700s rich mid range

[TDodge7]

My 700s has been having a problem where it gets too rich between 5-7k , not so rich that there's any stumbles or flat spots but you can definitely hear it get blubbery and crackly in the exhaust as you make it to 5k which is right about where I generally cruise . It's much worse while the bike is warming up but it's still present to a much lesser degree once it's fully warmed up , it also seems to do it slightly worse on cold days . Everything is stock on the bike except for a foam uni filter . Now tuning isn't my strongest point but I can only think of 2 things that could cause this and that would be having the slide needles clips in the wrong position , or a clogged air filter . My air filter is a foam uni filter so right off the bat you would expect a freer flowing filter to make it run leaner , and if it were clogged you would expect the engine to run rich throughout the entire range . The filter still looks new , it's still got all it's oil which looks clean as well so I'm doubting that's the case . Leaving me with the slide needles , mine aren't adjustable , if they were I could just set the needles one notch leaner which would almost certainly fix the problem since it's only getting rich to the point that the exhaust gets annoying , and not really effecting performance . But I searched around on here and couldn't find anyone with a similar problem , or anywhere I can get adjustable needles (except for that expensive dyna jet kit which frankly is out of the question $$$) so has anyone else dealt with this or know any neat tricks like adjustable needles from another bike that will work on the 700 , maybe from the Canadian 750?

[TDodge7]

....anyone ?

[Brittles]

Have you had your carbs apart? Maybe the previous owner put some washers in there (doubtful)? Maybe you could adjust mixture screws.

[tomb raider]

Had my S out last night for a fasttttttt 18 miler. I went back to the OEM air cleaner to see if it mad a difference. I had oil issues under it in the box, K&N. When I had my carbs off I want to say I had 135 main jets. Rick as hell on warm up, you can smell the fuel at a stop. Kinda burbles on take off but I can live with it. I thought I was having oil blow by on start up but it's fuel...    

My K&N is going back in....  I think it ran a tad better with it 

[gammer]

....anyone ?

Tdodge, from the symptoms you have given, its tells me that you are actually running a tad lean in the mid range. Since it is worse when the bike is cold or when it is cold out, then this indicates a lean condition. If it was worse when the bike was warmed up or the air temp is warmer, then this would indicate a rich condition.

You are correct that the needles are not adjustable on our bikes (including the CDN 750 model). I would suggest that since the only change you made is going to the UNI filter, then that is your culprit.

The true test would be to put a stock filter back on and see how it runs. If the mid range issue goes away, then you know for sure.

BTW, do you use the air box lid when using the UNI filter?

[TDodge7]

it's had the uni filter the entire time I've owned it so it wasn't something I changed that's suddenly causing this . As far as it running better when it's warmer all I am really backing that up with is that last summer with the same setup it didn't seem to do it as much . Also I went to a friends house the other day , when I got there it was around 60 degrees , it was doing it pretty bad . When I left my friends house is was in the low 50's and it was even worse (though I will say I didn't warm it up nearly as long). I do know that if I turn the choke on while it's doing it it gets WAY worse , I'm fairly certain it's rich , especially with the plugs being on the darker side of correct . There's no washers or anything under my jet needles . All my jets are stock , and yes I run the uni with the lid on , otherwise nothing would get filtered . I'm going to take a ride around the block with the filter out of the box and verify if being leaner makes it better or worse .

[tomb raider]

Sure sounds lean, could it be a spark issue or electrical ? Timing off ?

How come that robot never runs out of ammo or melts down the barrel 

[gammer]

I'm going to take a ride around the block with the filter out of the box and verify if being leaner makes it better or worse .

Removing the air filter will be too drastic.

Here's what I would do: On the snorkel that is attached to the top of the air box lid, I would duct tape half of its intake off...this simulates a richer condition. Try driving the bike like that and see if it gets worse or better.

[tomb raider]

 What Gammer said, except I call it Riding. Maybe differant in Canada 

[TDodge7]

OK , interesting results . First I warmed the bike up and took it around the block with everything in . As usual it idles pretty well , full throttles no problem and starts getting blubbery at 5 . So I pull back up to the house and ditch just the air filter , take it for another spin , with 0 difference . So I swing back by the house and lose the air box lid , this time it's definitely lean as idle isn't great , the middle is still pretty bad , and wide open is no good . So I pull back up the house again and this time I run inside and grab my color tune plug , put everything back together and tried it on cylinder 1 and cylinder 4 because the tank is in the way  . Here is where it gets interesting , at idle the flame in the cylinder is blue , though perhaps slightly on the lean side , if I only give it 1/8 to 1/4 throttle nice and smooth and rev up to 5-6k I can now see that it appears to be running DEAD ON PERFECT , perfect bunson blue , this makes no sense . Richness shows it's self pretty obviously on the colortune , it's definitely not running rich , at least when it's not under load anyway . With the colortune there is however a fine line between lean and perfect as lean is still blue but lesser so , so I won't write off the possibility of it being lean since it was blue . Hmmm I'm going to need to think about this one .

[muttstang]

are you sure that the carbs are clean?

