Author Topic: [SOLVED] problem when accelerating from a stop  (Read 5815 times)

lukasbasic

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[SOLVED] problem when accelerating from a stop
« on: July 01, 2014, 02:20:12 PM »
what are the common things to check/service?
the scooter does have an delayed acceleration, like something is holding its back. once you give full throttle it will rush abruptly forward and at some point drive normally.
it is just the initial acceleration from a stop.
« Last Edit: July 11, 2014, 02:25:41 PM by lukasbasic »

DMblues01

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Re: problem when accelerating from a stop
« Reply #1 on: July 01, 2014, 02:59:06 PM »
How much throttle are you giving it when taking off?
It has to hit a certain rpm before the cvt opens up and grabs. I have to give it about half throttle to take of normal. Anything less and it moves like a snail.

Also, is it new or old? If it's got some miles on it, have you had the cvt serviced at any point for normal wear?
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BettinANDlosing

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Re: problem when accelerating from a stop
« Reply #2 on: July 01, 2014, 03:45:47 PM »
Sounds like the idle circuit in the carb could be plugged too.
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DMblues01

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Re: problem when accelerating from a stop
« Reply #3 on: July 01, 2014, 03:55:19 PM »
Sounds like the idle circuit in the carb could be plugged too.

Yeah, I didn't think of a possible carb issue. Worth checking though! Just to be sure.
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lukasbasic

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Re: problem when accelerating from a stop
« Reply #4 on: July 01, 2014, 05:55:06 PM »
so clean the carb? this is happening when i give max throttle from a stop

How much throttle are you giving it when taking off?
It has to hit a certain rpm before the cvt opens up and grabs. I have to give it about half throttle to take of normal. Anything less and it moves like a snail.

Also, is it new or old? If it's got some miles on it, have you had the cvt serviced at any point for normal wear?

lukasbasic

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Re: problem when accelerating from a stop
« Reply #5 on: July 01, 2014, 05:57:03 PM »
scooter has 4500 miles. carb was never cleaned nor the spark plugs. transmission, valves and gear oil done at specified intervals

How much throttle are you giving it when taking off?
It has to hit a certain rpm before the cvt opens up and grabs. I have to give it about half throttle to take of normal. Anything less and it moves like a snail.

Also, is it new or old? If it's got some miles on it, have you had the cvt serviced at any point for normal wear?

DMblues01

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Re: problem when accelerating from a stop
« Reply #6 on: July 01, 2014, 06:42:02 PM »
If the spark plug hasn't been touched in 4500 miles, change it. See if it makes a difference.
I changed mine after 1000 miles because it fowled.
Carquest and O'Reilly's Auto Parts has NGK CR7HSA plugs for about $2.30. Cheap insurance to change it on a regular basis.
Also, put about an ounce of Seafoam in the gas and see if it helps. Otherwise, open the carb and clean all the jets.

so clean the carb? this is happening when i give max throttle from a stop


If it's doing it at max throttle, check that your auto choke is working right. If it's not closing, it could be flooding the carb out.
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lukasbasic

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Re: problem when accelerating from a stop
« Reply #7 on: July 02, 2014, 05:30:02 PM »
SEAFOAM did seem to help! thanks a lot for the tip, also got a 2usd spark plug from oreilly today and ordered some air filter
do you got any ideas why my top end is lower then it is used to be, i barely seem to make 50mph where it used to be 55-60mph (i know that the speed display adds 5mph or so anyways)


If the spark plug hasn't been touched in 4500 miles, change it. See if it makes a difference.
I changed mine after 1000 miles because it fowled.
Carquest and O'Reilly's Auto Parts has NGK CR7HSA plugs for about $2.30. Cheap insurance to change it on a regular basis.
Also, put about an ounce of Seafoam in the gas and see if it helps. Otherwise, open the carb and clean all the jets.

If it's doing it at max throttle, check that your auto choke is working right. If it's not closing, it could be flooding the carb out.

DMblues01

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Re: problem when accelerating from a stop
« Reply #8 on: July 02, 2014, 09:03:19 PM »
do you got any ideas why my top end is lower then it is used to be, i barely seem to make 50mph where it used to be 55-60mph (i know that the speed display adds 5mph or so anyways)

Could still just be from the carb gunked up. You may still need to open it up to fully clean the jets.
You may also check if there is excessive play in the throttle cable. The throttle shouldn't have more than about 10mm of play before the cable moves. If it has a lot of play, you might not be getting all your throttle.
Use the search function on here and type in throttle cable adjustment. Wkreps uploaded a great video of how to adjust the play in the throttle cable.
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PeTroL42

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Re: problem when accelerating from a stop
« Reply #9 on: July 05, 2014, 06:44:43 PM »
Do you live at sea level or close to sea level?

If so, it might be due to the air/fuel mixture screw needing to be adjusted. 

Due to emissions standards, the Super 8s come from the factory with the air/fuel ratio on the low side.  I live close to the beach and when I first got my Super 8, it would hesitate to accelerate from a stop just as you're describing. 

I turned out the air/fuel mixture screw and this helped out the situation a lot.  The only problem is that the air/fuel mixture screw is under a metal cap that you have to drill out or if you're lucky, you'll be able to use a small flat head screwdriver and pry the cap off.  And then you'll find that the screw doesn't have a slot to insert a screwdriver so you'll have to use some really fine needle nose pliers to turn the screw counter-clockwise. 

Also,you might need to re-jet as well as the stock main jet is a tiny 103 size but I would try turning out the air/fuel screw first as it doesn't cost you anything to do.

lukasbasic

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Re: problem when accelerating from a stop
« Reply #10 on: July 07, 2014, 08:48:55 PM »
yeah, i live within 2 miles of L.A. coast
this thing appeared recently though after 2 years of service, and seafoam helped so far did not have problem
thanks for tip going to fall to the mixture as a last resort

Do you live at sea level or close to sea level?

If so, it might be due to the air/fuel mixture screw needing to be adjusted. 

Due to emissions standards, the Super 8s come from the factory with the air/fuel ratio on the low side.  I live close to the beach and when I first got my Super 8, it would hesitate to accelerate from a stop just as you're describing. 

I turned out the air/fuel mixture screw and this helped out the situation a lot.  The only problem is that the air/fuel mixture screw is under a metal cap that you have to drill out or if you're lucky, you'll be able to use a small flat head screwdriver and pry the cap off.  And then you'll find that the screw doesn't have a slot to insert a screwdriver so you'll have to use some really fine needle nose pliers to turn the screw counter-clockwise. 

Also,you might need to re-jet as well as the stock main jet is a tiny 103 size but I would try turning out the air/fuel screw first as it doesn't cost you anything to do.

DMblues01

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Re: problem when accelerating from a stop
« Reply #11 on: July 08, 2014, 07:41:37 AM »
yeah, i live within 2 miles of L.A. coast
this thing appeared recently though after 2 years of service, and seafoam helped so far did not have problem
thanks for tip going to fall to the mixture as a last resort

I run an ounce of Seafoam about every third or fourth fill up, to keep from getting build up in the carb.
If it has any more issues, you may also want to change the fuel filter to make sure it's flowing properly.
Also,if you have a high ethanol percentage in California (10% or higher), you might want to use an ethanol treatment from time to time.
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lukasbasic

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Re: problem when accelerating from a stop
« Reply #12 on: July 11, 2014, 02:53:19 AM »
installed racing spark plug, adjusted throttle free play, replaced air filter
and scooter runs like new or better! I can't believe the difference in agility, especially for city traffic
got my 5mph back at top end, altough this is not really of importance for that type of cycle

thanks a lot for help and greeting from L.A.

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