Problems with Roketa MC-54-250B By serenity09 (Read 11,134 times)

[serenity09]

Okay, soooo, I purchased a Roketa 250cc Scooter about two months ago. It now has a little over 2000 miles on it. When I initially got it, I heard some slight noise, as if a belt was rubbing against something ever so slightly, and as time went on, it got progressively worse. UNTIL yesterday, when against my better judgment, I decided to ride it a bit, when it just suddenly decided to I assume, snap? Because even though it starts, it won't go anywhere. I will say, it definitely SOUNDS better without what I assume was the belt on it -- my brother in law says that the belt might have just been on there too tight, which was probably causing all the other issues I've been having with it. But I digress, so yah... I haven't really found anything in the parts catalog saying it even HAS a belt though.

Also, other issues I'm having: when at a stop, I have to hold the throttle around at LEAST 3000+ rpm's just so it won't die on me... you can imagine the kind of pull it has when applying the brakes at 3000 rpm's. Horrible idling. And it's been having problems with accelerating. The gas gauge has also stopped working.

I just wanna get it running again so I can sell it and upgrade! PLEASE HELP ME rawr. What do?

[speedracer]

You most certainly have a belt under the CVT cover. Do you know what engine you have in it? Linahi or Honda clone as they use different belts. Also there is something else wrong in there as your belt should not even be close to wearing out with 2000 miles on it.

More then likely you might need a valve job as it should idle fine at 1800-2000 RPMs.

[serenity09]

Thank you for the belt confirmation, now I know I'm not wasting my time with trying to get to it, lol. >.>

Just based on some random browsing on this site, I'm pretty certain it's a Honda clone. Next question: where can I get my hands on a belt for this model?

Also, I'm having difficulty locating the idle screw, not sure where to find it; trying to do this on my own, kinda ignorant to working on anything mechanical, so if I could get maybe a picture of what I'm looking for, that'd be awesome. I've tried searching all over Google, but no such luck.

Is a valve adjustment hard to do? Erm... what exactly IS a valve and how do I adjust them? Heh. = /

Annnd where is the air filter? -_-,

[bobf]

Most likely it is a Honda clone. If the VIN starts with LJ4, then it is a Honda. Another way to see is if it is a vertical engine it is a Honda, if it is a horizontal engine it is a Linhai.

For the carburetor idle adjustment screw. Lift the seat. Locate a rectangular panel with two screws. Remove the screws and take off the panel. You should be able to see the carburetor and one of the screws will have a spring under it. This is to the rear of the panel opening. That is the screw you will turn to raise or lower the idle speed. Turn only very small amounts, like a 1/8th of a turn and wait a few seconds for the engine to steady to the new mix. Watch your tach and readjust up or down as needed until the tach shows approximately 1800 rpm. I forget which way is up or down so check your tach and see which way the rpm's are going as you make the 1/8th turns.

I will let someone else tell you about valve adjustments as I have not done that on my scoot yet.

Best solution for the gas gage is to fill the tank and keep track of miles driven. At some determined miles, get more gas. Pick 100 miles or 150 miles, or what ever you feel comfortable with.
.

[Cruiser]

Welcome to Scooter Doc, serenity09.
If it's a Honda clone, then the belt should be a 918 x 22.5 x 30.

Also, holding the brake while revving the engine at 3000 rpm is what most likely what killed your belt. This overheats the belt along with the clutch.

Does the scoot idle OK while warming up (first one or two minutes)? You may have a blocked idle mixture circuit in the carb.

Here's a picture of the air filter on the Honda clone. It's located just above the CVT cover under a black plastic cover.



Here's a video on adjusting the valves on this engine. The valve adjusters are located at the top of the engine up above the CVT. There is a small plastic door with one screw in the bottom of the seat bucket which allows access to the valve adjusters.

[speedracer]

Here is one link to finding the belt you need. absolutelyscooterparts.net/catalog/drive-belt-p-124.html

I when changing the belt take off the bell cover on the clutch and take a good look at the clutch as Cruiser said it could be worn down. More then likely you will need a impact wrench as the variator fan and clutch nuts have to be removed to replace the belt.

[serenity09]

Air filter status: clean. Valve adjusters: discovered.

