#1 cylinder missing

[Bugg]

I've been having problems lately with that cylinder apparently fouling out, it'll start, sometimes takes a minute to run on all 4, and will cut out at idle until I run for a bit at highway speed, presumably it's finally getting hot enough to burn off all the garbage on it. Plug 4 looked fine the last time I changed them about 6 months ago, so I don't think it's the coil. So, I would either be a bad wire or wrong float height right? Anything else that would cause this? Either way I just bought a newer coil off eBay to use the wires and to have a spare, but I'm just curious which is more likely to be the cause

[paul.miner]

Katanas use a wasted spark system, so although only one spark in a pair is used, they both fire at the same time. If the plug wires will reach, you could swap 1 & 4 as a way of testing the wire.

[Kreylyn]

I think your lean on that carb. Here is why...

Cylinder won't run well when cold, but kicks in when hot...

Rich settings = runs well cold, runs worse hot, overly rich = backfires (loud booms).

Lean settings = Runs bad cold, runs better hot, overly lean = afterfire (small many pops on decel for example).

I think your lean on cylinder 1... Probably a carb setting/cleanliness issue.

Edit to add..

If your "fouling" out a plug from being rich, or missing spark... it generally isn't going to spark later. Fouling out the bike ussually means it won't start and run at all.

If your just not giving enough fuel to that cylinder for a proper mixture to combust when the spark hits... it will kick in later as the plug is fine... just not the right temp and Air/Fuel mixture earlier on.

You won't "burn off" a plug that never fires in that cylinder... so I doubt it's spark.

If you had issues regardless of temp... it would do it hot, or cold... kick in and out a various times, again.. hot or cold... then I would say possibly an electrical issue. Even if it was "only when it's raining"... again, that is something that points towards an arc or loss of spark.

Your symptoms just seams like it's lean.

Krey

[Bugg]

Ok, then I need to get in there and clean it, I was unsure bc the plug is black, all the others are tan, so that to me said rich foul, I'm more used to 2 strokes where lean is burnt white and melted piston lol

[brentwoodkris]

I'm having a similar issue, but with cylinder 2. Did the 'spit' test and verified even after she's all warm, that it seems that cylinder 2 is just not firing. Initially thought it was just a plug, so I replaced all the plugs, #2 was pretty fouled and black and the others just showed normal wear. I guess I'll have to pull the carbs and see what the heck is going on. Hopefully it just needs some cleaner sprayed through it, cuz I just did a full cleaning on them last season and I stored the bike with Stabil this winter... Funny thing is, it sounds like it's running fine even though there's no running on the #2 cylinder. I have no problem with throttle lag or dying. This all makes me wonder just how long I've been running on 3 cylinders...

[kevin2502000]

I'm having a similar issue, but with cylinder 2. Did the 'spit' test and verified even after she's all warm, that it seems that cylinder 2 is just not firing. Initially thought it was just a plug, so I replaced all the plugs, #2 was pretty fouled and black and the others just showed normal wear. I guess I'll have to pull the carbs and see what the heck is going on. Hopefully it just needs some cleaner sprayed through it, cuz I just did a full cleaning on them last season and I stored the bike with Stabil this winter... Funny thing is, it sounds like it's running fine even though there's no running on the #2 cylinder. I have no problem with throttle lag or dying. This all makes me wonder just how long I've been running on 3 cylinders...

My $ is on too low of a float setting causing rich condition.

[brentwoodkris]

Would an incorrect float height cause the cylinder not to fire at all?

[Kreylyn]

Would an incorrect float height cause the cylinder not to fire at all?

Too rich, too lean... both will cause no fire at all... you have to have just the right mixture of fuel and oxygen to get a boom in the cylinder. Float heights will effect both of those.

Krey

[kevin2502000]

I'm having a similar issue, but with cylinder 2. Did the 'spit' test and verified even after she's all warm, that it seems that cylinder 2 is just not firing. Initially thought it was just a plug, so I replaced all the plugs, #2 was pretty fouled and black and the others just showed normal wear. I guess I'll have to pull the carbs and see what the heck is going on. Hopefully it just needs some cleaner sprayed through it, cuz I just did a full cleaning on them last season and I stored the bike with Stabil this winter... Funny thing is, it sounds like it's running fine even though there's no running on the #2 cylinder. I have no problem with throttle lag or dying. This all makes me wonder just how long I've been running on 3 cylinders...

Raise your float level .5mm, you're running rich

[brentwoodkris]

I've never adjusted my float levels before. This should be interesting. So are all the floats supposed to be at the same height or not? I had always thought so, 14mm sticks in my head for some reason..

[loudnlow7484]

I think your lean on that carb.

+1........ my vote is for a clogged pilot.

[Kreylyn]

I've never adjusted my float levels before. This should be interesting. So are all the floats supposed to be at the same height or not? I had always thought so, 14mm sticks in my head for some reason..

14.7mm =/- 1mm for pre kat, stock jetting. -0.5mm if your stage 1 jetting aprox.

They should all be pretty close, yes...

Krey

[brentwoodkris]

Is stage 1 jetting #120's? Cuz that's what I have...so 9.7mm +/- 1mm?

[brentwoodkris]

Okay so this is what I did.
1) Checked out the float height. I didn't have a measuring apparatus but I changed the float so that it was in line with the number 1 and 3 floats around it. It was about 2mm off. I check the main and pilot jets and they were clean. When I pulled the plug it hadn't been fouled yet (fresh plug from a few days ago). I measured all of the A/F screws and this one was about .5 turns out from the others so I adjusted them all to the same which is about 3.25 turns out. After doing all that, now it seems that the number 2 carb is running, but according to the 'spit' test, it's not running near as hot as the other carbs. I'm really not sure what that means or what I should adjust next.

[Kreylyn]

Okay so this is what I did.
1) Checked out the float height. I didn't have a measuring apparatus but I changed the float so that it was in line with the number 1 and 3 floats around it. It was about 2mm off. I check the main and pilot jets and they were clean. When I pulled the plug it hadn't been fouled yet (fresh plug from a few days ago). I measured all of the A/F screws and this one was about .5 turns out from the others so I adjusted them all to the same which is about 3.25 turns out. After doing all that, now it seems that the number 2 carb is running, but according to the 'spit' test, it's not running near as hot as the other carbs. I'm really not sure what that means or what I should adjust next.

Spend a $1 and get a ruler that has mm measurments. Mark and cut out a 14.7mm slot from an index card. You have a quick easy cheap float height tool.

If those are not spot on... your bike won't run right. Period.

Krey