Fuel tap question and bike surging

[agentbad]

Okay so I just got my new petcock in the mail since the old one had a bad vacuum nipple that came out when doing simple maintenance. The screw on one side is missing the plastic washer that connects the tap to the gas tank. Should I order a new washer or just find the equivalent at lowes?

I had some surging issues maybe a month ago after the bike sat for about 10 days but was cleared up by some fresh gas so I just assumed it was water in the tank. The surging issues around 6000rpm are back so I've drained the tank completely and was considering just adding seafoam by itself at first just to make sure the carbs are clear. It sat for almost a month this time but I stabilized the fuel with seafoam. It will rev smooth in neutral past mid rpms but not when in gear. Could it be the idle/pilot jets even though I stabilized the fuel?

[Motofool]

Originally Posted by agentbad

................The screw on one side is missing the plastic washer that connects the tap to the gas tank..............Could it be the idle/pilot jets even though I stabilized the fuel?

There is a gasket between the petcock and the tank.

You added something to the fuel, but the fuel that remained in the bowls soon evaporated (the bowls breath to the atmosphere), leaving the non-volatile gunk behind.

It is not much, but enough to clog the very narrow passages of the jets.
Fresh fuel struggling to flow through those will dissolve that gunk, but it needs time while you will have precary engine performance.

The best preventive practice is running the bowls dry before any extended inactive time.

Rather than doing surgery, I would try going for a marginal 20 miles ride first.
Adding some Seafoam to the fuel would help.

[agentbad]

Here's the washer. The other side just had a ripped O-ring but it didn't leak as far as I know. These washers are supposed to be coated in something to protect them from gas. I'm wondering if I can just pickup a set somewhere local so I don't have to wait for partzilla to ship them to me since they forgot them.



Okay ill see if more riding and seafoam will clear things up.

[Motofool]

Originally Posted by agentbad

Here's the washer. The other side just had a ripped O-ring but it didn't leak as far as I know. These washers are supposed to be coated in something to protect them from gas. I'm wondering if I can just pickup a set somewhere local so I don't have to wait for partzilla to ship them to me since they forgot them.

I have never seen that washer.
Here you have some ideas for improvisation:
http://www.advrider.com/forums/showthread.php?t=627031

These materials are excellent to resist gasoline action:
Neoprene, Buna-N Nitrile, PVC, Neoflon®, Viton®, Fluorel®, Urethane and Nylon.

[agentbad]

Originally Posted by Motofool

I have never seen that washer.
Here you have some ideas for improvisation:
http://www.advrider.com/forums/showthread.php?t=627031

These materials are excellent to resist gasoline action:
Neoprene, Buna-N Nitrile, PVC, Neoflon®, Viton®, Fluorel®, Urethane and Nylon.

Thanks for link. That washer is the OEM washer and looks like it's just standard nylon. I am going to try and track one down.

Found the washer at lowes that's almost identical and nylon. Ran seafoam right into the fuel line and let run for a bit. Added some fresh gas then took it for a ride. Mid rpms are still not there so it looks like surgery on the carbs may be inevitable.

[FvnnyL3tt3r1ng]

I have yet to see seafoam do a darn thing other than on youtube videos.

I wouldn't be surprised if some crap got into your bowls. Check your fuel filter and flow rate if you want better peace of mind.

[agentbad]

Originally Posted by FvnnyL3tt3r1ng

I have yet to see seafoam do a darn thing other than on youtube videos.

I wouldn't be surprised if some crap got into your bowls. Check your fuel filter and flow rate if you want better peace of mind.

Well I just put a brand new petcock on the tank so I know it's getting fuel. What's a good way to check flow rate? The filter was clean when I checked it. Can I use guitar string to clean the tiny holes in the jets since I don't have an air compressor? How about a toothbrush? When adjusting the fuel/air mix screws is a turn like a 360 or 180. So two 360 turns and one 180 would be 2.5 turns out?

I'm tempted to buy another used set of carbs or just say screw it and go EFI.

