mc-54-250b loss of power By deanc (Read 2,190 times)

[deanc]

the scoot seems to have less power since replacement of clutch. I have, replaced fuel filter, pspark plug, all fluids. adjusted valves, cleaned and put back together variator, new belt, new clutch. I dont know if the tank of bad gas that made the scoot idle rough, (i drained the tank and replaced it) or the new clutch has caused the seeming lack of power. the clutch is all new, it is a little stiffer than the old sqeaking one. belt same size, used graphite in the variator after cleaning it out, rollers are fine. initially i put in dr. pulley sliders and alittle grease but that didnt seem to work as i thought. so i went back to the rollers and no grease. so...the only differances are the bad gas and new clutch..that coincide with the loss of power.

[JR]

First of all Welcome to the forum! Ok now lets take it one step at a time, you've replaced a lot of things but this is my concern now you've cleaned out the variator and used graphite even then it will gum up and can cause the rollers to stick. Got a good friend who said he thought the graphite would do well and I told him I thought it was a mistake and just a short time later he got his plate out for his serving of crow! LOL But he's a great guy and if he reads this he'll for sure tell you about eating crow. Now enough on other lessons learned! LOL

Sliders point blank NO GREASE! They are self-lubricating and grease will just stop them from functioning correctly. So lets get familiar with your area and riding, do you ride basicaly on flat ground or the hills like myself (Arkieland) or a combination of both? I'm sure if you have the 250B then it's a linhai so here is a slider upgrade tutorial with pictures of the 244cc and the 257cc clone variators and what they look like;

thescooterprofessor.proboards.com/index.cgi?board=250ccvt&action=display&thread=216

It shows a picture of the sliders properly installed and what to expect on each variator. One does want to grease slightly the centershaft (boss) and the little hard composite "U" slides on the ramp plate, I use a very slick lithium grease and that's it no grease or graphite on the sliders or in the tracks. Make sure each roller/slider track in the variator is smooth and has no restrictions to keep them from moving freely or this can cause trouble.

Now what size sliders did you get? Most 250B's with the linhai come with 14g rollers and where I ride in trhe hills I use 12g sliders, keeps my top end but gives me more low end for the hills, if you ride on flat ground 13g sliders work well gives you a little more take off but keeps great top end.

Now to the clutch and a question, what about the belt? Same OEM belt? How many miles on the scooter? Lastly was you careful and didn't get any grease on the belt? A worn belt that is not gripping properly will lose top end, what size is your belt, the 856-23 or the 871-23?

If you replaced the clutch apples for apples it will not contribute to your loss of power unless you got a lemon and I doubt that.

Now bad gas a different story, and when you say bad in what way, had water in it or impurities or both? Did you replace the filter again after the bad gas? Clean the carb? It's possible that you have a partially clogged main jet? How about cleaning the air filter?

Like with a lot of things this process is a elimination one and we know you have worked on the variator, replaced the clutch and have had a hit of bad gas, if she was running fine before that then here's where we start, myself I would pull the carb and give it a good cleaning with carb cleaner, blow it out good and throughly check each tiny hole in the main jet, replace the fuel filter and put some fresh gas in it and give it a try.

I would also re-work the variator and re-consider the sliders, you'll like them better. Keep us informed and again welcome to the forum!

JR

[deanc]

ok, lets start with roads. they are flat curvy and hilly. i replaced the belt with a new one but it left black crumbly dust, and the old gates was fine. 856 by the way. everything was fine, till i changed the clutch and variator, and bougth the gas that made it run rough. I agree the clutch and belt should be fine, no slipping there. I did turn the idle down after the repair because it was idling way too high and the wheel was always rolling.
I have not touched the carb or fuel filter after the poor gas. if use gas from the same place in my jeep it also runs really rough.
I dont mind trying the sliders again, it just seemed that it lost top speed and made a funny noise. maybe too much grease. so where did you say i should start?

