Krazy Katana

I re-checked spark and noticed that while all four had spark, it wasn't fat or blue. Could fouled plugs be making it run like shit? Carbs are coming off for a quick clean and check, then I will be going for a ride since my new sprocket cover arrived today.

New sprocket cover is on, trying to dial in the clutch to where I had it before. Walking the line between too tight and too loose, seems like I can either get it so it it doesn't drag the motor with the clutch in but it slips, or it drags the motor but doesn't slip. Also, chasing a bastard of an oil leak... Front right oil feed is leaky. Looks like the o-ring pinched on the outside of the head on re-install so it's leaking from the top of the tube. Tried putting some gasket goo on it, but didn't seem to help. I figure the oil is weeping enough that no matter how well I get it cleaned off, it will still interfere with the bond. It's to the point where if I run it then park it for a few hours, it'll leave a small spot on the ground. Debating just trying to use the goo again and just putting the lower fairing on to catch it until I pull the head again... I really don't want to pull the head just to fix a small oil leak, especially without having a garage or shop.

Get a new 'O' ring for oil line. The feeds are at the back of motor. Gasket goo is a real bad idea, seen too many heads trashed when it gets into an oilway
Front right will be a drain back from head so not as 'dangerous'

I replaced the o-rings at the back of the motor, they aren't leaking. It's the drain tube then. It might not matter, since I'm about 30 seconds away from taking this bike to the middle of nowhere and burning it to the ground. I lost the rear brake on my way home from school today because one of the bolt holding the rear caliper on backed out, and when I used the rear brake it snapped the caliper hanger on the side that still had a bolt, and ejected my brake pads to god knows where. I'm tired of having my ride go out of commission for a week or two because of some bs thing breaking.
End rant :-X

30 day warning, oops
Small update, rear caliper bracket is here. O-rings are on order, hoping to take care of the motor this weekend or next. School has been kicking my butt, so priorities have been there. When the motor comes off I'll be re-cleaning the carbs (since they'll be off anyways) and will be doing a proper sync when I have it all back together. Working on the final design for my gauge mount, and playing around with a new fairing made from a different busted fender I had laying around. The lines and shape work a bit better in my opinion. Will post pics once cutting and welding of stuff has begun.

30 day warning, AGAIN. oops
Honestly the bike has been sitting. I have had a busy quarter and lost some steam on this front... I guess in a way I left it sitting because that way nothing else bad could happen. But, I finally shrugged that off today and made a little progress. Rear brake is back together, new bracket and pads installed. Started on the engine tear down, removed the tank, carbs, coils, and moved wires out of the way. I plan on taking the head off and installing new o-rings for the oil drain pipes by sunday at the latest. Working on a design to mount the gauges and fairing. Planning on using a bar of 1/16 x 3/4 aluminum bent and welded in to a cage of sorts. Will this be sturdy enough to hold gauges? If not I'll get some thicker aluminum bar. I have a piece of steel bent to weld on to the back of the fairing, but I need to cut the front for headlight clearance. Any tips on how to stencil out an accurate like to cut on a fender?
Pics will come once anything interesting happens.
Also, a bit of an aside but I checked the jets while I was in the carbs. Pilot is stock (37.5) but main is 120. According to my manual, stock was 112.5. Any confirmation on this? I assume the bump was to compensate for K&N and Exhaust.

Whan mine sits for 10 days r mre, missed like crazy and is a right B***** to start. Usually clears up after 15~20 miles though.
I've got pretty quick at cleaning out the carbs
I'm running 117.5 main jets with 'dual' K&N filters

I won't be surprised if mine sucks to start, especially w/ the carbs not being synced.
At least these carbs are easy to take off and clean.
Think 120 is too big then? Mine has the stock airbox with a K&N built in and a Vance & Hines exhaust. Makes me chuckle because the PO told me jetting was stock.

I would say that's too much jet for stock airbox.
There should be different jets in middle two carbs, I'll have to look up actual sizes, it's in service manual

In the manual it said the different mains are for pre-1990 models, according to manual 90-on (until next gen) all 4 were the same.
I figured +3 might be a bit much for drop-in filter w/ an exhaust.

CALfeRacer said:

You lost me on the second half of that, mind explaining? If I'm thinking about it correctly then bumping up the gearing (3.06 to 3.29) will make it accelerate a bit slower but have a higher top speed and lower cruising rpms, right?

Click to expand...

I forgot to answer this, stock gearing is good for around 140mph with the fairings on.
16t gives too high a ratio for 600.
It lowers rpm but bike is actually slower accelerating and top speed as it doesn't have enough power/torque to pull 165~170mph where you now have it geared

I would use around 110~112.5 with stock airbox and do plug chop

Isn't 112.5 stock? That's what it says in my manual.
Also, IIRC there are a couple of washers under the needle, which would be richening the mixture more.

There are nylon damping washers on needles, thick one underneath clip and a flanged one on top (holds return spring in place as well)
I haven't looked at stock jetting in years, probably 1980's ;D

There were the dampers but I could swear there was an extra washer or two... Not sure so I'll check later. Busy studying for finals today.

If you have any extra washers on needles remove them. Screws up carburation, particularly with stock airbox

Washers wouldn't affect idle, right? I synced the carbs and it still won't idle. Sounds like it's missing down low. I'm going to buy new plugs to see if that helps, and if not then it's back in to the carbs. Pilot screws are all 2.5 out at this point.

Washers will mess up idle as it allows some fuel to 'leak' and become a real crude surface discharge carb

Good to know... I got the carbs close on tune (as close as those liquid vacuum gauges will allow) and it still won't idle. Either sits at ~1k then dies or won't drop below ~2500. I am going to test the plug caps to see if their resistance is ok and trim the plug wires back a bit to make sure spark isn't the issue. After that, I'll pull the needles out. I should be able to pull the caps and slides with the carbs on the bike right?
It's funny, because the PO said his buddy who sold it to him said carbs were stock

Yep, Katana was the easiest bike to work on carbs at the time.
Now, majority of sport bikes have similar frames to 1987 Katana (except in alloy ;D )

is it holding up on the ignition advance, keeping the engine at 2,500? and then if it loses the advance it drops to 1,000 and dies?