Hello, everyone, and Merry Christmas to all.

I have the classic hanging idle problem:
Bike starts cold with choke (enricher) engaged. I have to pull the throttle a bit or else it dies. After a minute or two, it revs up to about 4k. At that moment I can get going w/choke on. About 10 min later, I can release the choke and go to "normal", but if I stop, the revs go above 4k. I control them with the clutch, which I know is just killing it.
Anyway, this week I'm off work, and I will solve this problem with your help. Yes, I have read just about every post there is about this issue. I'm not checking my valves until I work my way to them - I recently serviced the engine w/new rings, honing, valve lapping.

Today I took down the carbs. First thing I find is sediment. Brick colored dust in both bowls. I'm thinking "this is good", because I'd rather have a definite reason for things being what they are.

Here's my first question: My bike is an 02 (I know it's really an 01) and has the carbon canister for emission control. However, it is disabled. It isn't connected to the carbs. Furthermore, the carbs are Mikuni 01DQ/T5X1 and don't have the nipples at the bottom where the hoses that go to the carbon canister connect. They do have places that look like that would be where you'd put the nipples, but I suspect that there's nothing there (there's no hole going to the area under the butterfly)

In the pics you can see 4 tiny holes under the butterfly, 3 for the jets and one for the mixture screw (some people would still call it the "air screw). In an older carb body that has the nipples for the canister, I can see those 4 tiny holes, as well as a bit larger hole that is directly above the nipples. (I can't use that carb body because it is incomplete)
My question is, am I correct in that this particular carb doesn't have a via for a carb canister nipple?



Second question: What would be recommended to clean the fuel tank?

Third: Should I change the petcock under the tank?

Fourth: Seems to me that to cancel variables, I should also replace the other petcock (how do you call it?), the one that you turn the valve to set the flow to RES/PRI/ON?

So, that's my battle plan: 1. Clean the tank 2. Change the fuel petcock valve (and the one under the tank if you really recommend it) 3. Add a fuel filter 4. Thoroughly clean the carbs (again)

If this battle doesn't with the war, then I guess it would be on to the valves.

Thank you all for your help, guidance and suggestions.

Mauricio

Another question: Say I want to check the fuel petcock valve. As I understand it, both RES and ON supply fuel only when vacuum from the carbs open a diaphragm that lets fuel circulate at the petcock; fuel only flows when the engine is on. PRI, on the other hand, overides this and lets fuel flow freely. Could I remove the vacuum hose from carb to petcock, cap the vacuum port at the carb, and run the petcock valve at PRI? would the carbs flood always? Can the bike be run like this?

I see some gunk in your carb man. It's time to give it a thorough cleaning (dipping). I've heard one of the best ways to clean the carbs, rubber and all, is to drop them in a pot of boiling water for about 15 minutes and then use WD-40 to get rid of all the water in all the passages along with some compressed air.

The issues you're describing are indicative of a sticking diaphragm.

I don't think it's worth replacing the petcocks - they either work or they don't as far as I understand it, and, most of what you're describing isn't pointing to the petcocks. Just my 2 cents though.

To clean the tank I would recommend a thorough sloshing to remove any sediment. You can use "B-12 Chemtool" and that should free up any kind of funk you've got growing in your tank. I know they make a specific product for cleaning fuel tanks but B-12 should be sufficient. It's about $3.99 for a pint.

Use your compressed air to blow back through the "tank mounted" petcock to clear the screen out.

Hello, and thanks for the reply. I'm boiling the carbs in lemon juice today. Regarding the stuck diaphragm, how can I tell if this is the problem? What would the solution be?

What ... you trying to make lemonade ?
DUDE CLEAN IT WITH TOOTHBRUSH - lemon juice has acids that will etch the aluminum.
Toothbrush and wd40 and gas is all I'd use on carbs.
Cool.
Buddha.

Quote from: vasama on December 27, 2011, 12:09:34 PM
Hello, and thanks for the reply. I'm boiling the carbs in lemon juice today. Regarding the stuck diaphragm, how can I tell if this is the problem? What would the solution be?