[dcj13]

Originally Posted by FvnnyL3tt3r1ng

I have yet to see seafoam do a darn thing other than on youtube videos.

They've always been out of Seafoam at the auto parts store when I've looked for it, but the equavalent Gumout product has worked for me for "fixing" 2-cycle weedeaters, hedgetrimmers, and blowers. If a device was "put away wet" (last ran 2 or 3 years ago and stored with skanky gas), just fill tank with fresh gas with a capful of Seafoam or Gumout in the tank, get it running (barely) for about 5 minutes (combined starts, use ether starting fluid if you have to), twist any jet screws a turn each direction and put them back where they were, then let it set overnight. Chances are really good the next day it'll run as good as new.

Guys at the local watering hole actually think I do small motor repair for a living: good for many free beers.

[Motofool]

Originally Posted by agentbad

............Can I use guitar string to clean the tiny holes in the jets since I don't have an air compressor? How about a toothbrush? When adjusting the fuel/air mix screws is a turn like a 360 or 180. So two 360 turns and one 180 would be 2.5 turns out?.........

Avoid steel for cleaning brass jets.
One turn is 360 degrees.

All you want to know about your carbs is here:
http://faq.ninja250.org/wiki/Intake

Again, this is the rule of thumb: the problem usually is in the last thing that changed / the less you assume and change the less variables to drive you crazy.

[agentbad]

Originally Posted by Motofool

Avoid steel for cleaning brass jets.
One turn is 360 degrees.

All you want to know about your carbs is here:
http://faq.ninja250.org/wiki/Intake

Again, this is the rule of thumb: the problem usually is in the last thing that changed / the less you assume and change the less variables to drive you crazy.

Okay now I'm bit worried. Got the carbs off the bike and checked the jets. The mains and pilots look pretty good on both side. I'm giving them a little soak anyway but if it's not the jets then. I'm stumped.

Main jet threads seems to stick out a little is that normal. Threads look fine in the carb and on the jets just wanted to make sure.
http://i.imgur.com/cO5nEHU.jpg

[Motofool]

Originally Posted by agentbad

............Main jet threads seems to stick out a little is that normal............

It seems normal to me.
The thread that you see belongs to the emulsifier tube.



Please, read this:
http://www.ninjette.org/forums/showt...light=passages

[agentbad]

Fixed it! Cleaned the carbs as best I could then reattached everything and made sure everything was on tight. I got worried when the bowls took a second to fill up but they did. Took her for a spin around the neighborhood and holy **** the smile it put on my face. Smooth as silk. Laundry will have to wait.

[Motofool]

Originally Posted by agentbad

Fixed it!.............Took her for a spin around the neighborhood and holy **** the smile it put on my face. Smooth as silk. Laundry will have to wait.

[dcj13]

Originally Posted by agentbad

Took her for a spin around the neighborhood and holy **** the smile it put on my face. Smooth as silk. Laundry will have to wait.

Cool! And congratulations! It feels really good to accomplish something like you did!

But get the laundry going. You can ride while the washer (and/or dryer) is doing the work.

[agentbad]

Okay another small issue this morning. It was a bit cold out so I turned the choke on and let the bike warm up for a bit. As I was throwing on my gear the bike suddenly stalled. I was able to get it going again by giving it throttle. On the way to work it kept trying to stall at lights but staying on the throttle again kept it running. Once I got on the highway I left the choke on to maybe clear out what was ever causing the issue and once I got to work it would idle fine without choke. The enricher circuit was actually clean when I pulled the carbs so I'm a bit baffled what's going on. Right now the idle screws are 2.5 turns out so should I try 3 turns out since I run 112 mains and 40 pilots? Bike is running great otherwise.

[jkv45]

Originally Posted by agentbad

Okay another small issue this morning. It was a bit cold out so I turned the choke on and let the bike warm up for a bit. As I was throwing on my gear the bike suddenly stalled. I was able to get it going again by giving it throttle. On the way to work it kept trying to stall at lights but staying on the throttle again kept it running. Once I got on the highway I left the choke on to maybe clear out what was ever causing the issue and once I got to work it would idle fine without choke. The enricher circuit was actually clean when I pulled the carbs so I'm a bit baffled what's going on. Right now the idle screws are 2.5 turns out so should I try 3 turns out since I run 112 mains and 40 pilots? Bike is running great otherwise.

