Roketa 250cc 54B Retired New Photos Added By speedracer (Read 2,970 times)

[yoster]

that orange fuel is the exact color fuel turns when it gets old. At the start of every boating season, that's the color of the leftover fuel in the gas tank in my boat.

You've probably already changed this, but do you know if the enrichener is working properly? That can have a dramatic effect on idle speed as you describe if it isn't functioning properly.

[speedracer]

Yoster, it is anything but cold here. A cool day is 78 this time of year, plus I ride the scooter or did ride the scooter daily. The enricher is fairly new.

[tvnacman]

speed two main things will affect idle , valves and carb . with that said you have screwed with the carb enough !!!! I know when I adjusted my valves I had to do it twice . About 1000 clicks later I feel it could start better and I plan to adjust the valves again , seeking improvement . I had carb problems I tried to clean it and adjust it bla bla... I bought a new carb problem solved .
The main problem I have found is the rubber in the carb is getting soft from the ethenoyl in the gas . I can't seem to find all the rubber pieces from one place at a price that is not the cost of a new carb .

there is great advice here , but you have to consider time verses new part cost .
John

[speedracer]

I certainly agree with you about time vs part cost. I am amazed how little attention the color of the gas received. Even the top names here except Alley said anything. Apparently I didn't know that gas changes color between the tank and the carb bowl. It must as NO one has said it remains clear. I posted 3 pictures and no expert has mentioned how it's not normal.

[tvnacman]

the color is a problem without a dought , something is causing that if it is comming from the pump , perhaps open it up and check it out .

John

[speedracer]

Earthman look at pics on page 1. Clear gas from filter and dirty gas from carb drain. I changed the pump back to the oem. I have drained carb bowl at least 10 times and still no clear gas from bowl.

[tvnacman]

Speed perhaps you should burn two tanks of gas give the old discolored gas a chance to clear.
Maybe the fuel pump is all gummed up get two gas cans some hose suck from one gas can dump into the other , suck on the vac port to get it going and look at the fresh fuel coming from the pump , perhaps 50/50 gas diesel mix will help clean out the pump , or destroy the pump . then flow 100% gas through the pump to clear the diesel and try again .
something is contaminating your fuel .
John

[speedracer]

John, I took the fuel pump apart today and there was nothing in it. Yesterday I put the OEM fuel pump on and changed the fuel hose as well. The gas is clean in the tank and through the fuel filter, pump, and now for sure the fuel hose to the carb.

The only thing I can come up with is that something in the gas coated the inside of the carb bowl and is changing the color of the gas. When I had the bowl off to re-clean the jets and passageways the bowl didn't look dirty at all. I have about a quarter of a tank of gas left, so tomorrow I will run it almost dry then fill it up.

What I would like to try is to remove the fuel line at the carb and open the drain on the carb bowl and spray carb cleaner in it. Does it sound safe to do? Not going to try running engine as I know it won't start with carb cleaner.

[speedracer]

Scooter has been at the Chinese scooter shop now for a week. The owner there has taken his time going over it and he is convienced the problem is the carb. He said there is no way to control the A/F mixture screw and throttle screw so that it idles at the same speed. He did a compression test which was fine. Every time he pulled the plug after making an adjustment and riding it the plug was white. He said he has changed 100's of carbs as they are just plain junk. He said if I wanted to order a carb and have it shipped to him, he would install for it me. So that's where it stands now.

[speedracer]

Last Friday the scooter shop called me and told me to come pick up my scooter as he has it running. He said he fixed the carb and did what he needed to get it back on the road. I never ordered a new carb thankfully. He replaced both diaphragms with new ones as a friend of his had those parts.

The A/F screw is set at 3 turns out. When I was there he asked me why I use an Iridium plug. I said I heard they are better. He just laughed and said this is not a Ducati or Super Bike. You are wasting your money when you can use a regular NGK plug.

Next he asked what gas I use. I told him regular unleaded. He said use 89 or 90 octane as it says in the manual. He said they do not use octane as a scale in China they use the Ron system so they are telling you the octane to use in the US. He said China uses 93 and 97 Ron so they would not have put 90 octane stickers on the scooter if they were using a Chinese system. He also mention that all of China switched to unleaded gas in 2000. Most cities before that. He moved here from China 4 years ago and was a foreman at a scooter factory.

Also since he had my scooter apart he looked at the variator and noticed I had Dr Pulley sliders in it. What he did was to take white lithium grease and slightly greased each slider with it and put them back in. I said they don't need grease as they are self lubricating. He laughed and said that's what Dr Pulley wants you to do, but the lithium grease will make them last longer and your variator will run effortlessly.

He said go start it up. First shot is started and no stall, and it sounded like there was no variator on the engine. I took it out for a test ride while it was cold and it ran smooth and fast. For the first time in a long time it was smooth and quiet. It has less then half a tank so I will run it down and then fill it up with 90 octane, and put my $2.00 NGK plug back in it.

[Cruiser]

Well, it's great to hear that you had a positive outcome with your visit to the scooter shop. Sounds like this guy might know what he's talking about. I use an Autolite 4194 in my scoot and am very happy with it. I also used a dry lubricant on my Dr. Pulley sliders. I put iridiums in my 2006 Street Cruiser because I didn't want to do it more than once while I own the vehicle.

[speedracer]

Cruiser thanks.... I was trying to make out what he was saying when he said China uses Ron. At first I thought he was talking about someone named Ron. Then it became clear when he said no octane in china only ron. Street cruiser is what he was talking about. I'm sure you can pull a lot of rpms with it.