Problems with Solana 49cc

[wickedboy6]

I've recently been having some major issues with my 2023 Solana 49CC scooter. A couple weeks ago, it was running fine, but lately, I've been noticing a lot of strange issues. It takes a while to start up in the mornings, it won't accelerate like it used to, and usually tops at 10MPH for a while. It feels like when it accelerates, something is pulling back on it, either keeping it at 10, or even decelerating it down. It dies at idle. After some time, the top speed goes up to 12, 15, 18, 21 MPH, hovers around there, but sometimes, it'll drop back down for a while, only to slowly creep back up. And a couple months ago, I was able to take her past 35MPH no problems.

Roommate and I have done a few upkeep troubleshoots to see if anything was the issue. New gear belt, cleaning air filter, oil change, gear oil change, new spark plug, nothing's worked. We're thinking of changing to a 3/16" fuel filter, but beyond that, I have no idea what's going on. It's got 1300 miles on it, Just got it earlier in the year in April, and it had been in one accident with a pothole that jammed the front end a bit, but it still ran fine. These problems are all new, only starting a couple weeks ago.

[aeroxbud]

These little bikes are prone to getting the small jets in the carb blocked. That would be my first port of call.
Make sure the accelerator pump is functioning correctly.

[wickedboy6]

Well, my roommate helped me clean the carb and the hoses, even had Seafoam poured into the tank, and...

...no improvements. Well, one improvement. It doesn't lurch on acceleration anymore. It still has a hard time getting up to speed, it maxes at 10mph when at full throttle, and only increases as ridetime goes on, dies at idle when at a red light. I have a 3/16" fuel filter coming in next week, going to try that.

[geoffh]

Unless the filter is blocked the new one won,t help,whilst the carb is fairly simple it is prone to causing problems,you need to clean it again and ensure that not only are the jets clear but all the passage ways are clear,this is not as easy as it sounds,I submerge each half in water and blow air through each one,a sonic cleaner was on my Christmas list!!.

Geoff

[GrumpyUnk]

What he said.
To clean successfully you must remove the pilot and main jets and insure they are clear(you can see a pinpoint of light thru the pilot). You also may want to gently seat the idle mixture adjustment screw, counting the turns, remove it fully and clean out the insides. You can squirt cleaner backwards from the venturi into the idle outlet ports(tiny holes in the wall of the venturi) while the jets and mixture screw are removed. Re-assemble, making sure you have the O-ring, washer on the mixture screw. Run it gently to the hard stop, and back out the number you remembered from before. Make sure the float bowl valve is clear and moves easily. Invert the carb and blow through the fuel feed. The float valve should block your breath, and if not, you will get a flooded carb. PBT and see how it works.
tom

[wickedboy6]

The carbs were cleaned very well. Even use B'laster on them. Fuel filter was installed, and things seemingly got worse. I feel like no matter what is done, it gets worse. Today, the starter just refused to kick over after my roommate poured a bit of 108 Octane into it, as well, but nothing seems to take. Now, it longer seems to start. I want to try the battery again, but is there anything else it could be, if not the carb?

[GrumpyUnk]

I would check that you have good fuel supply. Disconnect the fuel line at the carburetor inlet. Prepare a catch can/jar, whatever, to receive fuel. Disconnect the vacuum line at the intake elbow that connects to the vacuum operated petcock. Apply suction while holding the fuel line over the catch can. As suction opens the valve, fuel should flow from the fuel line. The flow should be the full diameter of the fuel line, no dribbling, a full flow. If not, check the fuel filter, the fuel line itself(internal damage due to disintegration) and the inlet screen to the petcock inside the fuel tank. The petcock should also be considered if you find nothing else impeding flow.
If you get full diameter fuel flow, and it won't run past 10mph, you may have a sticking float valve. You have cleaned... did you check that the float valve flows by blowing air through it while holding the carburetor upside down? It should flow as long as you hold the float up a bit, but block airflow as soon as you let the float weight close the float valve. The float should be about parallel to the venturi when it is held upside down and allowed to press on the needle. The float bowl surface is angled, so the check is done roughly parallel to the carb being held horizontal.
Check also that the slide inside can move freely, and that the slide diaphragm is properly positioned under the cover. There should be a 'tab' that fits into a machined recess on the top of the carb to determine proper slide alignment in the bore. Well for sure it determines diaphragm alignment... And the diaphragm should allow free movedment of the slide when picked up inside the venturi with a handy finger. The slide should make noise as it is lifted and allowed to drop. The noise of air being inhaled/exhaled by the diaphragm...
tom