What was the air temp? I would try going out to 3 turns and see how it acts. If it's worse, go down to 2 turns out.

Idle speed is 1300 hot? Gas is fresh and tank is kept pretty full most of the time?

[agentbad]

Originally Posted by jkv45

What was the air temp? I would try going out to 3 turns and see how it acts. If it's worse, go down to 2 turns out.

Idle speed is 1300 hot? Gas is fresh and tank is kept pretty full most of the time?

Fresh tank with new petcock. Temp was about 41 this morning.

[jkv45]

Originally Posted by agentbad

Fresh tank with new petcock. Temp was about 41 this morning.

What was the temp last time you made adjustments?

Are you running ethanol-free gas?

[agentbad]

Originally Posted by jkv45

What was the temp last time you made adjustments?

Are you running ethanol-free gas?

65ish yesterday when I cleaned the carbs and adjusted the idle mix. Gas has ethanol in it.

[jkv45]

Originally Posted by agentbad

65ish yesterday when I cleaned the carbs and adjusted the idle mix. Gas has ethanol in it.

If you can get gas without ethanol you may not need to make any adjustments. Ethanol in gas will lean the mixture in a bike with carbs, as will cold air. Just going to ethanol-free could richen it up enough to make it run better in cold temps, but it would be rich when it got warmer - so you'd need to make an adjustment then.

Overall it's a good idea to stay away from ethanol in gas if you can. A completely stock cycle will probably run better (slightly richer) with ethanol-free gas. One that has been tuned properly for gas with ethanol might need slight tuning when going to ethanol-free.

[agentbad]

Originally Posted by jkv45

If you can get gas without ethanol you may not need to make any adjustments. Ethanol in gas will lean the mixture in a bike with carbs, as will cold air. Just going to ethanol-free could richen it up enough to make it run better in cold temps, but it would be rich when it got warmer - so you'd need to make an adjustment then.

Overall it's a good idea to stay away from ethanol in gas if you can. A completely stock cycle will probably run better (slightly richer) with ethanol-free gas. One that has been tuned properly for gas with ethanol might need slight tuning when going to ethanol-free.

Unfortunately the only place close to me that has ethanol free gas is a boat ramp.

[Yarhj]

Originally Posted by agentbad

Okay another small issue this morning. It was a bit cold out so I turned the choke on and let the bike warm up for a bit. As I was throwing on my gear the bike suddenly stalled. I was able to get it going again by giving it throttle. On the way to work it kept trying to stall at lights but staying on the throttle again kept it running. Once I got on the highway I left the choke on to maybe clear out what was ever causing the issue and once I got to work it would idle fine without choke. The enricher circuit was actually clean when I pulled the carbs so I'm a bit baffled what's going on. Right now the idle screws are 2.5 turns out so should I try 3 turns out since I run 112 mains and 40 pilots? Bike is running great otherwise.

My bike is similar, in that it's pretty finicky when it's just been started, and won't idle happily until it's warmed up a bit, even with the choke on. I don't think the issue is the enricher/choke circuit here -- it's more likely the idle circuit, and the bike may just be stalling early on because with the choke on it's getting too much fuel and not enough air. The easy way to test this out is to get it started, and then fiddle with the choke once it's running -- if you partially close the choke (or crack the throttle), do the revs increase, or does it try to stall? If the revs climb, then the mixture is just too rich with the choke fully engaged (which isn't really an issue, since that's the whole point of the choke).

In my case the problem is mostly my fault, as my bike tends to sit during the week since I carpool to work, and the pilot jets and idle circuit really don't enjoy that. If I leave the choke fully engaged when I start out, it tries to either surge or die depending on the temperature. My fix is to just get my gear on first, start it up with the choke and ride off sedately, turn off the choke, and keep it alive at the first few lights with very light throttle. After a few minutes of riding it will idle happily. It's not the most satisfactory solution, but it works well enough.