Thanks guys, I appreciate the help.

Upon further investigation, I've discovered that it is the Linhai model, not the Honda clone. SO what kind of belt and where can I get one? Mines an automatic btw, I didn't know they even made manual scooters, but I keep seeing mention of a clutch; dunno if that makes any difference, just thought I'd throw it out there.

Also, playing around in the guts, I came across this brass cover plate that had a spring under it, and a rubber circular object with a small pin needle sticking out the end, which out of foolish curiosity, I took out, now it's not starting!! Gah. I'm afraid I may have pulled a 'typical female' move and messed with something that shouldn't have been messed with, lol. I'm hoping not! Any idea what that was? >.<

[Cruiser]

The brass cover with the spring under it is the carburetor diaphragm. You're right - you shouldn't have messed with it. Here's a tutorial on how to adjust the needle jet. In this case you are not interested in adjusting anything, but it does show how to put the diaphragm back together.

scooterdoc.proboards.com/index.cgi?board=intake&action=display&thread=801

Modern scoots are all automatic which means they use a CVT or continuously variable transmission. These transmissions use a variator on the motor and a clutch on the rear wheel which is connected to a gear box. The clutch is really an automatic clutch which is controlled by the speed of the engine. Also known as a centrifugal clutch.

[speedracer]

Ok, now you need a different size belt. 856 23 30. There are many vendors here who sell that belt. You may wish to try ebay as well. To locate the idle screw on the linahi engine. Lift the seat, remove the two screws holding on a plastic cover. You are now looking down on the top of the carb. If you are on the kick stand side the screw is on the opposite side with a spring under it. To make it idle faster turn the screw clockwise. As stated before 1/8 turn at a time and let the engine adjust to getting more gas. Watch the tack and when it's between 1800 and 2000 you should have a smooth running engine. Mine runs best at 2000.

[bobf]

Jun 30, 2011 10:09:48 GMT -6 serenity09 said:

Air filter status: clean. Valve adjusters: discovered.

Thanks guys, I appreciate the help.

Upon further investigation, I've discovered that it is the Linhai model, not the Honda clone. SO what kind of belt and where can I get one? Mines an automatic btw, I didn't know they even made manual scooters, but I keep seeing mention of a clutch; dunno if that makes any difference, just thought I'd throw it out there.

Also, playing around in the guts, I came across this brass cover plate that had a spring under it, and a rubber circular object with a small pin needle sticking out the end, which out of foolish curiosity, I took out, now it's not starting!! Gah. I'm afraid I may have pulled a 'typical female' move and messed with something that shouldn't have been messed with, lol. I'm hoping not! Any idea what that was? >.<

Since you have decided that you have a Linhai engine I was wondering if you could tell me if the first numbers of your VIN are 5RY. If so your model is likely MC-54B-250

How am I doing so far? I have been trying for a long time to understand the names applied and what you get. Getting close and will soon post what I have been finding.

I hope I can find something informational to post, but maybe not.
.

[speedracer]

Jun 30, 2011 10:09:48 GMT -6 serenity09 said:

Air filter status: clean. Valve adjusters: discovered.

Thanks guys, I appreciate the help.

Upon further investigation, I've discovered that it is the Linhai model, not the Honda clone. SO what kind of belt and where can I get one? Mines an automatic btw, I didn't know they even made manual scooters, but I keep seeing mention of a clutch; dunno if that makes any difference, just thought I'd throw it out there.

Also, playing around in the guts, I came across this brass cover plate that had a spring under it, and a rubber circular object with a small pin needle sticking out the end, which out of foolish curiosity, I took out, now it's not starting!! Gah. I'm afraid I may have pulled a 'typical female' move and messed with something that shouldn't have been messed with, lol. I'm hoping not! Any idea what that was? >.<

You removed the needle valve and diaphragm . It is never going to start until you replace it. Make sure the diaphragm is clean and put in the same way as removed.

[bhinch]

Try Ebay for the belt...856-23...the number should be on the belt if there is anything left of it......a vendor has the belt for $9.00 plus freight...the belt sells for 50 to 60 bucks else where...I bought two... just search the belt number...856-23.....enjoy your scoot...