Advice wanted: Kawasaki ZR250 cutting out

[Vinz0r]

Hey there guys, yesterday I went for my first long (1hr+) ride on my recently acquired Kawasaki ZR250. The trip was Hamilton to Auckland and after checking oil (was a little low but nothing drastic) and water I set out. I was doing 100 - 110 on the way up with no troubles, bike was going well, when all of a sudden I noticed that it was responding slowly and erratically when I gave it gas for overtaking etc, about 30 seconds later it stopped responding at all and the revs died off, I managed to get across the lanes and onto the verge before it died completely (while I was still rolling, and in gear). This was about 5 KM south of the Greenlane east exit, so was after about 1 hour 30 mins of riding.

My first thought was that it had overheated, but the light (no temp gauge, just light to signal overheating) was not on. I had a looksee at the oil (glass window thing, not a dipstick), and while it wasn't high, there was some there. Checked the reservoir water tank, still full. I let it sit for awhile, then tried to start it again, it spluttered a bit but wouldn't catch, so after another 10 minutes I tried again, this time it started alright, had to use a bit of choke to keep it going but after 30 seconds of that she was idling fine. I jumped onto a nearby offramp to find a gas station, pulled in and topped up the oil. Let her idle for awhile, nothing seemed to be wrong so I completed my journey (was headed to a friends house for a visit).

The next morning I get up to head home, about 10 KM's north of Pokeno the same thing happens, bike stops responding to throttle and revs die, before cutting out altogether. So I pulled over, checked spark plugs, oil and water again. She doesn't seem too hot, and after 15 minutes she started again. I thought that maybe I was flooding it somehow, but geenrally after flooding don't you get a big could of nasty smelling smoke coming out of the exhaust? I had nothing like that happen.

After I got her started again I headed down to the nearest petrol station and let her sit for a half hour while I got a coffee, jumped back on and she was running fine. I took it easy sticking to around 90 and didnt have any trouble, but when I got past huntly I decided to open it up a bit and see if she died again, sure enough after about 5 mins of 100 - 120 she started to play up again, as soon as I felt it I chucked her down into fourth to see what would happen if I kept the revs high while decelerating. Ended up cruising at 60 in 3rd and while she still didn't want to accelerate much she wasn't stalling.

I pulled over and let her sit for awhile, then jumped back on and headed back into Hamilton, didn't have any trouble until I was 200m from my house, then she started to do it again, managed to get into my driveway before she died though.

This problem has left me very bloody confused, I am rather new to motorcycles, have very basic mechanical knowledge, and would really appreciate it if anyone could give me a clue as to what is going on with my bike. It's an intermittent fault so is going to be hard to reproduce in a workshop unless they go for an hours ride to make it happen which may make diagnosing it rather difficult.

Bike is a 1991 Kawasaki Balius (ZR250) which has an inline 4 very similar to the ZXR250's of the same era.

Cheers,
Vin

[Vinz0r]

I posted this over in the General Maintenance forum as well, but thought I'd put it here also as I'd assume more people who own 250s frequent this forum.

Yesterday I went for my first long (1hr+) ride on my recently acquired Kawasaki ZR250. The trip was Hamilton to Auckland and after checking oil (was a little low but nothing drastic) and water I set out. I was doing 100 - 110 on the way up with no troubles, bike was going well, when all of a sudden I noticed that it was responding slowly and erratically when I gave it gas for overtaking etc, about 30 seconds later it stopped responding at all and the revs died off, I managed to get across the lanes and onto the verge before it died completely (while I was still rolling, and in gear). This was about 5 KM south of the Greenlane east exit, so was after about 1 hour 30 mins of riding.

My first thought was that it had overheated, but the light (no temp gauge, just light to signal overheating) was not on. I had a looksee at the oil (glass window thing, not a dipstick), and while it wasn't high, there was some there. Checked the reservoir water tank, still full. I let it sit for awhile, then tried to start it again, it spluttered a bit but wouldn't catch, so after another 10 minutes I tried again, this time it started alright, had to use a bit of choke to keep it going but after 30 seconds of that she was idling fine. I jumped onto a nearby offramp to find a gas station, pulled in and topped up the oil. Let her idle for awhile, nothing seemed to be wrong so I completed my journey (was headed to a friends house for a visit).

The next morning I get up to head home, about 10 KM's north of Pokeno the same thing happens, bike stops responding to throttle and revs die, before cutting out altogether. So I pulled over, checked spark plugs, oil and water again. She doesn't seem too hot, and after 15 minutes she started again. I thought that maybe I was flooding it somehow, but geenrally after flooding don't you get a big could of nasty smelling smoke coming out of the exhaust? I had nothing like that happen.