[harvey58]

Surging in the 6-8k range during colder temps is not an issue that can be solved with an idle mixture adjustment. This is a function of the metering needle in the throttle slide. I noticed this happening when temps got below 50 degrees or so. Some good info can be found here.
http://www.factorypro.com/tech/tech_...m_engines.html
And here.
http://faq.ninja250.org/wiki/How_to_...e_your_jetting
Also, when "going through" your carbs replace the inlet needles and set the float levels CORRECTLY! A simple "upside down" float setting will get you close, but not fully accurate. Float levels must be checked "wet" with fuel in the bowls, carbs off the bike in some sort of stand with an external fuel supply. Pain in the butt, but worth the effort considering what it takes to remove and reinstall the carbs.
Regarding inlet needles (float valves), the OEM parts are about $35 each. K&L parts 18-8953 (Needles, 6 pack), 18-2676 (Bowl Gaskets, 4 pack) can be found at
http://www.mcmcycleparts.com/store/
for less than the cost of 2 inlet needles.
The reason for replacing the needles is that the dampening spring in the needle gets weak over time.
Also, go to Ebay and look for the service manual on CD for your bike. This will show you how to properly set the fuel level in the carbs.

[agentbad]

Originally Posted by Yarhj

My bike is similar, in that it's pretty finicky when it's just been started, and won't idle happily until it's warmed up a bit, even with the choke on. I don't think the issue is the enricher/choke circuit here -- it's more likely the idle circuit, and the bike may just be stalling early on because with the choke on it's getting too much fuel and not enough air. The easy way to test this out is to get it started, and then fiddle with the choke once it's running -- if you partially close the choke (or crack the throttle), do the revs increase, or does it try to stall? If the revs climb, then the mixture is just too rich with the choke fully engaged (which isn't really an issue, since that's the whole point of the choke).

In my case the problem is mostly my fault, as my bike tends to sit during the week since I carpool to work, and the pilot jets and idle circuit really don't enjoy that. If I leave the choke fully engaged when I start out, it tries to either surge or die depending on the temperature. My fix is to just get my gear on first, start it up with the choke and ride off sedately, turn off the choke, and keep it alive at the first few lights with very light throttle. After a few minutes of riding it will idle happily. It's not the most satisfactory solution, but it works well enough.

I ride pretty much all the time when the weather isn't below 40 but the recent cold snap had my bike sitting for almost a month hence the carb cleaning. It runs like a champ once it's warmed up so maybe I will give the idle screws another go and richen up the mix a little bit more. That's a good point about the choke maybe I used to much after the adjustment and it wasn't getting enough air or maybe it got flooded.

Originally Posted by harvey58

Surging in the 6-8k range during colder temps is not an issue that can be solved with an idle mixture adjustment. This is a function of the metering needle in the throttle slide. I noticed this happening when temps got below 50 degrees or so. Some good info can be found here.
http://www.factorypro.com/tech/tech_...m_engines.html
And here.
http://faq.ninja250.org/wiki/How_to_...e_your_jetting
Also, when "going through" your carbs replace the inlet needles and set the float levels CORRECTLY! A simple "upside down" float setting will get you close, but not fully accurate. Float levels must be checked "wet" with fuel in the bowls, carbs off the bike in some sort of stand with an external fuel supply. Pain in the butt, but worth the effort considering what it takes to remove and reinstall the carbs.
Regarding inlet needles (float valves), the OEM parts are about $35 each. K&L parts 18-8953 (Needles, 6 pack), 18-2676 (Bowl Gaskets, 4 pack) can be found at
http://www.mcmcycleparts.com/store/
for less than the cost of 2 inlet needles.
The reason for replacing the needles is that the dampening spring in the needle gets weak over time.
Also, go to Ebay and look for the service manual on CD for your bike. This will show you how to properly set the fuel level in the carbs.

I'm not having any trouble with surging now that the carbs are clean so I think the needle height and floats are good.