The lemon juice is unnecessary. If you must use something acidic, try a 1:10 dilution ratio with water and vinegar. However, keep in mind it's completely unnecessary to use anything acidic. The heat from boiling water and steam will be enough to clean them quite nicely. Alternatively, if you have some way of getting some steam going (like a Steam Shark) you can use that too. Just make sure you disassemble the carb after you expose it to water to make sure you have ALL of the water OUT before you go trying to run it.

Good luck.

Quote from: vasama on December 27, 2011, 12:09:34 PM
Regarding the stuck diaphragm, how can I tell if this is the problem? What would the solution be?

If your diaphragm is stuck, a simple removal of the top caps (the black ones) will tell you this. Carefully inspect them [the diaphragms] for any cracks or holes of any kind or if they look dried out. If there is any sign of wear you will need to replace them.

You'll have to take them off when you go to get the water from the boiling out of the carb anyway.

Acids<<< I KNOW!!! I said the same, but I read in several places of people swearing by the stuff. At the very least they talk about boiling water for about 10 min. Something about it going through all the passages and what not.
So, Buddah, now that I have your attention, after I clean the carb bodies, any product in particular that you'd recommend to clean the gas tank? Also, what's your take regarding the frame mounted fuel petcock... keep it or not?
Thanks

Quote from: vasama on December 27, 2011, 01:40:54 PM
Acids<<< I KNOW!!! I said the same, but I read in several places of people swearing by the stuff. At the very least they talk about boiling water for about 10 min. Something about it going through all the passages and what not.
So, Buddah, now that I have your attention, after I clean the carb bodies, any product in particular that you'd recommend to clean the gas tank? Also, what's your take regarding the frame mounted fuel petcock... keep it or not?
Thanks

I'm telling you man...don't put acid in the water. It'll make the aluminum all dusty and nasty and make it to where you have to clean it AGAIN. Lol. Boiling water is just as effective.

White vinegar will remove rust and steel BB's inside the tank should really dislodge all that mess. I don't know of any product specifically for cleaning gas tanks but the vinegar/steel BB combo worked wonders on my old dirtbike gas tank.

I have no idea how many miles your bike has done, but if it needed a freshen up I'm guessing it's a few.
I'd recommend replacing all jets and the float needle and seat. Jets are hard to effectively clean properly and wear out over time. They aren't really that expensive and you already have the carbs apart.
Then it's one less thing to go wrong. Good luck 

Quote from: mitch79 on December 28, 2011, 03:11:44 AM
I have no idea how many miles your bike has done, but if it needed a freshen up I'm guessing it's a few.
I'd recommend replacing all jets and the float needle and seat. Jets are hard to effectively clean properly and wear out over time. They aren't really that expensive and you already have the carbs apart.
Then it's one less thing to go wrong. Good luck 

I think he's determined to boil his carbs in lemon juice, dude. And apparently Buddha is the only person that knows how to clean carbs. 

Quote from: Kijona on December 28, 2011, 08:43:01 AM

Quote from: mitch79 on December 28, 2011, 03:11:44 AM
I have no idea how many miles your bike has done, but if it needed a freshen up I'm guessing it's a few.
I'd recommend replacing all jets and the float needle and seat. Jets are hard to effectively clean properly and wear out over time. They aren't really that expensive and you already have the carbs apart.
Then it's one less thing to go wrong. Good luck 

I think he's determined to boil his carbs in lemon juice, dude. And apparently Buddha is the only person that knows how to clean carbs. 

well, given the thread has suggestions that boiling in acid is a -good- idea... mmm hmm, might want to check out the buddha's skillset.

instead of boiling them ( wtf ? ) try pinesol. yes, plain old pinesol. give it two days in 100% pinesol, no boiling, chanting, or bludgening involved. if you don't believe me, toss a dirty bearing in it. you'll be amazed.

the high idle problem is likey a leaking intake boot, or lack of air cleaner, given the mess on the inside of the air passages. i'd bet on poor idle adjustment as a cause, and a partially clogged idle circuit.

whatever you do, DO NOT soak any of the pieces in carb cleaner. it kills rubber and melts some plastics. you've been warned !

