streetshee Posted November 17, 2003 Report Share Posted November 17, 2003 last week had carb prob on my 2003 shee,throttle stuck open and then died and only just ran around tickover for max 15 seconds,so stripped em,cleaned(although didnt see a trace of dirt) but noticed on the slides where they had contact with carbs was rubbed in places(slides are a sort of black paint coating?) anyway,put her together,took a 150 mile trip,no probz then thismorning on way to wk the throttle stuck open again!!! cables are perfect free,now im wondering if the scrapes in the paint on slides are not (sometimes)letting the slides return again properly? does anyone know the prob or a trick on what to do? have thought about putting a stronger spring or another one as well in the slides,good idea or bad? by the way,tors is removed,have twist gas and idle kit. please help cos i nearly killed myself thismornin,was cornering very fast on a real twisty road when stuck open,my trousers need washing now sorry people i think i put this post in wrong section?! i pay attention next time. Quote Link to comment Share on other sites More sharing options...
Yamahammer Posted November 17, 2003 Report Share Posted November 17, 2003 I just had the same problem with my 03 but the slides are not sticking as far as i can tell... But it runs like they are i was checking the throttle while they where stuck and no play at the throttle so i thought slides not stuck but if you hit the kill switch on and off it would idle normally again. I am thinking maybe an air lock or vapor lock senario is causing it. There was a long post on the old forum i am trying to find it but it looks to be lost at the moment.. I was talking this through with EVIL and he said there was never a problem solver that came up on that post and we where both comming up with the same ideas. I checked everything also even swithed needles out for different ones and same thing sticks about 1/4 throttle and everything is clear clean and not binding... 1> I wonder if it makes a differance when you bolt the cable holder on the slide if the hole gets blocked in the slide or open in the slide. 2> I was also thinking that the carbs get hotter than the slide which tigtens up on the slide causing it to stick??? 3>Vapor lock or something of the sort like an increase in fuel pressure like a full tank of gas and the tank not venting forcing the gas into the carb.. 4> Maybe a lean or rich spot on the pilot and it is burning off the excess fuel or leaning out. i know my jeting is right but since i rejetted it started doing this may be a coincidence but who knows bike only has 8 to 10 hrs on it?? 5> I was going to take some emry and scoth brite pads ant try to polish out or remove ane inperfections in the carb slide bores a good idea or not??? Any one have any good tips or somewhere to start looking..... Quote Link to comment Share on other sites More sharing options...
Holyman Posted November 18, 2003 Report Share Posted November 18, 2003 The theories abound!!! We went 17 pages I think on the old forum and couldn't SOLVE the problem. My latest thinking is that it's a problem with the choke tube between the carbs. I suggest trying this... go to the auto parts store and get 2 rubber caps and remove the choke hose and cap both ends of the little nub sticking out of the carbs. It will be harder to start without the choke on the RH carb but I think the problem is there. fixitrod was able to see that the slides don't in fact get stuck wide open but only about .10 inches which is about even with the choke tube/port. We've pretty much eliminated the stronger spring method, the vortex around the slide theory, the vacuum at the top of the slide theory, the with black coating/without black coating method, the w/ or w/o TORS theory, the water in the airbox/ on the filter theory, the randomly tight cable theory, the "it doesn't happen on bored stock carbs" theory, the "your quad is a POS" theory, the ambient temp outside theory, the water in the gas theory, and pretty much any other theories I might not have remembered. There are 2 things that always occur when the slides stick {as far as I can tell}... 1- there has to be high humidity and/or wetness. 2- the quad has to be revved for at least a short period of time. There is one thing that has never happened { to my knowledge} this has never happened on the RZ350 which runs the same carbs and is essentially the same engine. I say that whoever helps resolve this problem must patent the resulting remedy and whoever has posted a theory or remedy should get an equal share of the income.Let the brainstorming begin!!! {again} Quote Link to comment Share on other sites More sharing options...
SDD Posted November 18, 2003 Report Share Posted November 18, 2003 Are you sure the throttle tube isn't rubbing on the handle bar causing it to stick? Double check the throttle cable clips aren't blocking the hole in the slide. Quote Link to comment Share on other sites More sharing options...
fixitrod Posted November 18, 2003 Report Share Posted November 18, 2003 The theories abound!!! We went 17 pages I think on the old forum and couldn't SOLVE the problem. My latest thinking is that it's a problem with the choke tube between the carbs. I suggest trying this... go to the auto parts store and get 2 rubber caps and remove the choke hose and cap both ends of the little nub sticking out of the carbs. It will be harder to start without the choke on the RH carb but I think the problem is there.fixitrod was able to see that the slides don't in fact get stuck wide open but only about .10 inches which is about even with the choke tube/port. We've pretty much eliminated the stronger spring method, the vortex around the slide theory, the vacuum at the top of the slide theory, the with black coating/without black coating method, the w/ or w/o TORS theory, the water in the airbox/ on the filter theory, the randomly tight cable theory, the "it doesn't happen on bored stock carbs" theory, the "your quad is a POS" theory, the ambient temp outside theory, the water in the gas theory, and pretty much any other theories I might not have remembered. There are 2 things that always occur when the slides stick {as far as I can tell}... 1- there has to be high humidity and/or wetness. 2- the quad has to be revved for at least a short period of time. There is one thing that has never happened { to my knowledge} this has never happened on the RZ350 which runs the same carbs and is essentially the same engine. I say that whoever helps resolve this problem must patent the resulting remedy and whoever has posted a theory or remedy should get an equal share of the income.Let the brainstorming begin!!! {again} Amen!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!11 Quote Link to comment Share on other sites More sharing options...
