[So how do you really feel about the Kymco Mongoose 90's ???] - ATV Riders Forums - Honda, Yamaha, Suzuki, Kawasaki, Polaris, CanAm, Arctic Cat, Kymco ATVs

Pages:1

So how do you really feel about the Kymco Mongoose 90's ???
(Click here to view the original thread with full colors/images)

Posted by: tri5ron

Lay it on me,....

the good,
the bad,
and the ugly,
what do you think about these quads ???

I want to hear it all.

Thanks, Ron

Posted by: Hutchracer

We run a Kymco 50 that has we modded into a 70 and it has served us very well with no major problems. I think what you need to do is search out those that belive in these quads and gain knowledge from them. Performance parts are a little hard to come by if you look and ask the right people for info you will find them.

Posted by: THARNESS

Kymco builds a great quad. We had one that was ridden hard then passed down to little brother. The 90 will only run about 12mph out of the box. You will have to change a part in the front clutch that will allow the belt to travel fully. I guess thats Kymco's way of making the CPSC happy. The part is only about 20 bucks and once installed the quad will run about 30 mph.

Posted by: Logan #34's Dad

The UGLY - For Racing? - Been there, done that - It sucks! I bought the '08 National Champion quad (Winning engine in a better chasis). It was great for '08 but with the introduction of the 2 fast and Big Bore kits the 4stroke upgrade to a 125cc is obsolete. It cost my son a good overall finish in the 90 Jr. Production class this year.
The GOOD - If Kymco would produce a 90cc 2 Stroke in the chasis with the dual a-arm set up that was on mine (see mini sales section now - quadnana) it would be great. The chasis is very strong.
If they were smart they would introduce it with the piaggio based motor and put the others out of business. JMO
You asked!

For a yard quad? It would be great.

Posted by: wrhracing

Kymco in the Piaggio would be a interesting example of using what cases are most available, as one cvt/atv manufacture is already looking at doing just that.

Posted by: Hutchracer

As far as these machines sucking for racing? My daughter finished 2nd in points for flat track racing as a 50 in a 70cc class. I am not trying to be rude or anything but I can't help but wonder if the expectations were a bit high since it was a winning bike. The rider and the tuner make a huge difference as well as the whole package. We are now running a 70 kit on ours and it is as fast as the DRRs that we run with. By the way was that Jesse Skvarics old bike?

Posted by: Logan #34's Dad

Hutchracer, Yeah, this was Jessie's Engine with upgrades (pvl and custom pipe) and completely refreshed by his dad and other guru's. They absolutley know what they are doing. It just is not competitive anymore as I stated. I wish I could have found if Kymco made a 2 stroke Kymco quad so I could have upgraded to a 90 2 stroke because the Fisher Chasis is a good one minus the 300ex rear shock.
Is your 50 a 4 stroke? I'm guessing they did make a 2stoke at one time but I was unable to confirm it. I did not wanna get protested w/o having the facts.
As far as the rider and tuner - SHUT UP!

Posted by: Hutchracer

Like I said not trying to be rude or anything but looks like you took like that. We are running a 2 stroke and do just fine. I guess everyone has different opinions on these things. As far as the rider and tuner goes I asked that not trying to call you out or anything. We have seen killer bikes bought by racers that are not quite to the same level not perform as well then the bike was blamed as the reason for the lack of results. Lighten up man I didn't say you and your kid suck.

Posted by: tri5ron

quote:
Originally posted by THARNESS
The 90 will only run about 12mph out of the box. You will have to change a part in the front clutch that will allow the belt to travel fully.

does any one have any pics of this?
what part is it?
maybe a "how to"?

Also, With me being new to these quads, and new to CVT's,
I realize that I may be asking some dumb questions, But,
is there a way to adjust the clutch/belt so that it will hook up a little sooner?

Posted by: raptorobbie

tri5ron, to answer your question - yes you can tune the cvt to hook-up sooner. The real question is why do you want to do that??

