Katana Owners Club U.K.

Since i bought my pop up in October i have to admit its hardly been looked at because ive been too busy keeping body and soul together !

Yesterday i finally got around to removing its winter cocoon (ive not got a garage or big enough shed !) to make a mental shopping and to do list. I noticed that the engine and frame numbers dont match.

The frame is GR72A-119***
The engine is R703-127***

Is this just how Suzuki made them, or has mine got an engine from a 750es ?

What makes you think there is something wrong with the numbers?
Firstly engine numbers and frame never match , they have no correlation except in adverts in mags where people selling old stuff want more money for 60,s and 70's stuff.

R703 is the engine fitted to both the ES and SE . Only the colour of the covers are different.

The only import thing
Is that the engine number on the log book is the same as the actual one fitted , but in all honesty if it isn't it can be changed at no cost so isn't that important.
So vehicle. Don't even have the engine recorded.

I did not know for sure if the engine and frame numbers where supposed to match, thats why i asked. Thankfully the numbers on my bike match the log books.

As far as i can remember both of my rg500s had matching engine and frame numbers. Suzuki's from that era appear to have a different system for their two stroke bikes. Yamaha's rd350lc and ypvs had matching numbers for certain, ive owned two ypvs's.

According to information gleaned from this forum the se put out 72-77 bhp at the the crank, the es a claimed 90 ! The difference in power is, im lead to believe, because the es has smaller carbs with bigger jets and slightly different cams, so the differences are more than engine cover colour deep.

Thanks for putting me straight on the frame and engine numbers.

Different power outputs for different countries, but engine prefix remains the same for SE/ES/EF.

From memory The ES was 85hp, later EF was 90, Aus/NZ/SA spec SE's were 90hp, Jap spec SE/3 were 77hp. Carbs for full power SE were supposed to be bigger but I've only measured Jap spec SE and UK ES ones which have been the same, ES has different jetting to the SE though.