I'm thinking fuel pump:

[richardthescooter1]

The other day at WOT my scoot shut off, even giving it a little gas in carb, would only run until it was used up, had my buddy haul it home, today started and its acting the same way. Now its dying when I'm trying to give it throttle, it idle good. I'm ready to put a electric pump on. What do you Dawgs think?

[spandi]

Did you try the Mikuni first?

[richardthescooter1]

That's what I have, been on the bike before I bought scoot, had scoot since feb of 2011 and I have over 15,000 mile on her. My main problem is at WOT, I read that at WOT vacuum is about 0, today as I rode anything over 50mph it starts choking, like its not getting gas.

[richardthescooter1]

Here is pump

[spandi]

15,000 miles? It might be time for one of these.

http://www.juniorspecialties.com/catalog/index.php?main_page=product_info&cPath=3_13&products_id=274

Didya also check your jets for gunk?

[smoak]

Are you sure it is a round mikuni and not a Chinese JinBo knock-off?

Mine is the same bike as yours, and it had a JinBo pump which started to fail on me. I just replaced it with the new rectangular genuine mikuni vac-pump, and it starts right up first hit now, and the motor idles a lot better.

I thought about going with an electric, but I worried about wiring it up. I have seen people wire them to something like the radio hot wire, which is only hot when the key is on.

My concern is that if I turn on the key and then have to step away for a moment that the always on electric pump will flood the carb... Or, do the elec pumps have built in safeguards against that?

Smoak

[richardthescooter1]

spandi, I've adjusted float, a/f, but I've never check or clean carb jets. smoak here is my pump

[smoak]

spandi, I've adjusted float, a/f, but I've never check or clean carb jets. smoak here is my pump
I don't think I have ever seen a Mikuni that looked quite like that!

I got my rectangle Mikuni on eBay for about $20 shipped. I don't know how much an electric costs, but it might be worth your while if they are expensive to pick up a $20 pump.. If nothing else you would have a good spare!

If you go electric, please let us know how you end up wiring it, and if it gives you flooding problems.:tup:

Smoak

[spandi]

The Mikuni I have is round. (nicknamed it "The Hockey Puck" after Don Rickles :D )

http://www.amazon.com/Mikuni-Fuel-Outlet-Round-DF52-176/dp/B000GZQ63E/ref=sr_1_7?ie=UTF8&qid=1371264711&sr=8-7&keywords=mikuni+round+fuel+pump

[richardthescooter1]

Hi spandi, yesterday JR suggested for me to check the ignition wire on my CDI in case that was the problem, last nigh I check it and it was loose, fix it and now nice and tight, today I'm going take carb off and clean all those jets, and I may still upgrade the fuel pump, the one you showed me, what is the capacity (gph)?

[spandi]

I found this from Mikuni. Although the DF52-176 isn't listed, I have no reason to think it would not be the same as the other round models, at 35 liters per hour or about 9 and a quarter gallons per hour U.S.

http://www.mikuni.com/c-fuel_pumps.html

P.S. just be sure whatever model you choose the nozzles line up with the way the hoses are going.

P.S. P.S. I was thinking maybe this is not just one particular thing going wrong, but maybe a series of small malfunctions happening at the same time, i.e. "The perfect storm" syndrome.

[richardthescooter1]

Well today I decided to take my carb off and check those jets, This is the first time I ever took the jets out, man were they clogged up, the main jets had maybe two open holes and the pilot jet only one, soaked them good and long and wire in the holes and cleaned the with carb spray and used my air nozzle to blow air through them, got carb back in and running, now I just have to put everything else back together and then the test drive.

[spandi]

Hope everything works out, even if it didn't cause the scoot to conk out going uphill, a gunked up carb couldn't have been a good thing. :no:

[richardthescooter1]

test drove scoot (yep shut off going up to 50mph,) got scoot back home after pushing her about a 1/4 mile, chech fuel line from tank to pump (gas is flowing good), took off pump and looked in side, as far as I could tell pump look ok), put back on and cranked, (no go) sprayed carb cleaner in intake line and scoot well start and runn for a few seconds, gas in fuel filter about a foot from carb. I think fuel pump.

[richardthescooter1]

I orderd fuel pump, should be here maybe today, will let you guys know how it goes.

[spandi]

Good luck with that, (I hope this solves the malfunction.)

[richardthescooter1]

Thanks, let you know how it goes.

[oldkid]

Fuel pump FYI. My 150cc would not run long at WOT when new because of lack of fuel. Sometimes I had to reduce to about 80% to get up the TN hills. I added a low pressure electric pump and pressure regulator and no more problems. Runs much better now. My pump only had power if switch is on. In addition I use a toggle switch to turn off pump when I want the carb. empty for storage.

[Guest_3]

Just a heads-up :) . You can get any Mikuni fuel pump or rebuild kit at most snowmobile shops. :tup:

[smoak]

did you order the electric pump? Let us know about the setup, as I am curious if it will flood the carb.

Smoak

[richardthescooter1]

Hi Smoak, I just went with the vacuum pump this time, its the DF44 Mikuni, test drove yesterday, got 60-65 easy, but climbing a big hill, it did choke twice but didn't shut off, I had my a/f set at 3 turns out, so last night I turn a 1/4 turn leaner to see if that helps.

[smoak]

Hi Smoak, I just went with the vacuum pump this time, its the DF44 Mikuni, test drove yesterday, got 60-65 easy, but climbing a big hill, it did choke twice but didn't shut off, I had my a/f set at 3 turns out, so last night I turn a 1/4 turn leaner to see if that helps.

That is exactly the one I put on mine. I was very happy with the pump, it made a huge difference in my startup. I haven't yet had the opportunity to get my bike in the 60's or 70's yet to see how it does... I guess I need too so I can see how it acts at higher speeds.

I am assuming that you have replaced the vacuum lines? A new strong pump like that might be collapsing weak vac lines.

Smoak

[richardthescooter1]

Well Smoak, That pump made a big difference. After turning the a/f 1/4 turn leaner last night made the difference, test drove the scoot today and she is running great, one more test tomorrow, going to work and climbing those hill, let you know how it goes.

[spandi]

Congratulations! Finally! :yay:

[richardthescooter1]

Took scoot to work today, and it ran great and I also conquered the hill.

[scootnwinn]

Awesome and yes finally