Yamahammer Posted November 18, 2003 Report Share Posted November 18, 2003 thanks guys and yea i never got into the old post and nowit is gone I hear ya on the throttle sticking at the 1/4 point i will try the choke tube and go from there all cables are free As far as humititiy yea it was on sun and it rained sat and also at a high altitude so i cleaned the bike up today and tomorrow i will tear into it hopefully i can get it worked out... Could it be a bad batch of carbs every so often and the slide bores are out of round? any body mik them Quote Link to comment Share on other sites More sharing options...
streetshee Posted November 18, 2003 Author Report Share Posted November 18, 2003 some very good ideas,personaly i now think it could be something to do with moisture or the choke tube? was fairly wet air both times when it happened,i see what happens thismorning,thanks guys for lots of effort and help,hq is the best forum!!! Quote Link to comment Share on other sites More sharing options...
fixitrod Posted November 18, 2003 Report Share Posted November 18, 2003 There is a definite moisture problem with the mikuni stockers. I use to make it fail by running water over the top with a garden hose and revving it. It usually took a minute. See if you can get it to fail that way so you have a base for your testing. It may help everyone if you find the choke tube to be the problem. Quote Link to comment Share on other sites More sharing options...
Yamahammer Posted November 20, 2003 Report Share Posted November 20, 2003 I took the carbs off today and this is what i found I was blowing air in the transfer ports for the choke tube and got moisture out of the L carb the moisture will follow either two paths into the slide tunnel or the intake tract.These ports are located on the front or motor side of the carb in the slide tunnel,the other is on the motor side also but in the exit body of the carb on the left side(or right if you are looking into the carb from the motor side). On the L carb the transfer port goes into the intake tunnel with the choke CLOSED or in the slide body and intake with the choke OPEN BUT with the choke closed air will leak out slightly past the choke needle rod in the slide tunnel.( poss what is causing the problem is that maisture accumilates in the cavity and when heated by riding or by boncing it around it works out these two spots.It appears there is two places for the water to enter.If you look at you're carbs you will see two brass plugs in the carb body to block the holes made for manufacturing i think on some carbs and with heat expantion of two disimilar metals that this is where the water is entering and leaking onto the carb slide causing it to bind and hang.. On the R carb the coke port goes in from the top and only in to the exit of the carb the motor side and is located on the roof. My solution i used JB weld and sealed over the plugs so there is no way water is getting in there now i don: know if this was the problem or a cure but i thought i would share it with you and see what you thought.. I will test it this weekend and see how it goes. I also thought that mabe the hole was cloged to the R carb when i blew air in the choke tube hole it took alot of force then got easier but i could have been imagining things. Quote Link to comment Share on other sites More sharing options...
Yamahammer Posted November 20, 2003 Report Share Posted November 20, 2003 Has anyone ever tried two right carbs and blocked the choke tube off. mabe it is the left carb causing all the problems Quote Link to comment Share on other sites More sharing options...
Holyman Posted November 20, 2003 Report Share Posted November 20, 2003 At one point I thoerized it was frost or freezing of the high humidity on the engine side of the slide. I even used an old pair of carbs and hooked it up to my shop vac and ran water in the fuel line just to see what the temp would be. As it turns out, the coolest temps I got {by touch because the rectal thermometer I used doesn't read below room temp} was just above idle or about even with the choke port. Now that someone has found water in the choke tube, I say plug the tube at both ends and then run the hose over it and take it for a ride. Should be obvious if that's the problem. Quote Link to comment Share on other sites More sharing options...
Yamahammer Posted November 20, 2003 Report Share Posted November 20, 2003 The only problem is i rode in a little water the week before and it stuck like twice i thought maybe it didnt.Then i washed the bike at the Quarter car wash on the way home and did not start it or wipe it down then a week later i took it out and it stuck so bad you could not ride it un safe. cleaned them i thought 3 times and it still did it so i put it up.This is what i have found out since then.. Quote Link to comment Share on other sites More sharing options...
fixitrod Posted November 20, 2003 Report Share Posted November 20, 2003 Yammahammer, your finding are very interesting. Holyman theory was the freeze theory mine is a vacuum of some sort. The reason I find it interesting is the position the carbs to stick. The stop just below the choke holes you are talking about. The reason I think it's vacuum is because the slide drop the second the motor stops. They don't stick anymore. I don't have stock carbs anymore because I was afraid sand was going to make it's way through my choke. I felt a little grinding on the choke when I pulled it out. This was after my first trip to the dunes. Before that, I was the guinea pig for testing because I could create the trouble with a garden hose everytime time. Quote Link to comment Share on other sites More sharing options...
Yamahammer Posted November 20, 2003 Report Share Posted November 20, 2003 the choke tube actually flows air between the carb even in the off position so mabe it is vacume related that the water stops the vacum bypass between the carbs or something.. I will try the carbs today with the hose and see what happens.. Quote Link to comment Share on other sites More sharing options...
streetshee Posted November 20, 2003 Author Report Share Posted November 20, 2003 ok,maybe i got it guys!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ive put 2 small hose clamps on the pipe between carbs,seems to hold them a little tighter,its dead fiddly an awkward to do,tried the water test,seems ok,will see over the next few days,my shee lives outside with a cover over her,the air is very damp here at moment so if shes gonna stick then it will be soon,i keep ya posted..................................... Quote Link to comment Share on other sites More sharing options...
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