85 Spree dies on hard acceleration

[Meatball]

I just picked up an unmolested 85 Spree from a little old lady with all original parts. Its real clean and everything works but it struggles upon acceleration. Up on the stand it revs just fine when I "blip" the throttle. Sounds healthy all the way up the RPM range. Different story when I ride it. When climbing in speed, it struggles if I give it too much gas to the point where it dies. It will VERY slowly get to 25mph if I "feather" the throttle and baby it. I know Sprees don't accelerate quickly anyway but it shouldn't take an entire city block to get to 25mph. Its like I have to start off at 1/4 throttle until it reaches 10mph and inch my way up as it accelerates. If I give it too much gas too quickly, I hear the engine bog down and I have to let off a bit or it will die. The scoot has about 3600mi on it and I don't know the service history since the previous owner knew nothing. Does this sound like a typical carbon cake muffler or something else? Im new to Sprees so please keep the responses remedial...

[tazland001]

Have you cleaned the carb and air filter. Sound like you might need to service it a bit. How long did it sit for?

taz

[Meatball]

Previous owner claims she rode it all the time around town and the "throttle feathering" has been like that for a long time. Is there a decent write-up on carb cleaning for these? The couple youtube videos I watched were done by complete idiots. One guy even used a swiss army knife to remove some screws since he didn't have a proper screwdriver.

[tazland001]

lol omg that was funny. A swiss army knife. Im on my way to work but if you look thru the threads you will find out how to do it right. Compressed air and carb cleaner is the ticket. Wish i had more time.

Taz

[eclark5483]

Yeah, I saw that Swiss army knife video a few months ago. I about died from laughing. Totally NOT a guy I would want working on my scooters or motorcycle.

EDIT, here is a link to that video and what NOT to do.

http://www.youtube.com/watch?v=fH__An3ZDYo

[patthesoundguy]

Sounds like one of few things... clogged orifice for the idle air circuit. Or improper idle air mixture or both. Check the air filter as Taz mentioned. If there is an air leak in the airbox lid or hose to the carb it will be lean and act like that as well. With the motor warmed up follow the service manual procedure for setting the idle air mixture and idle speed. See if the bottom end improves. The idle air mixture is responsible for the first 1/4 throttle so that could be your issue.

[Meatball]

After cleaning the carb, testing the petcock for proper operation, draining/cleaning the fuel tank and fill with fresh gas, checking/cleaning/oiling the air filter and replacing the spark plug...it STILL choked on WOT after 15mph. Then I started playing with the fuel mixture. While running on the stand, I turned the mixture screw counter clockwise until it started to die, then turned up the idle screw to compensate. Then did this process a bit more. Once I went too far the scoot started to smoke so I backed off. I found a happy spot with mixture and idle and the spree is a screamer!!! She pulls smooth at WOT all the way to about 27-29mph. Thanks for all the help, guys! I used a few of your threads to help with my questions. If you live in the area, come by and lets ride!

[Meatball]

Heres another noob question...Why are there holes drilled in the top of my air box? They don't look factory and just doesn't seem right. Was this someones attempt to add performance by increasing airflow and turning the fuel way up? By the way, I covered the holes with duct tape during my maintenance overhaul today. That may have helped contribute to my success. Any thoughts?

[patthesoundguy]

Those holes were likely your problem You got this, you won't be a noob for long. Turning the mixture screw in gives more fuel on idle and launch, turning it out gives less fuel. Actually it there is a preset amount of fuel the screw meters thaw amount of air to mix with the preset amount of fuel. The holes in the airbox made your motor run extremely lean causing the bogging. Good thing you found the problem, you were on your way to having a seized cylinder. And yes it was likely an attempt to gain performance, and as you found did nothing but hinder it. A stock spree motor needs to be the way it came with the airbox intact.

[tazland001]

Ahh meatball you got it. Winner winner. Pat is correct the holes were prob the problem. My american bulldogs name is meatball. lol

Im sure the carb cleaning was needed also.

Taz

[Meatball]

My late great Bully's name was Meatball so naturally that's my online handle for everything..lol..I was riding the Spree around town today and actually got "the wave" from a guy on a crotch rocket...almost fell off the scoot with laughter! HA! Thanks again for all the help, guys.