No power under 3K, Running bad when hot!

[gageusmc1000]

Hi all,

I have a 1987 FZR1000, 34K Miles, I ride the bike almost daily! I cleaned the carbs thoroughly about a year ago. It runs great when i first start it up and when it begins to warm up. When the bike is completely warmed up(Temp gauge in the center) I've noticed it will sputter around 5K RPM's if I am just easing through the gears, and it will sputter a little bit here and there. However I do have K&N Pod filters on it, with a YOSH Slip on. Not sure about the jetting, but i'd imagine it's been jetted properly because it's very responsive. A part of me thinks that something is breaking down when the bike gets hot(Plugs, wire, coil???) Not sure. Any help would be awesome..


Problem number two.

I have no power under 3K rpm's. The bike falls on its face under 3 Grand and sputters/hiccups. I read the earlier forum about the lad with a 94 Exup, and I can see how that's his problem. Mine does not have an exup valve, so what am I looking at with this issue??


Thanks Gents!

S/F

[Stig]

the lag below 3K may be worn emulsion toobWhats it start like when hot? when were the valve shims last checked?..as you =say, may also be coils breaking down under load when hot

[coops]

Has it been sputtering since you striped the carbs?
I wouldn't be so sure about jetting as a lot of people piss about with filters and slip ons without adjusting jetting accordingly. Both of which will lean it off.
Im not saying this is tour problem though.
Do you have the air box. Try putting it back on there. OR pull a plug and read.
You can chase tour tail with problems like this forever. If it were mine I would first check valve clearances. Then if that doesn't show a problem take it to a good shop with a dyno and they will check the fueling. Get them to diagnose the problem for maybe a hundred bucks. then you can fix from there.

[willandrip]

Emulsion tubes would be my first port of call.
The bike is showing the classic symptoms.
It will never run as smooth thru all rev/throttle ranges with pods opposed to an airbox.
It can be jetted around but Mikuni downdraughts need still air to operate at their best.

Stig neglected to state; He sells tubes at a good rate if required.

Take a tube out and inspect; a close fitting drill bit shank inside the tube aids viewing the wear.
Just holding the tube up to light and looking for ovality of the hole often will not show the amount of wear,
it takes very little to cause the faltering.
By 34k they will need replacement; the price of fuel saved will pay for them in no time.

[Rooster]

I have to give my bike a bit of throttle opening to start when it's hot, it also doesn't like to rev up smoothly from idle to over 3000 when its at running temp. I did not touch the carbs other than replace the screwed up diaphragms and clean the grime off of them. Bike starts pretty well and high idles with out missing and popping, could it be in need of emulsion tubes at almost 30,000 kilometers?

[willandrip]

Tube problem symptoms are more;
Starts without choke from cold.
High fuel usage.
Will not pick up from low revs in a high gear smoothly (constantly having to change down/slip clutch to pick up revs like a tuned 2 stroke)
Gets worse as motor heats up.
How they are ridden has an effect on tube/needle wear. Large throttle openings prevent the needle rattling against the side of the tube. Pottering in traffic with a closed throttle wears them out fastest.
30,000 km is only 18,500 miles ; so not unduly high, but have been proved worn at less than 10k miles.

[Acd92910]

I was searching the board for an answer and I think my question is related, sorry if i'm in the wrong area i'm still new here hah.

FZR 600, 1994. Bogs at anything below 5000 RPM, pods and a jet kit like the OP. Will going back to stock jet sizes/needles and an airbox give me solid power through my range, I just want a nice running bike that has some low end power. The low end on it is garbage and i believe it's the air filters/kit, but it screams above 5-6k. Also, you mentioned emulsion tubes, how do i know when my emulsion tubes are worn I have the carbs out now

[willandrip]

I was searching the board for an answer and I think my question is related, sorry if i'm in the wrong area i'm still new here hah.

FZR 600, 1994. Bogs at anything below 5000 RPM, pods and a jet kit like the OP. Will going back to stock jet sizes/needles and an airbox give me solid power through my range, I just want a nice running bike that has some low end power. The low end on it is garbage and i believe it's the air filters/kit, but it screams above 5-6k. Also, you mentioned emulsion tubes, how do i know when my emulsion tubes are worn I have the carbs out now

Duplicate your post in the 600 section;you will get a better response !
Generally the 600 and 400 variants do not have the same problems with worn needles as the 1000 models or even the TDMs
This is because the smaller engines are generally run at larger throttle openings. (the needles do not contact the tubes.)
Read my previous post for help in deducing wear !