Quote from: ohgood on December 28, 2011, 04:41:35 PM

Quote from: Kijona on December 28, 2011, 08:43:01 AM

Quote from: mitch79 on December 28, 2011, 03:11:44 AM
I have no idea how many miles your bike has done, but if it needed a freshen up I'm guessing it's a few.
I'd recommend replacing all jets and the float needle and seat. Jets are hard to effectively clean properly and wear out over time. They aren't really that expensive and you already have the carbs apart.
Then it's one less thing to go wrong. Good luck 

I think he's determined to boil his carbs in lemon juice, dude. And apparently Buddha is the only person that knows how to clean carbs. 

well, given the thread has suggestions that boiling in acid is a -good- idea... mmm hmm, might want to check out the buddha's skillset.

instead of boiling them ( wtf ? ) try pinesol. yes, plain old pinesol. give it two days in 100% pinesol, no boiling, chanting, or bludgening involved. if you don't believe me, toss a dirty bearing in it. you'll be amazed.

the high idle problem is likey a leaking intake boot, or lack of air cleaner, given the mess on the inside of the air passages. i'd bet on poor idle adjustment as a cause, and a partially clogged idle circuit.

whatever you do, DO NOT soak any of the pieces in carb cleaner. it kills rubber and melts some plastics. you've been warned !

Nah, I was just saying it didn't seem like he was listening to anyone but Buddha. :p

Boiling water isn't going to hurt your carbs...ever...unless you're silly enough to set the carbs down in the pan with the diaphragm covers facing the bottom of the pan. The only reason I suggested this is because it's the easiest and cheapest way to do it. It MAY or MAY NOT work, true, but it's the least risky. I'm not sold on Pinesol yet but maybe someday I will be. I'd be afraid of ruining my rubber.

Whatever you do, just be careful!

Hello, all

Away from the computer the last couple of days...

Please, I didn't mean like I wanted advice only from Buddah... Not at all! the only reason I asked him directly is because it seems like he has lots of experience with carbs, from reading some of his posts, and I was curious on his take. I apologize. I truly apreciate everyone's comments and suggestions.

I did put the carbs bodies in boiling water for about 10 minutes. A ring of grime was formed at water level on the pot I used. The carbs didn't come out squeakly clean, though. The outside was still a bit dirty, and some dark areas remained on the inside. I want to boil them again. Should it be longer? I'll also try the pinesol... For how long?

The bike has 11k miles on it.

As for a leak on the boots, I did a WD40 "leak test". No change in revs after spraying it all around the boots. I believe (and hope) that it'll be down to thorough cleaning, and perhaps valve adjustment. I'll be doing the steel bb's (what about pellets?) in vinegar tomorrow for the gas tank. I'll be cleaning the tank petcock with compressed air. The bike was rejetted about two months ago, following the recommendations in this site. The exhaust is stock. When I rejetted, I also changed the valve needles and their seats.

One of my original questions: Can anyone confirm whether or not this carbs have the emmissions circuit or not? The bike is a 2002 (2001, really) but its carbs are not what the Clymer book show. They're more like the previous model year.

Thanks again

If you have the PAIR emissions system you will have two approx 1/2" metal pipes connecting to the cylinder heads between the exhaust manifolds, although this shouldn't affect the running of the bike.

Continue as your doing, cleaning and checking.
If you have a tank full of crap it won't take much to block your new jets.
I'll add to the list check/replace your vacuum lines, float levels and accelerator cable. Make sure the cable isn't too tight, there should be just a little slack. This is so the throttle remains on the idle stop at full left/right deflection of the handle bars.
I'd also have a close look at the condition of the diaphragms. Should be soft and pliable with obviously no holes.

Here're the carbs immersed in pinesol. The bottles on the side are simply raising the pinesol level so it completely covers the carbs.

Quote from: vasama on December 30, 2011, 09:21:35 PM
Here're the carbs immersed in pinesol. The bottles on the side are simply raising the pinesol level so it completely covers the carbs.

[image deleted]

Let me know how that works man...I wanted to try this method but I was too scared. Hopefully you can tell us how it goes.

