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Scooters - 50cc => Super 9 => Topic started by: mroc on May 10, 2015, 02:17:35 PM

Title: SLOW TAKE OFF
Post by: mroc on May 10, 2015, 02:17:35 PM
MY NINE all of sudden is boggingdown off line and not revving up to gear . revs hanging in 5000-6000 range. I thought it was cvt issue so swapped belt clutch and bell . it did improve 10% but still not good. now it picks up but very extended and long. I am thinking of checking autobystander would this be the logicial next step? bike was ripping a few days ago. gotta fix today daily rider. stock except for aftermarket pipe and upjet to 95
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 10, 2015, 02:27:37 PM
Did you check out your variator while you were in there?  I was breaking the clips on the back plate at one point.  And I ruined a boss drive at one point,  it would stick at takeoff and deceleration. 
I'm not sure how the auto bystarter would cause that,  but I'm no pro,  ha ha.
Title: Re: SLOW TAKE OFF
Post by: mroc on May 10, 2015, 02:38:08 PM
Just replaced the clips which are called vee bushings clips ruled that out but thanks.
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 10, 2015, 02:43:01 PM
Does it only do it under a load,  not while on the stand? 
Title: Re: SLOW TAKE OFF
Post by: mroc on May 10, 2015, 03:00:37 PM
Yes under load
Title: Re: SLOW TAKE OFF
Post by: mroc on May 10, 2015, 03:01:28 PM
Worsen when engine warms up
Title: Re: SLOW TAKE OFF
Post by: mroc on May 10, 2015, 03:10:57 PM
It's struggling to hit 7000 rpm
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 10, 2015, 03:33:51 PM
Compression check yet?
Title: Re: SLOW TAKE OFF
Post by: mroc on May 10, 2015, 07:01:01 PM
Yes 90psi on auto start
Title: Re: SLOW TAKE OFF
Post by: mroc on May 10, 2015, 07:08:44 PM
Plug very light brown with white inside plug chop area. Also swapped vario for another same issue
Title: Re: SLOW TAKE OFF
Post by: chaz35 on May 11, 2015, 03:54:39 AM
Auto bystarter is choke, so if not working would cause engine to be too rich, run lousy.  I think 90psi is low compression.  Manual says 11.8 kg/cm2 which is approx 167psi.  I can't find it, but recall min is approx 120 to 140psi.
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 11, 2015, 06:51:06 PM
I ran mine with 90 psi just fine for a while,  everyone swore that was the lowest it would run.  Was that warm or cold? 
I've heard horror stories of the crank seals going out on these.  I think that would cause case compression loss after being warm.  Have you got the tools to do a leak down test?
Is personally would dodge that,  just just because I wouldn't want to know.  I would be cleaning the carb,  everything down to plug wire.  Actually,  just a wild shot,  have you trimmed the ends of your plug wire?  I chased around all issue not long after getting mine,  did everything,  just to find that the ends of my wire were very worn. 
Probably not it,  but I'm just grasping at straws.
Title: Re: SLOW TAKE OFF
Post by: chaz35 on May 12, 2015, 02:16:25 AM
How many miles/ kilometers?  I think B&L is right, need to check all the easy stuff 1st, make sure not something easy to fix.  I guess would be a pretty big project to replace the crankseals, have to pull the stator on 1 side and the variator on the other.  Seems like I saw some oversized pistons on ebay or somewhere, so could put in another piston easy enough (would be a big job for me).  Does Kymco make oversized pistons?
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 14, 2015, 03:23:14 PM
That would be a 70cckit, the most popular.  I've put one on mine.  Not too hard. 
Title: Re: SLOW TAKE OFF
Post by: chaz35 on May 15, 2015, 04:42:42 AM
Tries, I am talking about 50cc engine, keeping it that way with new oversized piston/ rings.  Take the cylinder and new oversized piston to engine building that knows how to fit the piston, then put it all back together.  If done right, should run like new and be a lot less $'s.

http://www.ebay.com/itm/Kymco-People-50-2T-2000-2002-Meteor-Piston-Kit-1-Oversize-/301475658400?pt=LH_DefaultDomain_3&hash=item4631597aa0&vxp=mtr#shpCntId (http://www.ebay.com/itm/Kymco-People-50-2T-2000-2002-Meteor-Piston-Kit-1-Oversize-/301475658400?pt=LH_DefaultDomain_3&hash=item4631597aa0&vxp=mtr#shpCntId)
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 15, 2015, 10:39:10 PM
I see,  just .2mm larger.  I suppose it would retain the power of the fifty,  probably not a noticeable difference. I guess the machinist would just bore the cylinder. 
Title: Re: SLOW TAKE OFF
Post by: SUPER 9 MANN on May 16, 2015, 01:00:26 PM
That would be a 70cckit, the most popular.  I've put one on mine.  Not too hard.
was that just a carb swap
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 16, 2015, 01:05:31 PM
was that just a carb swap
We had come to the conclusion that there is a just slightly larger piston  that you can get and bore the cylinder to match it. 
The kit I was speaking of was a cylinder kit that comes with piston,  rings,  cylinder,  head, etc,  that makes the scoot 70cc. There are a few out there,  mine is cast iron,  there's aluminum ones as well. 
Title: Re: SLOW TAKE OFF
Post by: Triesandluth on May 16, 2015, 01:06:12 PM
MY NINE all of sudden is boggingdown off line and not revving up to gear . revs hanging in 5000-6000 range. I thought it was cvt issue so swapped belt clutch and bell . it did improve 10% but still not good. now it picks up but very extended and long. I am thinking of checking autobystander would this be the logicial next step? bike was ripping a few days ago. gotta fix today daily rider. stock except for aftermarket pipe and upjet to 95
Any luck,  mroc?