[TDodge7]

The tank is spotless and the carbs were ultrasonically cleaned by me last summer , it's been getting semi regular usage all winter , I only keep a gallon in the tank during the winter so that every week or so I have to put in another gallon of fresh gas (keeps the gas from getting old while I'm inside staying warm most of the winter) . But I haven't been back in them . It's done this the entire time I've owned the bike .

Is it possible that my idle mixture is too lean and when it transitions to the proper mid range mixture it breaks up ? because like I said the idle does look a bit on the lean side , but mid range looked pretty dead on . I badly need to get one of those special screw drivers for adjusting these mixture screws .

[muttstang]

I would advise filling your tank to the top all winter.  with all of the water that is in fuel these days, you are going to end up with condensation and rust in your tank by not filling it all of the way.

[TDodge7]

The bike sleeps inside , I built a concrete ramp into the house , it gets to relax in the 70 degree awesomeness all winter . I just do that so that there's never any gas sitting in it older than a few weeks .

[tomb raider]

I want a pic of her in side    Put some SF in there

????????  Color Tune Plug  ???????????

[TDodge7]

The colortune plug is a spark plug with a glass window in it so you can see the color of the flame in the combustion chamber . and here is a pic of the back room , 3 bikes in it right now .




anyways , here is an update , I pulled the carbs to verify everything is clean , and it is , all jets are original and all pilot screws were out 2.5 turns except for one that seemed to be out a little more , but someone was talking to me and I losrt count so we'll never know. There are no washers or anything under the needles . I tried taping off half of the intake under the seat and it didn't seem to do much . Luckily I've been waiting for an excuse to pull the carbs so I could install the allen head kit since my screws were looking pretty sorry . Not sure where to go from here , idle seemed like it was a touch lean , but the factory calls for 2 turns out and mine was 2.5 so I can't imagine it being far off . Took a better look at the air filter and I'm 100% sure it's not blocked up . So short of shimming the slides richer I'm not sure what to do . any ideas ?

[TDodge7]

Ok well I ordered one of those long 90 degree mixture screw tools , and got a bag of washers from radio shack . I guess I was wrong about the richness , but before this bike my old xs1100 had a problem with being ultra rich and it sounded exactly the same so I was stuck thinking rich , the colortune said otherwise . So in the next few days I'll be colortuning my idle , resyncing the carbs and doing the washer mod (which would make sense as to why my mixture screws are out farther than stock and why the midrange is lean , freer flowing air filter ) so we'll see how that does . Man I love having the right tools , If you work on multi cylinder bikes on a fairly regular basis you owe it to yourself to pick up a gunson colortune , and a morgan carbtune ...and in the case of the 700s with it's annoyingly bad placed mixture screws the motion pro mixture screw adjusting tool .

[gammer]

I have one of those 90 degree mixture screw tools. I use it for adjusting the #3 carb. The rest I can get at with a very small flat head screw driver.

[TDodge7]

Well the weather said it was going to snow tomorrow so I figured I better get some work done now . Did the washer mod , mixture will have to wait for a nicer day but it's close enough . so I did 2 washers on each needle and I'm happy to say it's better , maybe not perfect but much better . Holding the throttle at 1/4 there is still a very small flat spot near 6k and every once in a while I hear it getting a tiny bit blubbery , or at least I think I do ...but maybe I'm just crazy . And with 2 washers on there it's not like there's any room for more so this is physically as rich as I can make it anyway so I guess it'll have to do . And perhaps it will be perfect once it warms up some . Sadly though my left most carb bowl o-ring has decided to start leaking and now I'm out of cash so I guess I get to smell that wherever I go now unless it decides to swell up and fix it's self before I get more money and rip those carbs out again.

[TDodge7]

just found a small split near the engine in my petcock vacuum hose , it was loose enough that it probably was sucking air , I'm sure that wasn't helping , that cylinder has always run a slight bit leaner than the others ...now I know why. I'm still not sure what to do about these leaking float bowl o rings , they're $44 a pop from honda so that sure as hell isn't going to happen . I might be able to swell them some with brake fluid or carb cleaner . If I flip them over the mating surfaces are much better looking , I may try flipping them all over and giving it a try . If not maybe I can put a tiny bead of rtv under the gasket to stand it up a little bit . What a pain this is , I can have the carbs out in 2 minutes flat though so that's something I guess. The rest of the plugs look a little rich now , I wonder if once I fix the hose the 2 washers will be too much as that hose could have been causing a good portion of the popping , at least I can change that with the carbs on the bike . Still waiting on that mixture tool to get here .

[tomb raider]

Ebay Man, there much les.....   I didn't think the washer mod was any good on the 700s ??

[TDodge7]

the "washer mod" applies to any carbs with non adjustable needles that needs mid range richening because of exhausts or intakes etc. , it's not just a nighthawk trick. In my case I have a freer than stock flowing air filter which makes it run leaner ....plus that leaking vacuum hose which was definitely making one cylinder super lean . I did end up finding cheaper gaskets but I'm broke for another week and a half .

[muttstang]

I got my float bowl gaskets here:

http://www.crc2onlinecatalog.com/Index_Main_Frame.htm

[muttstang]

and no rtv on the float bowls.  gasoline will eat that stuff up

[gammer]

Tdodge, did you get the mid range issue sorted out?