Carb cleaning, adjusting, tuning

[stretchmiester]

With the recent posts about issues possibly related to the carbs, what is an expected price to pay a mechanic to get my carbs adjusted, cleaned, tuned, whatever and to have them check out my floats and make sure everything is running right?

[lossimo]

I have a mechanic coming to my house to clean and sync my 7 he says between $100-$120.Around 2-3 hours of work he says.
Seems fair to me since I can have it done at home.

[stretchmiester]

Bump.....Anyone else have any ideas on pricing?

[Hammerhead]

Originally Posted by lossimo

I have a mechanic coming to my house to clean and sync my 7 he says between $100-$120.Around 2-3 hours of work he says.
Seems fair to me since I can have it done at home.

A mechanic that comes to your house?

[Hammerhead]

Originally Posted by stretchmiester

Bump.....Anyone else have any ideas on pricing?

Shop labor is in the vicinity of $65/hr. 3 1/2-4 1/2 hrs to remove, clean, replace and re-synch + parts. A good shop will put a rebuild kit on each carb. This replaces the gaskets, rubber o-rings and float needles. $20-$25 per kit x four. Probably a minimum of $350 to have it done right.

[ZX7RJoe]

Originally Posted by lossimo

I have a mechanic coming to my house to clean and sync my 7 he says between $100-$120.Around 2-3 hours of work he says.
Seems fair to me since I can have it done at home.

If he knows what he's doing it sounds like a good price,I've never heard of a legit mechanic that makes house calls though...Guess we'll see.

[ZX7RJoe]

I figured maybe I could continue on this thread for cab tuning rather than opening a whole new one since this one seems to have been dead for a little.

Now that the overheating issue on my bike is at least somewhat resolved and I've been able to ride it I'm going to go ahead and get into some carb tweaking/tuning.

The other week when I had them apart to clean them I set all of my floats to 13mm and all of my pilot screws to 2-1/2 turns out as a base setting.Since I've been running it I've noticed some problems from idle to around 4 or 5k.The other day on one of my longer rides it was really sputtering and hesitating all throughout that range.According to the link to CV carb tuning that Supra put up the other day: (http://www.factorypro.com/tech_tunin...m_engines.html) my float height and pilot screw settings could be the issue.It's exhibiting all of the signs that the tuning guide talked about for tuning issues within those rpm ranges.

So I pulled my carbs today and made these adjustments:
- float height 15mm
- pilot screw 2 turns out,even.
- carb for cylinder 4 had one shim on jet needle while all others had two,set them so that they all have just one shim.

I wasn't too worried about the jet needle height or the main jet size for now since it seemed to run great after 5k all the way up,even if there was an issue with the main jet size I don't think I have the extra funds right now to play around with that so I'll have to tune around it.Honestly not sure how much jets are anyway.

I'm gonna run out and reinstall my carbs quick yet tonight,the next day that the weather is decent I'll run it and let you guys know what's up.

[zaneyzrex]

Originally Posted by Hammerhead

Shop labor is in the vicinity of $65/hr. 3 1/2-4 1/2 hrs to remove, clean, replace and re-synch + parts. A good shop will put a rebuild kit on each carb. This replaces the gaskets, rubber o-rings and float needles. $20-$25 per kit x four. Probably a minimum of $350 to have it done right.

that would be right on .....oh and im one of those techs that will come to your house and do the work if possible..... i would rather it be in my garage w/ all my tools but if its simple ill come to you...

[e1_ZX-9r]

Originally Posted by ZX7RJoe

..
So I pulled my carbs today and made these adjustments:
- float height 15mm
- pilot screw 2 turns out,even.
- carb for cylinder 4 had one shim on jet needle while all others had two, set them so that they all have just one shim...

TIP
Joe - for best results, anytime you make fuel delivery alterations to the pilot air screw or float height (or pilot jet, for that matter), synchronize your carbs afterwards. I go as far as to synch them every time I remove them. I can see from the synch tool and from how she runs that there is a difference.

[ZX7RJoe]

Originally Posted by e1_ZX-9r

TIP
Joe - for best results, anytime you make fuel delivery alterations to the pilot air screw or float height (or pilot jet, for that matter), synchronize your carbs afterwards. I go as far as to synch them every time I remove them. I can see from the synch tool and from how she runs that there is a difference.

I haven't ever synched my carbs yet,the process seems simple but I don't have the tool(s) for it.What tool or instrument do you recommend?As soon as I can get some more money together I'll pick one up or order one.

[e1_ZX-9r]

Hit the Carburetor Synchronization how-to link I posted back in March. All the information is linked in there.

Never done it, huh? You're gonna like her even more afterwards for sure!!

[ZX7RJoe]

Originally Posted by e1_ZX-9r

Hit the Carburetor Synchronization how-to link I posted back in March. All the information is linked in there.

Never done it, huh? You're gonna like her even more afterwards for sure!!

Sweet,thanks for the info,I should be able to order one next thursday or so.

[ZX7RJoe]

I went out and started my bike up this evening for the first time since I made the adjustments,after some cranking and eventually a jump enough fuel got to the carbs to fire up.

This time,as with the last time I made adjustments,the rpm was erratic while the choke was set,climbing to 4k then down to near stalling then to 3k,2k and so on...Had to feather the throttle to keep it running.After it's warmed up for a minute and I back the choke off it seems to run fine...Strange,I set the idle to 1100rpm,it doesn't run smooth as silk (never did) but it holds just fine.