After I got her started again I headed down to the nearest petrol station and let her sit for a half hour while I got a coffee, jumped back on and she was running fine. I took it easy sticking to around 90 and didnt have any trouble, but when I got past huntly I decided to open it up a bit and see if she died again, sure enough after about 5 mins of 100 - 120 she started to play up again, as soon as I felt it I chucked her down into fourth to see what would happen if I kept the revs high while decelerating. Ended up cruising at 60 in 3rd and while she still didn't want to accelerate much she wasn't stalling.

I pulled over and let her sit for awhile, then jumped back on and headed back into Hamilton, didn't have any trouble until I was 200m from my house, then she started to do it again, managed to get into my driveway before she died though.

This problem has left me very bloody confused, I am rather new to motorcycles, have very basic mechanical knowledge, and would really appreciate it if anyone could give me a clue as to what is going on with my bike. It's an intermittent fault so is going to be hard to reproduce in a workshop unless they go for an hours ride to make it happen which may make diagnosing it rather difficult.

Bike is a 1991 Kawasaki Balius (ZR250) which has an inline 4 very similar to the ZXR250's of the same era.

Cheers,
Vin

[Bald Eagle]

My first thought is some part of your electrics is overheating after a certain amount of time at load.

[onearmedbandit]

Could be fuel starvation. I had a bike a few years back that had very similar symptons to yours, turned out to be related to the petcock assembly. I took it to bits, cleaned it out, reassembled and never had the issue again.

[Crasherfromwayback]

Check the fuel tank breather isn't blocked.

[Devil]

Check the fuel tank breather isn't blocked.
Yep, my suggestion too.

[Crasherfromwayback]

Yeah...it's quite common for them to be blocked...or that the hose is squished/bent sharply hence not allowing any air into the fuel tank! Quick way to tell...when the bike stops...open the tank, and if it's blocked...you'll hear air rush into the tank when you pop the top!

[porky]

as above . If that dosnt work i would be looking at your float level. High rpm it craps out??

[Vinz0r]

Just had a looksee for any bent hoses but couldn't find anything. Will have a poke around this weekend and see what I can find in the way of blockages. Yeah it seems to be mostly when accelerating past 8-9k in 6th gear, doing 100 - 120, so engine's under a bit of load.

[Crasherfromwayback]

That's when it's using the most fuel...so I'd say for sure you've got a fuel supply issue

[neels]

If you've got a bit of time to muck about with it, wind it up until it stops then shut it off quick and remove the drain screw from one of the carbs. If almost nothing comes out that might answer the lack of fuel question. Not pretty but probably the easiest way to find out.

To check for a blocked breather, just find a nice straight bit of road, wind it up and see if it stops. Once it's going again crack the fuel cap a bit and repeat, if it doesn't stop that's the problem. Probably better with not much in the tank unless you want a petrol bath though.

[Grasshopperus]

Hi Vin,

It sounds like you've got a fuel problem there (nothing to do with the oil by the way). The next time you've got a problem like that, pull over and open the fuel cap, if you hear a pop or hissing sound it may indicate the cap needs a clean. In any case, opening the cap and then closing it again may fix up your problems.

I'm no mechanic but if you'd like you can come round to my place in South Auckland on Saturday or Sunday during the day and we can do some basic maintenance like oil filter, oil, carburettor clean and inspection, radiator flush,spark-plug clean and anything else we can diagnose.

Let me know if you'd be keen for that.

Cheers
Al

[Katman]

I'd be checking for water in the fuel.

[Slyer]

Yeah it must be something to do with the fuelling. If not that possibly to do with the ignition, it may be shorting out somehow. Was it raining at all?

Install a fuel filter for starters between the fuel tank and the carbs and make sure that your fuel tank isn't rusty inside.
Is the fuel old at all?

[Tryhard]

I pulled over and let her sit for awhile, then jumped back on and headed back into Hamilton, didn't have any trouble until I was 200m from my house, then she started to do it again, managed to get into my driveway before she died though.


Cheers,
Vin

Maybe a dumb ques. but any chance you are running out of fuel? Did u try switching to reserve?

[Slyer]

I think if he knows how to check oil level he knows how to check fuel level...

It's possible he may be running out of fuel, not because the tank is empty but the fuel tap is gummed with rust or other crap.
Fuel tank, fuel tap and fuel lines are the first things to check.

[Devil]

So next time you have the problem, open the fuel cap and see if there's a vacuum there.
Something else to consider (mentioned above) is that it could be starving of fuel which could mean the float level in the carb is incorrectly set. I may have had that issue with that bike before (cant remember). A good way to test this is find a really long piece of uphill road (so you're on an open throttle for longer). If it starts to feel like its running out of gas towards the top then this could be your issue.

[JR1]

yeah id have to agree with prior posts in regards to fuel line or tap issues, the problems your bike had are similar to when your running out of fuel at motorway speeds (yes iv done that - no fucking fuel gauge...).