With these cvt's you want the engine to reach an rpm at which its making some good power b4 engaging the clutch - otherwise very sluggish starts & no power to climb, etc.

There are some good - fairly easy to understand articles on how the cvt works and the pieces parts that make them adjustable. I would start off by reading those articles a few times & then ask questions based on what type of riding you're looking to do. Just my .02 but it helped me alot - good luck!

Posted by: airmobile101

quote:
Originally posted by tri5ron
does any one have any pics of this?
what part is it?
maybe a "how to"?

Also, With me being new to these quads, and new to CVT's,
I realize that I may be asking some dumb questions, But,
is there a way to adjust the clutch/belt so that it will hook up a little sooner?

Do you want it to hook up sooner with a kick or do you want it to flat out be fast off the line???? If your just wanting the clutch to engage sooner than stock, then just change out the three torque springs.

Posted by: tri5ron

quote:
Originally posted by raptorobbie
tri5ron, to answer your question - yes you can tune the cvt to hook-up sooner. The real question is why do you want to do that??

With these cvt's you want the engine to reach an rpm at which its making some good power b4 engaging the clutch - otherwise very sluggish starts & no power to climb, etc.

There are some good - fairly easy to understand articles on how the cvt works and the pieces parts that make them adjustable. I would start off by reading those articles a few times & then ask questions based on what type of riding you're looking to do. Just my .02 but it helped me alot - good luck!

the reason that I want it to hook up a little sooner, is because I want to have it hooked up at a much lower speed/rpm than most people would like. This is my son's first real quad, and he has VERY little seat time. I want to get the quad to run as slow as possible for him to learn on, and I dont want to be burning up the belt in the process.
10-12 mph will suit him just fine for a while.
it just seems to need to be running faster than that before it stops slipping.
he will not be doing any hill climbing, or off the line launches for a long time.
I will be using the throttle limiter to near maximum setting.

hope this clearly explains why I want it to hook up sooner.
Top speed/maximum power is not the priority here.

Posted by: tri5ron

quote:
Originally posted by airmobile101
Do you want it to hook up sooner with a kick or do you want it to flat out be fast off the line???? If your just wanting the clutch to engage sooner than stock, then just change out the three torque springs.

any suggestions as to what they should be changed to ?
or
any place that you can suggest to go look up the available springs?
Thanks,
Ron

Posted by: kfx450

sounds like you need to contact kymco and get the restrictor they come with from the factory. if your belt is slipping you need a new torque spring or belt. these engines are not putting out very much power stock so they shouldn't be slipping the belt. we started with a litle 4stroke to learn on as they have alot of torque for running slow as a beginner. the xtreme 50 had an adjuster on the cdi and you could turn down the rpms to almost nothing.

Posted by: THARNESS

It sounds like you have not yet purchased the quad or mabye just got it and don't have any time on it yet. I think you will find that the clutch stall speed will be just about perfect in the stock form. If you make it engage sooner it may not pull very well at all.

I think you will be amazed at how quickly your little rider will learn to ride.

If you start messing with the clutch you are going to spend alot of money with a good chance of it not working like you would hope. Then your kids skills will quickly improve and you will have to put it all back anyway.

With the factory speed limiter in the front clutch and the throttle stop you will be able to keep him very safe. His bicycle will be faster than his quad.

Posted by: raptorobbie

Ron, go for it - tear into the cvt a little - you're not gonna hurt that quad!

To engage sooner or at a lower rpm, change the roller weights in the front variator to a heavier weight, change large torque spring in rear clutch to a 1,000 and change the 3 small clutch springs to one setting softer.

Of course you'll need to know where you're at right now in order to make these changes, and like I said b4 read up on the CVT so you know why you're doing what you're doing! It pretty easy to do and should cost less than 70 bucks to do - have fun and experiment!

rob

Posted by: tri5ron

quote:
Originally posted by raptorobbie
Ron, go for it - tear into the cvt a little - you're not gonna hurt that quad!