Quote from: vasama on December 29, 2011, 10:24:56 PM
Hello, all

Away from the computer the last couple of days...

Please, I didn't mean like I wanted advice only from Buddah... Not at all! the only reason I asked him directly is because it seems like he has lots of experience with carbs, from reading some of his posts, and I was curious on his take. I apologize. I truly apreciate everyone's comments and suggestions.

I did put the carbs bodies in boiling water for about 10 minutes. A ring of grime was formed at water level on the pot I used. The carbs didn't come out squeakly clean, though. The outside was still a bit dirty, and some dark areas remained on the inside. I want to boil them again. Should it be longer? I'll also try the pinesol... For how long?

The bike has 11k miles on it.

As for a leak on the boots, I did a WD40 "leak test". No change in revs after spraying it all around the boots. I believe (and hope) that it'll be down to thorough cleaning, and perhaps valve adjustment. I'll be doing the steel bb's (what about pellets?) in vinegar tomorrow for the gas tank. I'll be cleaning the tank petcock with compressed air. The bike was rejetted about two months ago, following the recommendations in this site. The exhaust is stock. When I rejetted, I also changed the valve needles and their seats.

One of my original questions: Can anyone confirm whether or not this carbs have the emmissions circuit or not? The bike is a 2002 (2001, really) but its carbs are not what the Clymer book show. They're more like the previous model year.

Thanks again

No problem. All in the name of helping a fellow rider!

I have no idea about emissions circuit but I can offer the following:
Steel BB's (I believe they're plated in nickel but you might luck up and find some stainless steel ones) are your best bet. They're ultra cheap at Wally World. I don't know if they make steel pellets but it seems unlikely. Plus, you get like 5lbs of BB's for the price of what you'd pay for one package of the pellets. Don't use the lead ones! Too soft. Also, DO NOT USE COPPER...obviously.

Step 1: Go to $1 Store and pick up two gallons of whatever vinegar they have (white is best because you can tell how dirty it gets, plus I think it's slightly stronger versus the others)
Step 2: Go to Walmart and pick up a big container of the silver BB's (I'd give you a link but I can't find them on wally world's site).
Step 3: Pour one gallon into the empty gas tank and slosh it around for about 5-10 minutes to ensure you get everything nice and saturated
Step 4: Let it sit over night (or 8hrs)
Step 5: Dump the whole container of BB's into the gas tank
Step 6: Start shaking/sloshing/whatever as long as you possibly can until you're tired.
Step 7: Take a break
Step 8: Repeat step 6. Be sure you turn it every which way and get those bb's really rolling in there.
Step 9: Drain that mucky mess out of there. Leave the BB's in for now.
Step 10: Add the second gallon of vinegar and repeat steps 6, 7, and 8.
Step 11: Drain everything. If it's still REALLY dirty at this point, you might want to rinse it a third time with the BB's. Note: will require more vinegar! You can re-use the BB's though. Just put them in a towel and clean them (use the "bowling ball polishing technique"...this will work nicely)
Step 12:  Add a gallon of your favorite, cheap gas and slosh it around AGAIN.
Step 13: Drain and give your lawn mower some "spiked" gas. 

Hope this helps!

Edit: For step 10 you could probably use half a gallon.  You decide!

Hello, and happy new year to all!

So, I'm ready to take the carbs out of the pinesol. What should I use to rinse them off? I'm thinking a second round of boiling water...?
I also left the tank soaking with a gallon of vinegar. I'm in the bb's stage right now. a couple more shakes and I'll rinse it.

Quote from: vasama on January 02, 2012, 01:29:48 PM
Hello, and happy new year to all!

So, I'm ready to take the carbs out of the pinesol. What should I use to rinse them off? I'm thinking a second round of boiling water...?
I also left the tank soaking with a gallon of vinegar. I'm in the bb's stage right now. a couple more shakes and I'll rinse it.

Perfect. Boil the carbs in water for about 10-15 minutes to make sure all the pinesol is gone and then you can spray the passages and everything with a generous amount of WD-40. (Hint: "WD-40" stands for 'Water Displacer - 40wt").

Pinsol SHOULD float to the top of the boiling water!