[deanc]

also in addition....i put on the new belt before the clutch came a week later. the belt left a black line on the pulley and variator pulley, which i took off with steel wool. also felt/sounded like it was just not shifting. so i went back to the old belt and rollers.

[JR]

Ok so the new belt left a black line and stuff on the variator? If so then either it got grease on it and burned it off thus leaving the black line or the belt is poor. Did you buy the quality gates powerlink belt?


Again I would clean that carb out and get some good quality gas and a touch of seafoam to clean it all up good, also change the filter, if you haven't cleaned the air filter lately do that also.

Yes the grease with the sldiers will cause it to act funny and what weight did you get? As I said 12g really runs sweet in the hills and if all else is right then she'll lose no top end.

Keep us posted and we're here to help.

JR

[deanc]

13g sliders. and the belt i put back on was a gates belt the one i got that left the mark was a chinese $20 belt. I thought the gates belt was squeaking but it looks fine, it was the clutch that was bad. new clutch old belt= no squeak. i do have some seafoam, how much would you say? I rained well over 2 gallons outta the tank and that was after i put 100 miles on the tank of gas. so change filter clean carb. put sliders back in w/o any grease or graphite. is that my plan?

[JR]

Yep and if you're really in some good hills you may want to consider 12g on the sliders? Or you could buy a set of 11g's and mix and match say 4 of the 11's and 4 of the 13's = 12g and if you thought you want a little more pull up those hills put all 11's in all depends on what you're looking for?

So clean carb, new filter, clean gas, clean up variator and put back sliders with NO grease and give her a spin. It doesn't take much seafoam so with a dry tank about 3 ounces directions say 1 once per gallon.

JR

[deanc]

thanks i'll get to work. and let you know how it goes.

[deanc]

ok power back but vibration on take off. geez. whats next.

[deanc]

does a new clutch need sanding? in the bell and pads?

[JR]

Not unless that belt is gummed up on the pulley faces and NO sandpaper unless its 120 or litghter grit and even then I would be very careful, if that face is not silky smooth because of the cheap belt the good belt may be having trouble. If you find matter on it I would try carb cleaner and steel wool very fine grade.

Now on the pads a new clutch should have no issues with pad glazing but if they are glazed or even one of them is then the clutch is not gripping the bell like it should untill you reach a higher RPM and of course the only way to know is to remove the clutch bell and inspect, you can gently sand them and clean them with brake pad cleaner but again I just don't see a new clutch having this issue but it's worth looking at.

Another thing I've done when I had this problem is fgo to the dollar store and get you a can of this;



Yep roach powder, it's 99% boric acid and you can slightly coat the pads with this and the insdie of the clutch bell and after a spell it will make the clutch pads seat to a perfect fit to the bell works good on disc brake pads too, added benefit "roach free scooter" ;D

Also did you take the variator apart yet? if not the gease on the rollers may be causing a roller to stick thus causing it to vibrate?

JR

[deanc]

thanks, gonna take apart variator tomorrow. wife road it to work today after my adjustments last night and said she had no vibration and no power loss. maybe idle was set wrong causing clutch to engage at wrong time. gonna remove variator graphite and replace with dry sliders, this weekend.

[JR]

Great Dean and glad she's coming together and you know you're going to have to get anojhter one for you and the Mrs.! My wife and I both own the 250 with the linhai, her's is the 250a and mine the B we both ride together evry chance we get.

Killer still has some 07 new in the crate 250A's.

Again let me know how the sliders are doing and give it a good ride on those hills and if you don't mind me asking where is the hills? LOL

Also when you're asked if you don't mind please let everyone you know that we're here and glad to help.

JR

[bhinch]

Great info...thanks JR.....you the man.....I like the way you answer peoples questions....with thought about their knowledge....makes it easy to follow and understand....thanks again...

[deanc]

sure will this is great place for info....the hills I speak of are in middle tennessee, outside of Nashville.