To engage sooner or at a lower rpm, change the roller weights in the front variator to a heavier weight, change large torque spring in rear clutch to a 1,000 and change the 3 small clutch springs to one setting softer.

Of course you'll need to know where you're at right now in order to make these changes, and like I said b4 read up on the CVT so you know why you're doing what you're doing! It pretty easy to do and should cost less than 70 bucks to do - have fun and experiment!

rob

Thanks for the advise and the vote of confidence.
I called Malcolm Smith Motorsports in Riverside, (the closest dealer to me), and talked to one of the service tech's. He told me that I would need to put in LIGHTER rollers. I said are you sure they should'nt be HEAVIER rollers? and he replied that lighter rollers would make it engage sooner.

so now, (without opening it up yet), I'm a little confused.
I am under the impression that these rollers are working by being mounted to some sort of spinning assembly, and therefore using a centrifical action to determin at what rpm they engage.
If my assumption is correct, then it would make sence that HEAVIER weights would engage sooner.

But then I started thinking a little past the whole clutch/belt adjustment idea.
I started wondering if it might make more sence to just drop the front sprocket down 1 or 2 teeth, and basically accomplish the same thing.
I'm guessing that this will result in the belt engaging at the samr current rpm's, (hence, in the preferred power range), yet it will give a little more bottom end torque to the wheels, while at the same time slowing the quad down some once the belt is fully engaged.
(keep in mind that I am currently using the throttle limiter screw at near max. setting), meaning that I am not giving him very much throttle range at all.

so what do you guys think about changing the front sprocket idea, for my intended purpose? and are other sprocket sizes available to fit these machines?

I think that IF this would work,...
it might be a cheaper way to accomplish my intended results.

Posted by: raptorobbie

No, your thinking is correct - you need less rpm w/ heavier roller weights to start pushing that belt up the variator. If that's not correct, I'll have to tear up my engineering degree again!! The mechanic may have been thinking or talking about the rear springs being lighter.

As for the sprocket change-out...that sprocket, no matter what size it is, doesnt move until the cvt makes it move - therefore I would still change those roller weights and leave the sprocket alone.

I did the same thing w/ my sons DRR 90 - I went to heavier weights to reduce the rpms b4 engagement so the bike wasnt screaming so loud around the home track. Worked great at home but not so good when we went for some real riding on the trails and other tracks (which was expected).

Posted by: tri5ron

quote:
Originally posted by raptorobbie
No, your thinking is correct - you need less rpm w/ heavier roller weights to start pushing that belt up the variator. If that's not correct, I'll have to tear up my engineering degree again!! The mechanic may have been thinking or talking about the rear springs being lighter.

As for the sprocket change-out...that sprocket, no matter what size it is, doesnt move until the cvt makes it move - therefore I would still change those roller weights and leave the sprocket alone.

I did the same thing w/ my sons DRR 90 - I went to heavier weights to reduce the rpms b4 engagement so the bike wasnt screaming so loud around the home track. Worked great at home but not so good when we went for some real riding on the trails and other tracks (which was expected).

Thanks Raptorobbie for the advise, and taking the time to read and reply. I really do appreciate it.

I was thinking the same thing about what the mech. said, and assumed that he was probably just thinking the springs, i.e. lighter springs.

(I've got 26 years in aircraft assembly, modifications, and repairs myself, with a little engineering experience too, so for a moment there, I was starting to wonder if this whole variable drive thing was something other than what I had mentally pictured. LOL!).

OK, so let me bounce the sprocket idea at you again, and see what you think...

As it is currently set, I don't necessarily mind that the rpm's need to be as high as they are, prior to full engagement of the drive belt.
Actually that makes sure we are in a good power band for the engine. Right ?