[Vinz0r]

Ok, turns out the problem was fuel related (surprise surprise), I got a pm from a previous owner of the bike and he threw some light on the situation for me. It turns out that after not being used for a little while the aftermarket inline fuel filter empties out and doesn't refill itself completely, so under heavy load it just doesn't pass through enough fuel. Fixed this by removing the filter, refilling it and connecting it back up. Has stayed full over the past couple of days, went for an hours hard riding out in the country with plenty of heavy acceleration and didn't have any trouble at all. Checked the filter afterwards and it was full.
Now I just have to find out what causes the thing to drain and not refill in the first place..

(Also, I checked whether there was a vacuum in the tank after a bit of riding but there wasn't so I don't think it's a breather problem, unless it's only partially blocked and that may be what causes the filter to have trouble refilling)

Thanks for all the help guys, that's what i love about KB, everyones keen to lend a hand!

And Grasshopperus, in regards toy our offer, I may just take you up on that next time I'm going to get her serviced :D Cheers!

[Vinz0r]

Tencharacters!

[Devil]

Good to hear its (sort of) sorted. I was the first NZ owner of that bike, it didn't have that fuel filter in it when I had it.

[Vinz0r]

Devil, do you know where I could pick up a cheap replacement speedometer for the Balius? I managed to snap mine off the internal mount (don't ask how) and while it is glued back on now, it's only a matter of time before it breaks again. I had a new one priced at around $390 which I thought was a bit steep! Or do you know if any other models would go on easily?

[Devil]

Pass. Not sure if you can go digital with it (trailtech or something).
Might just have to go OEM.

[Slyer]

Might just have to ask around at wreckers, otherwise look at fixing it yourself it paying someone to.

[Vinz0r]

Yeah it is fixed at the moment, and working fine. but it is a bit old anyhow, the faceplate on it is a tad faded and it doesn't look very nice. Just looking for an excuse to get a new one really, and if I could get a nicer looking assembly to replace it with that'd be super. I wonder if it'd be possible to replace it with a digital one.. Any suggestions on where I'd go looking for one at a decent price? (Would help if it included revs also.)

[Devil]

Bling it, yo!
http://www.bits4bikes.co.nz/accessories/trail_tech_enduro_accessories/1183.aspx
Universal kit.

[Vinz0r]

Soooo.. an update on this situation, it has still been having this issue whenever I go for long rides, I replaced the fuel filter which did nothing to rectify this issue, and was about to take it into the shop a couple of days ago to have it looked at when I decided to try one last thing.

I drained the tank, whipped the fuel tap off and opened her up to have a look inside.

I think the picture speaks for itself..

229812

So after cleaning it all out (found a piece of red plastic lodged in there as well), I'm hoping she'll be running fine. Will have to go for a longish ride to test it so will probably head out to raglan later in the week.

[Slyer]

So the tube for your main fuel setting is snapped off? Would have been fine running on reserve then heh. You're running an inline fuel filter right?

[Vinz0r]

So the tube for your main fuel setting is snapped off? Would have been fine running on reserve then heh. You're running an inline fuel filter right?

That little thing poking out is a small filter, the main fuel line doesnt have one though, which might be why one of the previous owners added the inline fuel filter (I guess they didn't think that the tap would become clogged up with rust and whatnot). The one with the filter on it is for 'prime' setting.

Yeah there's an inline fuel filter so I am not too worried about putting a new filter on the tap inlet. If it becomes blocked again I will put one on, but hopefully that shouldn't happen in a hurry.

(Also, the reserve doesn't work, apparently it had been disconnected by a previous owner as well!)

EDIT: Is there supposed to be a tube running up from the main fuel line inlet so that it doesn't use all the gas and leaves some for reserve? And does the reserve line run off the same one as the prime? If so it makes sense why the reserve function doesn't work.. maybe I'll have to find a tube to pop in there to fix it, would stop a lot of the rust and crap getting in there too.

[Slyer]

No no, it should have two connectors like this.
http://akhara.com/nc30/fueltapmod/images/0.jpg
The longer tube sucks from higher up and thus cannot touch the "reserve" fuel that the shorter tube filter can.

[Vinz0r]

Hah, you posted that just as I put that edited portion in my previous post, which was asking what you just explained.

Cheers :D

[Slyer]

To answer your other question, yes the prime runs off the same as reserve.

[Hurrie]

Hey
Vin

EDIT: just read your comment above so ignore this!!
I had the exact same problem with my old cbr250 turns out that the inline fuel filter was blocked up so that it would die whenever i needed the gas or sometimes when i was just cruising along. and exact same symptoms as yours sometimes it would start after 10 mins sometimes it took a little longer to get it started. First thing i did to sort it out was check if there was a build up of rust in my petrol tank (which there was) gave the tank a good clean and seal and than changed the inline fuel filter and i was good to go!!

i hope that helps and goodluck!