Once it warmed up I blipped the throttle a few times to see if the idle richness issue was any better,it went right up and came back to idle with minimal "hang up".Before it used to drop below idle,too rich,so my pilot screw adjustment seemed to take care of that.

Decided to take it out for a quick run around the neighborhood.Seemed to run a little better in the 3k-4k range which is where the trouble was before.There's still some kind of a small stumble or hesitation in the low low rpm though,between idle and 2 or 3k.

The weather is supposed to clear up for us later thursday or friday,I'll take it for a real run and let you guys know how it does so I can go from there.

[ZX7RJoe]

Took her out for a ride today,the bike seems to run better,no soggy area in the 3-4k range anymore so that's good.Just one complaint...

When I start it up it's a little erratic with the choke on but once it's off it runs fine,idling somewhere between 1100 and 1500 rpm.So I took it down my normal stretch of road for a few miles,the first red light I came to I noticed that my bike is now idling at 3-4k rpm,I blipped it quick to see if the cable was just stuck but no,the idle speed increased for some reason...I immediately rode it home in case this was some sign of a bigger issue (I don't need to be stranded along the road,that's fur sure) and parked it.Upon parking it I turned the idle back down to around 1300 rpm and the bike was fine...Why would the idle rpm change so dramatically???

[e1_ZX-9r]

Based on the fact that your last mods were to lean the mixture relatively, the "now runs rough on choke" (like a normal cold ZX, great off choke) and RPM increased dramatically after it was warm, probably meant that the low-speed circuit a/f ratio was off-the-scale rich before, like 11:1 or something...which also will make hot starting much easier now as apposed to before.

Why? Going back to your ride, the idle speed was holding the butterflies open a little bit and resulted in idle at 3K-4K. Being that was how it was setup for the previous richer mixture, more air would cause a lean mixture to give the sensation of running out of gas, whereas an overly rich mixture would require more air just to keep from drowning the cylinders.

Test: Go for a 10+ minute ride so everything is up to temp and return home. She should idle where you have her now. Blip the throttle and see how quickly RPM returns to idle.

Quick = good/normal
slow hang = lean

If normal, see how she starts hot. Probably better now.
If lean, change float height to 14mm and try again.

[zaneyzrex]

good ideas from E1 but hes missing one very important thing... turn your idle down to 1000rpm (maybe even less with your bike) if you have the idle set to high you not only have the pilot/idle circuit feeding fuel you also have the TRANSFER HOLES starteing to feed fuel.... it wont be consistant off the transfer holes so its gonna act weird .... turn the idle down and make sure its not lean on the pilot (as said above , rev - comes back smoothly/quickly then its fine....... rev - HANGS then its lean , turn screws out another 1/2 turn)

[ZX7RJoe]

Might have been a false alarm,I ran it to the gym and back tonight with no issues,returned right to idle every time.The problem might have had something to do with the fact that when I started it up before I forgot to turn the fuel tap to "on",it started slowing down so that might have been when I turned the idle up a little.I turned the fuel tap on once I realized it but the fuel system might have been playing catch-up while I was riding and ended up resting at a higher idle...Just a thought but it seems fine now.I'll try another longer run tomorrow just to be sure.

Originally Posted by e1_ZX-9r

Test: Go for a 10+ minute ride so everything is up to temp and return home. She should idle where you have her now. Blip the throttle and see how quickly RPM returns to idle.

Quick = good/normal
slow hang = lean

If normal, see how she starts hot. Probably better now.
If lean, change float height to 14mm and try again.

You're right,it starts right up when hot now,I tested that earlier today.It used to be impossible to start when hot.

Originally Posted by zaneyzrex

turn your idle down to 1000rpm (maybe even less with your bike) if you have the idle set to high you not only have the pilot/idle circuit feeding fuel you also have the TRANSFER HOLES starteing to feed fuel.... it wont be consistant off the transfer holes so its gonna act weird .... turn the idle down and make sure its not lean on the pilot (as said above , rev - comes back smoothly/quickly then its fine....... rev - HANGS then its lean , turn screws out another 1/2 turn)

I have my idle set at 1100 right now,per my manual.Would you suggest going lower?I'll give it a whirl if you think it would help.

When I rev it it returns right to idle for the most part,not instantly but it doesn't hang at where I revved it to or anything,does that sound right?Within what time frame should it return to idle,1 second or so?

Sorry if it sounds like I'm being too particular,I just want to get this thing right.Thanks a lot for your help guys,it's appreciated.

[zaneyzrex]

snds like ya got it figured out... its not really a instantaeous return to idle since all those hard parts have to slow down lol.....

[ZX7RJoe]

Took it for a longer ride today,probably close to 2 hours and the bike ran great,still getting that little stumble in the 2-3k range but I can deal until I get the carbs synched.The bike ran cool too,I don't think the temp ever even got close to half way on the gauge.I'm really happy with the way it's running now so thanks again for the help/tips guys.

I do have one small issue;the gas cap leaks.I filled her up before I headed out,after that any time I got on it a little or took a moderate to sharp turn gas would run out of the cap and get all over my jeans and shirt...Man that stuff burns when it sits on the inside of your leg for an hour or so.

Is there some kind of rubber seal involved with that that I might be missing?Anyone else run into this?

[e1_ZX-9r]

That's awesome about how she's running! Yes, the synch will smooth most, if not all that low RPM crap out. At least, smooth her out enough that you may forget about it.

As for the gas cap spilling. Start a new thread. Nobody will catch it buried down here.