My main issue with it was/is, that I don't WANT to give it more throttle range, with the limiter,....
to allow for the full belt engagement,.....
DUE TO,...
it results in the quad being able to ultimately gain more speed than I am comfortable with, once the belt HAS engaged.

(all of this, is still WELL below 1/2 stroke on the thumb throttle lever.)
Basically, I'm looking for a brisk walking pace.

I do realize that the primary sprocket/drive chain, is not going to start moving, until AFTER the variator has allowed for engagement of the belt.
but I'm starting to think that by changing the gearing of the drive chain, (to lower gearing),
I may accomplish my intended objective,as well as doing it as cheaply as possible.

That objective being,...
that we acheive full belt engagement, yet have a slower forward speed AT full belt engagement.

Since it is not really the RPM's themselves that bother me. it's just that, AT those current RPM's, (for full engagement),the quad goes a bit faster than my son is ready to handle.

I'm not sure if you saw my post on, or about my son,
but if you did'nt then maybe this will help explain WHY I am trying to do these things...

My son is 10 years old, and has Down Syndrome. (and he wants to ride REALLY BAD ! )
He is actually a pretty sharp little dude, BUT, He DOES learn things slower than typical kids, (we, as special needs parents, use the term "typical kids", as opposed to, "normal kids").

Since he DOES learn at a slower pace, it is all the more important that he feel a sence of accomplishment EARLIER than typical kids, so that he will maintain a intrest in something, rather than getting frustrated, and therefore stop trying.

This gets combined with the fact that he will also have a tendency to get "tunnel visioned", when trying to learn new things. That means that when he gets the quad moving, he is more focused on GOING, and less focused on avoiding obstacles, or stopping.
These things will come with time, and practice, but it's best to go at it one thing at a time.

We go camping at a large Dry Lakebed, that is flat, smooth, and easy to keep him contained in a prescribed area. this will be the best and safest surface and environment to get him started.
Hopefully he will gain some confidence quickly, and therefore be able to comprehend the importance of watching and avoiding obstacles, as well as STOPPING BEFORE HE RUNS INTO THE SIDE OF THE CAMPER !!! LOL!
(trust me,... he's not getting anywhere NEAR the camper for awhile, LOL!)

I have also been looking into some aftermarket, (ebay), Remote Controlled Kill Switches, that I am hoping to get some experienced folks, to comment on.
(I had asked about them in another thread, but so far no replies).
if they can be applied to his quad, and give ME more controll over the situation, then it would also allow me to let him go a little farther or longer without having to shut him down.

keep in mind that the more time he gets, while feeling that he is being sucessfull,.... The faster he will learn everything he needs to learn, and be able to ride more safely.

He WILL get there,
it's just going to take some time, and alot of supervision at first.

So hopefully this explains why I am faced with a few more hurdles than the average parent, trying to teach the average, "typical", kid.

I'm also hopeful that he will quickly catch on to all the necessary skills, and can then give him full throttle range, and let him go "Hog-Wild" ha-ha.

so with ALL said,...
What say you ???,...
on the primary chain sprocket idea ? as opposed to the modifing the roller weights, spring tensions idea ?
(and also the remote kill switch idea).

THANKS again, for taking your time to consider these issues.
Ron

Posted by: THARNESS

That helps explain what your trying to achieve, which if I read correctly, is a lower top speed.

A smaller front sprocket will help with that. Back when we ran Kymcos, the front sprockets were held on by two small bolts and a clip. If that is still the case, they are kinda hard to find. I had Rebel Gear make me some. If its the type that is held on by a large nut, you should be able to find them at most mini atv performance shops, such as Hetrick Racing.

You can also use a larger rear sprocket which you can also get at Rebel or any mini quad shop. With a larger rear you will also have to get a longer chain.

A shorter set of rear tires like come on the Kymco 50 will also do the trick. I think I may have a pair of stock 50 tires and wheels that I would give you if you would like to use them.

