The CDI box.

[89katana750]

This example is brought to you by the 1990 GSXR 750 and the 1989 GSX-F Katana 750.

When swapping the gsxr engine into the katana frame should someone be concerned with getting the CDI box from the gsxr rather than keeping the katana CDI?

The specs on the ignition coils are different so we put in the gsxr coils.

However, the CDI box on both bikes read the same in the specifications.

resistance is:
2.4 - 3.2
30, 000 - 40, 000

I thought it would be fine (after all it works fine) except for that the bore and stroke are different on the two bikes, and Suzuki has two different part numbers for each CDI box.

what do you guys think? Should I worry about it?

[Black_peter]

I think matching the ignition to the engine would be the first choice. If you need to use the coils off the Kat with the GSX-R engine and CDI box then you need to see that the Primary coil resistance is the same (or close) that is the small number. Too big a difference could damage the CDI. Bore and stroke is not applicable, timing is though. I am curious if the timing is biased through the Kat CDI, after all the signal for the timing is coming from the crank. So the signal matches the cams. However is the timing retarded (or advanced) based on Kat cams? So using the Kat CDI with the Kat coils is fine as long as the ignition timing matches the engine timing.

I would look at the "installing larger engines" thread and see if Special K mentions that.

[Special K]

I'd TRY the Kat CDI, but the GSXR CDI is best as it should operate that engine per the factory.

THey MIGHT have the same ohms ratings and such, but I'll bet they operate slightly different...........