Katana Owners Club U.K.

Hi,

Does anyone have any experience regarding jetting the katana?

I bought mine with Cones installed (and some 4-1 italian exhaust). The bike run good, so I thought that cones + exhaust, got the dyno and tuning therapy. But as I inspected the carbs - jets are stock...

there is no kit from Dynojet or Factory pro... So... Any tips? starting point? that would save some time as a starting point?

Thanks in advance....

Is that Italian exhaust a Termignoni? Very common back in the day. Nice sound, a little flat spot revving around 4 - 4,5 k.
There was no rejetting required as long as you ran the stock air box and filter. Maybe you got a pic of that exhaust?

Do I get you right - you already ran your bike in the described setting and it ran fine? What about the sparks? How did they look like? Any white(-ish) debris around the exhaust outlet?

I found this Jetting Guide on the SOHC/4 Owners Forum useful as a starting point on my 400:

http://forums.sohc4.net/index.php?topic=58112.0

hard to believe in such a linear progresion of sizing... + there is not even 1 word, about needles... so it looks like a pretty useless tutorlial if You want to do things the correct way... but it's a interesting read.

I was hoping to get feedback for this particular model though:)

Pedda wrote:Is that Italian exhaust a Termignoni? Very common back in the day. Nice sound, a little flat spot revving around 4 - 4,5 k.
There was no rejetting required as long as you ran the stock air box and filter. Maybe you got a pic of that exhaust?

Do I get you right - you already ran your bike in the described setting and it ran fine? What about the sparks? How did they look like? Any white(-ish) debris around the exhaust outlet?

will check the markings on the exhaust today.

I know the bike runs good, as my friend sold it to me. He said he made 200 miles on it before taking it apart. the spark plugs look ok.

As I wrote - I was sure that after puting the cones on, and custom exhaust - the original owner must have made some carb changes. But it turned out that he didnt'. In this case I can't believe that it doesn't run lean. Will have to figure it out by myself soon

jimbo22 wrote:hard to believe in such a linear progresion of sizing... so it looks like a pretty useless tutorlial

That's why I said "starting point" That was the best I could find really when I needed to get an idea for jets on my 400 - you gotta start somewhere some how.
Nigelkat in getting his 550 to run right, had 19 dyno runs in the end with carbs tweaks inbetween - http://www.katanaownersclub.co.uk/forum ... &start=320

Re: the 400: Even up on 2 jets sizes it was better from 7k rpm, but around 10k starts to lack power again, so not sure whether to go up another jet size or raise the needle by one notch which was a possible recommendation on here.

Rob

This is from dans recent dyno run. does that help?

Pete

on full throttle and high rev, needle is not important. its fully open anyway - so ONLY main jet is the topic here.

callyboy wrote:This is from dans recent dyno run. does that help?

Pete

Thanks. It helps a little. proves that pods don't kill the engine totally... i can see that there is only 1 main jet size up installed. Do we have more dyno chrts? to see the 1/4,1/2, 3/4, full throtlle power band?

I think I saw one from him. will ask him.

Pete