Any one of these things or a combo of them all will help slow down your quad.

I had a remote kill switch on my youngest sons quad when he was little. It worked great but the range wasn't that good. It worked best if I rode behind him on my quad and kept him in range, but then he would keep looking back at me and veer into something.

Good Luck

Posted by: tri5ron

quote:
Originally posted by THARNESS
That helps explain what your trying to achieve, which if I read correctly, is a lower top speed.

A smaller front sprocket will help with that. Back when we ran Kymcos, the front sprockets were held on by two small bolts and a clip. If that is still the case, they are kinda hard to find. I had Rebel Gear make me some. If its the type that is held on by a large nut, you should be able to find them at most mini atv performance shops, such as Hetrick Racing.

You can also use a larger rear sprocket which you can also get at Rebel or any mini quad shop. With a larger rear you will also have to get a longer chain.

A shorter set of rear tires like come on the Kymco 50 will also do the trick. I think I may have a pair of stock 50 tires and wheels that I would give you if you would like to use them.

Any one of these things or a combo of them all will help slow down your quad.

I had a remote kill switch on my youngest sons quad when he was little. It worked great but the range wasn't that good. It worked best if I rode behind him on my quad and kept him in range, but then he would keep looking back at me and veer into something.

Good Luck

Tom, Thanks for the reply
Yes I am trying to obtain a lower top speed, but more accurately, a lower speed upon full drive belt engagement.
(I'm not giving him the full range of the thumb throttle yet, so therefore it's not getting the top speed reduced that I'm concerned with right now).

and yes you are correct that it is the type of counter sprocket that is held in place with the 2 small bolts and a clip.
Did you happen to have a 15T made that you are interested in getting rid of?

I have spent most of the day going to various on and off brand dealerships and parts houses, and have confirmed what you already know,.... they just don't make the darn things in a 15T.
I even went to a commercial chain/gear/bearings and drives supplier, ... Nada!
(although I did determine the pitch to be a size #40)

The part that is being the problem is the I.D. size, and splines size. (i'm sure your already aware of that, seeing as how you went and had some made)

I have not yet removed the rear sprocket to determine if it might be more fesible to find / alter / make a larger rear sprocket.

Also, It's very kind of you to offer me the smaller wheels and tires, Thank you.
I'd love to try that, but I'm guessing it would cost more to ship them from Alabama to California than it would be worth. I may have to see if I can find some tires that are 2" shorter, and fit the stock rims, or something like that.

I would have bet dollars to donuts, that it would be a simple thing to find and swap the counter sprocket. well, just not my luck I guess.
Now, I'm begining to think I'm back to square one, and changing the roller weights to heavier may be my only option.
DANG IT !!!
Maybe I should have just bought another TRX90, stuck it in 2nd gear, removed the shifter, and adjusted the throttle limiter screw.

I'm feeling more frustrated than a 2 peckerd hound dog chained to a cat box.

Posted by: THARNESS

Back then we were Dirt Track racing so all of the front sprockets we had made were larger for more top speed.

The rear sprockets are easy. It is the same ones that will fit a DRR,Polaris,Apex ect. If you will google "Rebel Gear" and tell them what you need they will have it out to you in a couple of days. They have always been very helpful to me.

I'm really not sure if the roller weight change will give you the results you desire.

The weights effect the rpm required for the belt to begin to travel or in essence for the quad to "shift gears". Normally a heavier roller will make it "shift to high gear " sooner,thus it will not accellerate as quickly, or pull hills as good, but if you are riding in a dry lake bed like you mentioned the engine will eventually catch up to the clutch and top speed will be the same as before if not a little more because the belt may travel a little further than stock.
Lighter rollers keep in "low gear" longer before the belt travels and it will take more rpm's to make the belt travel. It will most likely be more responsive on the low end and will pull hills better. You will most likely lose some top speed with lighter rollers because the belt will not travel as far.

