'90 GSX250F running rich... again

[KingJackaL]

My GSX250F Across has had its carbs done by shops twice so far this year. And this last week it's gotten to the running-so-rich-it's-not-even-idling point again. After the last tune, my bike was getting 18km/L, it now gets 12.

*sigh*

I'm getting sick of spending the better part of $500 for a mechanic to tune the carbs (I mean, they do a decent job - fuel economy and power were great after both tunes), only to have fuel economy shot, starting be a problem and the engine running WAY too rich just 3 or 4 months later. Rinse, repeat.

I've done a fair bit of riding over the last week (just over 1000km), so it's way worse than it was just 1 week ago (even 2 days ago it idled, now I have to keep the revs over about 2-3k). Engine temp is beginning to go up as well, which 2 tunes ago was what happened the day before the bike completely died. I've taken spark plugs out, and yes - they're covered in black.

Last time I had the carbs done (and oil/filter changed, for a WoF), they replaced the carb slides as well.

Q: Is getting your carbs done every 3 months/2000-3000km normal?
Q: If not, what could be needing replacing/fixing so I don't have to be spending this much $$$s?
Q: Can anyone show me how to do the carbs myself? Be MUCH cheaper for me in the long run .

[michael]

Hey mate, by all means Im not a mechanic so dont quote me on any of this, but I had similar problems on my 89 CBR 250. My carbs were giving me huge problems, bike was spitting and spluttering. I changed the fuel line, this included lines, fuel filter, and checked my fuel pump with a 12V battery (ended up replacing my pump cuz some dodgy mechanic who no longer works in NZ told me that it was fucked when I took it home and tested it and it was fine). Anyway I cleaned my carbs out ($300 later) from a bike shop in town and bike was fine......for a couple of weeks....then back to square one. So I got sick of paying a shit load and went to a pretty rough looking guy out the back of mt wellington. He told me to take the carbs out, bring em to him and he'll sort it out. He said you can do it at home but without the right solution to soak it in and the wee brushes to clean it out with its a pain in the arse. So took it to him and he charged me $30 and the bike was purring like never before after.

Like I said I dont know much, but this guy told me some of the bike shops aren't used to fiddling with older bikes and some guys dont do proper jobs of cleaning it out (some guys just soak em instead of brushing them clean).

I also went through $300 in spark plugs before I fixed the problem. You're jets might also be rooted, but I don't know how to tell (can't remember).

Anyway I feel your pain, and I know how f**king frustrating it is...took me a year to figure mine out and just about emptied my pockets to

[KingJackaL]

Hmm, found the receipt from the last service - turns out that was on the 8th of August, so just over 2 months ago. Funny - time flies when you're having fun, I thought it was 3 or 4 months ago. Will stop by the shop and see if they'll fix it up (CGA and all that).

[kiwi cowboy]

My GSX250F Across has had its carbs done by shops twice so far this year. And this last week it's gotten to the running-so-rich-it's-not-even-idling point again. After the last tune, my bike was getting 18km/L, it now gets 12.

*sigh*

I'm getting sick of spending the better part of $500 for a mechanic to tune the carbs (I mean, they do a decent job - fuel economy and power were great after both tunes), only to have fuel economy shot, starting be a problem and the engine running WAY too rich just 3 or 4 months later. Rinse, repeat.

I've done a fair bit of riding over the last week (just over 1000km), so it's way worse than it was just 1 week ago (even 2 days ago it idled, now I have to keep the revs over about 2-3k). Engine temp is beginning to go up as well, which 2 tunes ago was what happened the day before the bike completely died. I've taken spark plugs out, and yes - they're covered in black.

Last time I had the carbs done (and oil/filter changed, for a WoF), they replaced the carb slides as well.

Q: Is getting your carbs done every 3 months/2000-3000km normal?
Q: If not, what could be needing replacing/fixing so I don't have to be spending this much $$$s?
Q: Can anyone show me how to do the carbs myself? Be MUCH cheaper for me in the long run .

wot k's has the bike done? If its high it could well be the jets but have you checked the choke is'nt sticking on slightly?[just an idea]

[KingJackaL]

wot k's has the bike done? If its high it could well be the jets but have you checked the choke is'nt sticking on slightly?[just an idea]

It's done about 25.5k. The shop that did the 'fix' 2 months ago is looking at the bike today/tomorrow, so I'll get their analysis tomorrow hopefully. But yeah, it could be anything in the fuel system - jets, needles, fuel lines, pump etc. Apparently similar bikes to mine (the smaller, older GSX/CBR's) do often have issues around the fuel pump not switching off properly.

*waits till tomorrow*

[KingJackaL]

Got the bike back today. The shop saw it as a warranty fix (which I was hoping would be the case *phew*) - turns out the choke cable was on a bit all the time. Which explains a lot (low mileage, doesn't need choke to start if it's above 0 degrees, plugs foul over time, etc). So they've fixed the choke cable, replaced the spark plugs and tweaked the carbs a little to lean things off.

And now the proof shall be in the running - if the bike's still happy in another 4 or so months, then that will have been the problem all along. And if that's the case, I think it'll be duty to take some beers around and say thank you, cos this one's been bugging me for almost a year (since I bought the bike).

NOW

RIDE TIME!!!

[KingJackaL]

Well, it didn't last the 4 months.

Short version: do the pics attached indicate the bike is running too rich?

Longer version: *sigh*

I'm finding it very hard to trust bike stores, although I don't think they're actually trying to rip me off. It seemed to be running fine out of the store, but within a week I had to go overseas for a couple weeks, so I wasn't able to burn a whole tank to check how it was going.

Well, the last 2 fill-ups I did were both for about 9L of fuel, and I got about 120k each time. *sigh*, 13k/L. Even worse than before. The bike is actually running, sure - even idles with the headlight on (once warmed up). But that's abysmal fuel consumption.

It could be a leak - but when I got home today I pulled a plug out, looks like it's running rich again:

[miSTa]

Not running rich at all: http://www.dansmc.com/spark_plugs/sp...s_catalog.html

[KingJackaL]

OK, hmm. Maybe it's a leak then? I'll double-check the lines from the fuel tank - maybe a pipe has cracked, or there's a faulty inline filter or something.

Thanks for the reply.

[raspygold]

Hi there King, just wondering if you've noticed a drop in performance as well or flat spots in the rev range? If so you might want to check your throttle slide holders.
My bike, also a '90 Suzuki gsx250f Across is having similar problems at the moment. I've found some pretty interesting stuff on the internet about it though.

Have a read here:
http://au.geocities.com/ozcross250/holder.html