching for that kit but its possible that it has been discontinued.
I know one of yours is now a 1230. What type of engine did you replace the standard? I saw a pic of it on the strip. Do you have anymore to tease us with?

Hope Mal doesn't mind me saying on his behalf, but his engine was/is an 1100EFE lump. The frame was altered (height and length) to allow it to fit, quite major surgery.

The Wiseco kit is discontinued (I think they did 816 and 844) but they appear every now and then. Keep an eye on ebog Germany as the last one I saw (but got outbid on) was there.

Someone has hopefully already researched it but there must be some other pistons that would do the job.

I think we touched on this subject on the old site but can't be arsed to search..
I have a catalogue somewhere from 86/87 that lists the big bore kits available.
I know TTS Towcester Tuning Shop (remember them?) did an 890cc kit & Wiseco did an 844cc one.

They occassionally appear on Yahoo Japan but go for silly money

I was raeading a thread on the OSS site and someone was searching to find something that might fit. Will see if he got anywhere.
The only reason im asking is because my No2 Cylinder has been diagnosed with a terminal illness and possibly needing a rebore. Was investigating other possibilities.

As Chris said fairly major surgery, the engines a bored out EFE, was making 152hp back in the early nineties, it will live again, but not this year, got other things planned.
I havn't got many pics on the computer, here's a couple from around 92 and one taken a couple of years ago...It has a nice spondon swingarm now (but no pics yet)




As for your pistons, if you find out the gudgeon pin and bore size then you can search around for a possible alternative, the gsxr750 engine isn't too disimilar and if they suit there's probably more piston options.

Thats a pretty badass lookin Pop-Up. Too bad you wont get the latest incarnation finished soon enough. If i wasnt saving for a holiday back to OZ i know where all my spare wedge would be going. Thanks for the pics and info.

Not really much in the way of help in big bore kit questions, but if you need another engine tut suit I have one here ES really but low mileage,£50 to club member as that is what it cost me, I'm sure the system an get it to Lndon.