Don't get frustrated, most of us on here have been there, and will be glad to help you out. I will PM you my phone #, call me if I can help.

Posted by: THARNESS

Also, If your quad still has the factory spacer in the front cluth, it is limiting travel anyway so I doubt if lighter or heavier rollers will affect top speed at all. Good luck.

Posted by: quadnana7

Output shaft on our Kymco accepts same front sprocket as Kasea setup Rebel should have them in stock

Posted by: jetta75

I haven't bought one of those stand alone remotes, but did have one on his first quad a couple years ago. It was good to shut him down if he got too close to cars/house. At that speed it wouldn't be hard to run close enough for remote to work if you can't ride while practicing.

Posted by: tri5ron

Thanks for the replies and the PM's guys.
I will be calling you with some questions.

right now, I feel like I've been run over by a truck.
Kids came home with the flu, now the wife and I both have it.
Everyone in the house is sick and feeling crappy.

Worked a 14hr day today, and can hardly stand up.
wife just brought me some dinner, then I'm heading for the sack.
gotta get up at 4am, to go make a concrete delivery 40 miles away, through L.A. traffic.

I'll get back to you guys when I get over this fever and body aches.
My freaking toenails and eyelashes even hurt right now.

heading for bed now.

Posted by: airmobile101

quote:
Originally posted by quadnana7
Output shaft on our Kymco accepts same front sprocket as Kasea setup Rebel should have them in stock

JT Sprockets makes them also.
Heres the part #'s

JTF259.15 15 TOOTH
JTF259.16 16 TOOTH
JTF259.17 17 TOOTH

Posted by: tri5ron

You guys have been absolutely Fantastic with all of the advise, direction, and assistance.

I can't express how VERY COOL that is, and how it will ultimately benefit my little buddy, as well as our family.
I learned along time ago,
that sometimes you never realize how your simplest actions,
can have huge positive effects on or for others.

I especially want to thank the couple of you who took the time to speak with me on the phone today, and we discussed the options for acheiving my intended objectives.
I learned alot from the both of you today, and quickly realized 2 things...

1- I was completly "brain-farting" on the functional operation of the CVT clutching actions,...(I didn't initially realize the variator, and the clutch, are two seperate functions,... DUH !)

2- that I should be able to get this little quad tuned in, perfect for my son Nickolas., with minimal changes, costs, or effort. YEA !!!

I have also realized that although you guys are collectively, a pretty aggresive competitive group,....
you all are very quick to come together and assist a newbie like me, and help make a good thing happen for the kids.
As well as speak rather kindly of each other, (even though I promised that I wouldn't reveal that to the general public,... ha-ha )

That's WAaayyy cool, and I can honestly say that anyone of you are welcome in my camp anytime. I'll have a BBQ, and a cold drink waiting for you, and a pile of s'mores waiting for the kids.

In case you hadn't seen it over in the open forum, I thought you might enjoy a pic of Nickolas when we presented him with his "New" quad, a couple weeks ago.
He pretty much went bananas, and took all of 5 seconds to start asking for the key, LOL!

http://i111.photobucket.com/albums/n148/tri5ron/04%20Kymco%20Mongoose%2090/IMG_0391.jpg

http://i111.photobucket.com/albums/n148/tri5ron/04%20Kymco%20Mongoose%2090/IMG_0389.jpg

Looking forward to get him out on it and bringing fear to the hearts of every jack rabbit in the desert !

Will keep you posted on the end results for clutch springs / gearing changes.

Ride hard, Ride safe, and keep the rubber side down !!!
Ron

Posted by: raptorobbie

I like the 2nd shot w/ the "pride just ooozzzing from him"!!!!

that's great - this sport is an excellent learning experience and challenge for all of our kids - we just need to keep it safe and fun for them! We had a great ride this weekend in northeast Ohio w/ temps in the upper 60s - very abnormal for us!!

keep the updates on Nickolas coming...