Spree - Slow Take Off AFTER engine warms up

[Christophertemple]

84 Spree, original pulleys with shim/washer in front behind pulley, brand new OEM belt. Rear Gear Oil Recently Changed, Clutch pads looked glossy so I sanded them down, 1,100 miles on scooter.

Runs great for about 10 minutes but once the engine/variators warm up, I can barely take off, if I can get it to about 10-15 mph it will take off fine and run perfect. Come to a stop and take off again, barely will go like the belt is not slipping enough in the pulleys.

Once it cools, runs fine for a while. When it isnt taking off, I can lift the rear wheel and twist the throttle and it revs right up and spins the tire fine, but if I sit on it, issues. I am only 170lbs

[motormike]

My first inclination is to suspect the bystarter.
If it is not shutting the cold-start enrichment circuit OFF after warming,
then the fuel mixture will be very rich and give problems as you describe.

[motormike]

Since you don't relate to scooter terms yet, newb...
The bystarter is a thermo-reactive valve that controls the "choke" system on the carburetor.
It has two wires, two screws holding it on, with a horseshoe retainer.
it can be tested with an Ohm-meter.
The service manual gives the value, not sure what that is.

[Christophertemple]

I put a new carb and bystarter on the bike since my last post. Did not fix the problem... .It feels like the belt isnt slipping enough to take off, like its stuck in high gear ( I know thats not a thing)

[Wheelman-111]

Greetings:

You may be under a misapprehension. The belt is designed NOT to slip, although it does incrementally under high loads at speed. That's why there's a big strong spring squeezing the belt between the rear pulleys, and jamming it into the wedge formed by the front pulleys. All the Slip happens at the clutch, which is the bell-shaped assembly on the end of the driven shaft. If the clutch pads are glazed or excessively worn, your take-off will suffer. Likewise if the belt is old, and worn-out, it WILL slip and symptoms will be similar. You reported having addressed some of this with a new belt. If that SHIM WASHER is preventing the front pulleys from gripping the belt- if the pulleys are too far apart - that may be the problem.

[jranilovich]

Since you don't relate to scooter terms yet, newb...
The bystarter is a thermo-reactive valve that controls the "choke" system on the carburetor.
It has two wires, two screws holding it on, with a horseshoe retainer.
it can be tested with an Ohm-meter.
The service manual gives the value, not sure what that is.

MotoMike, i am having the same issue, what do you think is going on if the bystarter test out ok??

My bystarter test good ohm wise.

[Sleepysspree]

Any results/ fixes?